SELECTION OF OPTIMAL INVESTMENT STRITEGIES FOR LOW VOLUME ROADS by MARK ARNOLD BECKER SB, Massachusetts Institute of Technology Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology June, 1972 Signature ofAuthor ................ •.•.....•••.... Department of Civil Engineering March 17,1972 Certified by...... ...... T... . Thesis Super isor Accepted by.. ........................... ........... Chairman, Departmental Committee on Graduate Students of the Department of Civil Engineering ABSTRACT SELECTION OF OPTIMAL INVESTMENT STRATEGIES FOR LOW VOLUIME ROADS by MARK ARNOLD BECKER Submitted to the Department of Civil Engineering on February 20, 1972, in partial fulfillment of the requirements for the degree of Master of Science. This thesis presents the Highway Cost Model, a set of twenty computer routines written-in FORTRAN IV which model the behavior of low volume road investments over time. The model was designed to be a tool with which planners in developing nations could locate those road projects which would provide optimal return on scarce and constrained resources. The HCM can consider uncertainty in traffic projections, labor versus capital intensive maintenance and changes in factor prices over time. Thesis Supervisor: Fred Moavenzadeh Title: Associate Professor Acknowledgments I would like to thank my wife, Deborah, for her advice, encouragement hard work and much, much more. I would also like to thank Thomas Parody for his work with the cost estimating routines and Louis Berger, Inc. who provided me with essential data out which this thesis could not have been written. Last, I would like to thank Fred Moavenzadeh for his support and advice. with- CONTENTS I. II. III. IV. V. VI. Title Page Abstract 2 Acknowledgment 3 Table of Contents 4 Chapter One: Introduction 11 1. Maximizing Value: Modes of Approach 12 2. Problems of Staged Construction 14 3. Economic Issues in Staging 14 4. Use of Staged Construction in Project and Systems Analysis 17 5. 18 Determining Optimal Staging Strategies Chapter Two: Review of Literature 1. Staging Techniques 20 20 Specific Highway 2. Staged Construction: Techniques 3. Staged Construction as Practiced in Developing Nations 24 4. Staged Construction: Pavement Design 29 5. Empirical Models 29 6. Mathematical Models for Staging 33. 7. Facets of the Problem: The Timing Issue 33 8.. The Design Issue 35 9. Budget Constraints 22 36 10. Staging Under Uncertainty 37 11. Summary 37 VII. VIII. IX. Chapter Three: Developing the HCM 39 1. The Basis: Cost Estimating Routines 39 2. Developing the HCMM 41 3. Selecting an Approach: The Alternatives 43 48 Chapter Four: The Computer Routines 1. The Staging Routines 48 2. Relationship to Cost Estimating Routines 63 3. 68 The Highway Cost Model Flowchart Chaoter Five: Exxreriments in Staged Con- 74 struction: Techniques and Results 1. The Experiments 74 2. The Scenarios 77 3. Expanding the Parameters 78 4. Elasticity of Demand 79 5. Growth Rate 83 6. Maintenance Policies 84 7. Discount Rates 91 8. Foreign Exchange 94 9. Length of the Analysis Horizon 96 10. Results of the Experiments: Rules The Pruning 100 11. Rules for Flat Terrain 102 12. Mountainous Terrain 102 13. Maintenance 104 14. Pruning Rules: Other Issues 105 Page 15. X. The Use of the Pruning Rules Chapter Six: Use of the HCM 1. Data Collection XIII. 107 Construction-Related Data 109 3. Maintenance-Related Data 111 4. Data Related to User Operating Costs 112 5. Development and Selection of Staging Alternatives 116 6. Timing 117 7. Upgradings 118 119 Search for the Optimal Road 121 10. Continuing the Iteration 127 11. Length of the Analysis Period 127 12. Effects of Uncertainty in Traffic Projections 130 13. Effects on Total Costs 14. Initial Traffic Levels 15. Effects on the Optimal Strategy 16. Road User Benefits 9. XII. 107 2. 8. Maintenance XI. 106 131 135 136 138 140 Chapter Seven: Conclusion Bibliography 144 Appendices 150 A. Recommendations for Further Work 151 B, Willingness to Pay 153 Page C. Argentina and Bolivia Data 158 D. The Earthwork Models 163 E. Listing of the Highway Cost Model 166 LIST OF FIGURES Number Title Page 1 Costs of Staged vs. Unstaged Construction 25 2 Flowchart for MAIN 50 3 Flowchart for STRAT 53 4 Flowchart for NETWRK 55 5 Flowchart for SAVDAT 62 6 Flowchart for CONSTR 64 7 Calling Sequences 67 8 Macro Flowchart for the HCM 69 9 The Staging Strategies 76 11 Argentina: Costs of Normal + High Elastic Traffic 82 Argentina: Costs of High + Normal Traffic Growth 12 Per kilometer operating costs vs. Maintenance 88 13 Maintenance Policy vs. Velocity 89 14 15 Maintenance Cost of Asphalt + Surface Treated Roads Advantages of Staged Construction 90 92 16 Effect of Interest Rates on Total Costs 93 17 Foreign Exchange Requirements--Low Traffic 97 18 Foreign Exchange Requirements--Normal Traffic 98 19 Foreign Exchange Requirements--High Traffic 99 20 Bolivia: Costs of Staged and UnStaged Roads 101 21 Map of Sapecho-Puerto Salinas Route 108 22 Bolivia Base Scenario Echo Print 114 23 Costs of the first Iteration 124 10 85 Title Number 24 Staging Strategies for the Second Iteration Page 125 25 Costs of the Second Iteration 126 26 Costs of the Third Iteration 128 27 Action of the Communication Model 141 28 Definition of Willingness to pay 154 29 Argentine Base Data 159 30 Bolivia Base Data 161 LIST OF TABLES Number Title Page 1 Traffic Conditions used with Bolivia Data 80 2 Traffic Conditions used with Argentina Data 81 3 Labor and Capital Intensive Maintenance Policies 86 4 Foreign Exchange Component of Costs 95 5 Base Traffic for Bolivia Case Study 122 6 Effects of Inaccurate Growth Rates 132 7 Vehicles in Year 20 for two demand elasticities 134 Chapter One Introduction The lack of adequate transportation in many developing countries has been cited by Haefele (48), Soberman (58), and Steiner (42), among others, as one of the factors slowing down the rate of industrialization and general economic development in those countries. Transportation brings raw materials to factories, workers to jobs, finished goods to market, food to urban areas, and health and educational services to the outlying population in much the same way that arteries move vital resources through the human body, thus making possible a complexity of function far beyond the capacity of any single isolated organ. It is clear that an underdeveloped country with rich natural resources and a populace eager for progress must have such a means of collating its own particular energies and materials if it is to fulfill its highest potential for industrialization. One reason for the inadequacy of transportation facilities in countries with scarce capital resources is the high cost of constructing roads, railroads, and similar basic components of the transport system. If these facilities could be constructed at lower costs per kilometer, then for any given investment more kilometers of road or rail could be constructed, and so a greater contribution could be made to the economic development of the country. 1. Maximizing Value: Modes of Approach One obvious method that could be used to extend the mileage made available per investment dollar would be the construction of lower quality, cheaper roads. policy by itself is shortsighted, since it However, this can lead to in- creased costs (gasoline consumption, vehicle deterioration, driver salaries) for the individual user, so that ultimately no real economy has been achieved. Another disadvantage of this form of construction is the maintenance expenditure required each year to keep the road in adequate condition. If many roads in an area require a high maintenance effort in order to keep the roadway passable, resources needed for other projects would be unduly tied up, and so new construction would necessarily be restricted. Since many developing countries have comparatively little capital equipment, this drawback can be regarded as a critical one. On the other side of the spectrum is the alternative of building an expensive-to-construct but easy-to-maintain heavy duty highway system, which would have the advantage of providing low user costs and needing very little maintenance and repair. But this alternative also will provide an unsatisfactory return on investment, because a government with limited capital resources will not be able to construct enough miles of road to meet the needs of the area. How, then, can the various desirable qualities of these two extremes be combined at an acceptable cost? The 12 research reported in this thesis indicates that in many cases the best approach is to initiate a long-range highway construction plan with relatively many miles of low quality road and then to improve those roads as traffic on them increases. This is known as staged construction. The staged construction'of a low volume road is the process whereby a road is initially built to a level sufficient to meet the immediate requirements of traffic and at a later date is reconstiuc••ed to a higher standard in order to decrease the costs borne by the increased traffic. Staged construction may include changes in surface type, changes in alignment, an increase in the number of lanes, and other changes to the road or its environs. The reason that the stage construction strategy is most appropriate to developing areas is that when a road is built through an underdeveloped area it is at first not very heavily used. The explanation is quite simple. Since there never has been a road from point A to point B, people in A and B have not established a social or economic reliance on one another. After the slow start, however, it has been found (Haefele (48)) that as people take advantage of the opportunities the new road provides, commerce between the vertices--and thus traffic--increases rapidly. Since there will be few vehicles traveling the road in these first slow years, the total road user costs and the maintenance expenses will be relatively low. Later traffic increases will permit relatively lower construction expenditures in terms of unit costs of transport. 2. Problems of Staged Construction Staged construction has been used in almost every road now in existence, but this construction has not followed any carefully analyzed long-range plan. The costs of analyzing staged construction alternatives are too high; too many skilled man-hours are required to do an adequate job. Few engineering feasibility reports even mention the possibility of planned staging, and when they do it is often in the context of suggesting the upgrading of a previously constructed road. Another reason for the lack of long-range construction planning may be that there does not exist sufficient fiscal stability in many developing countries to permit planning intervals of any great length . If this is so, then the role of staged construction will necessarily be minimal. However, the development -of techniques to find low cost staging strategies is likely to increase the interest of international lending agencies (such as A.I.D. and the World Bank) in staged construction, and the stability provided by these agencies should be sufficient to produce the confidence necessary for long-term planning to be undertaken. 3. Economic Issues in Staging The goal of staged construction is to increase the effectiveness of road investments by the closest possible matching of the properties of the road and the needs of the traffic at each point in the analysis horizon. Some reasons why staged construction-can be used advantageously in highway planning are: 1. It permits a lower initial investment in a road, thus permitting those freed (unused) funds to be utilized in other productive endeavors, either within the transport sector or in other sectors of the economy. For instance, the funds thus freed could be used to construct several roads in an area rather than just one. Thus a limited amount of money could be spent over a comparatively large mileage of low type, but adequately designed, highways (Taylor (59)). 2. It reduces the initial requirements for other scarce resources such as skilled manpower and equipment, and permits the use of these resources on other projects. This savings of resources is due to the shorter time required to build a lower standard road and the lessened need for specialized (i.e. expensive and imported) equipment and labor to construct the simpler road. 3.. In cases where expected traffic increases do not occur, an initial low standard road would entail a lower opportunity loss than would a high standard road because of the smaller investment in the low standard surface. Conversely, if traffic should increase more than was anticipated, upgrading would only require moving up the original construction schedule, rather than a redesign of the road. 4. Finally, staged construction contributes to im- proved pavement performance (in the case of asphalt and surface-treated roads) because irregularities that develop--for example, consolidation of the subgrade--can be incorporated as improvements in the next upgrading. In general, this would be cheaper than performing the type of ma3or maintenance which would normally be required if these defects appeared in an "original" surface. But staged construction also has several disadvantages. Among these are: 1. There may be higher road maintenance costs in the years immediately following construction of the firststage earth or gravel road than would be experienced if a surface-treated or asphalt surface had been built. 2. User operating costs on the lower quality roads would be greater. This is due to the speedier deteri- o.ration of these types of roads and the consequently higher roughness values (Moavenzadeh (38)). Because of the high discount rates (10-15% per annum) often used in evaluating low volume road projects, these increased costs can have a disproportionately great effect on the net present worth of the road. 3. The total undiscounted construction costs of roads which were initially constructed to the higher standard will usually be less than the costs of constructing the road in stages because of lost economies of scale. 4. Use of Staged Construction in Project and Systems Analysis One problem in finding an optimal construction staging strategy is that when performing project, as opposed to system analysis, the planner often assumes that the project is an isolated road, forgetting that it a larger transportation network. is really a link in The optimal staging strat- egy for the road when it is considered by itself will often be quite different from the optimal strategy for the road when it is viewed as one part of a whole network of inter- connected transport systems. Failure to take this into account may cause the improvements to one road to lead to a rerouting of traffic in such a way as to cause either the under- or over-use of other,parts of the transportation system (M4anheim (37)). The model developed in this thesis can be used to examine the impact of changes in the demand equations on all road-related costs; as network effects are most often expressed as changes in the demand equations, the method presented here for investigating staged construction alternatives should prove to be an aid to highway and network planners, even though it is primarily a tool for project analysis. 5. Determining Optimal Staging Strategies One of the difficulties associated with determining the optimal staging strategy is the high cost of examining enough alternatives to be reasonably sure that the optimal strategy has been included in the solution space. Unfor- tunately, this is a situation where it is hard for rules-ofthumb such as common sense or previous experience on similar projects to approximate the answers required.. What is needed, then, is a relatively accurate, but relatively inexpensive, means of determining the costs and benefits that accrue to a large number of alternative staging strategies and selecting the one which is best. This thesis will present a computer program which will perform this task. The thesis presents a computer program for aiding in the selection of optimal investment strategies for roads in developing nations. It discusses the factors that led to the development of the model, the structure of the model itself, and the interaction of the model's major components. Finally, it presents a report of the actual use of this model in planning for a low volume road through the Bolivian Andes. Chapter Two Review of Literature This chapter will present a review of the literature on staged construction techniques for highways. A variety of approaches, methods, and decision criteria have been formulated to evaluate staging strategies. The strategies range from simple pavement upgradings to those that involve successive alignment, drainage, embankment, and surface improvements. Decision criteria generally used in these studies include net present worth, benefit/cost ratio, and internal rate of return. 1. Staging Techniques Richard Bauman's report (1) concerns itself primarily with the forecasting of stage construction levels for emerging countries. He has presented two basic prescrip- tions for the staged construction of a low volume road. For the first method, the initial stage would have natural grades, however steep, with sharp horizontal curves on an earth road. In the succeeding stages, the gradient or vertical alignment and the degree of curvature are progressively decreased and the road surface improved with a higher quality surface such as gravel or some type of asphaltic concrete. This method has one outstanding advantage; that is, 20 it permits the construction of a low volume road at a very low cost. However, it has serious disadvantages. First, the expense of the succeeding alignment changes will be quite high. (This expense would, of course, be in addition to the regular cost of pavement upgradings.) These changes will become prohibitively costly in rolling or mountainous terrain. Also, because this method leaves steep grades, sharp curves, and rough surfaces on initial roadways, the road user costs at this s.tage will be quite high. could be extremely critical to development if growth is This traffic curtailed by high operating costs. The second method of staged construction that Bauman describes would entail initially constructing the road to the same alignment and surface characteristics as the first method prescribes for stage one. For the next stage, how- ever, the roadway alignment would be constructed to its final alignment standards, including small gradients and large horizontal curves, but still having a low or medium type surface. Successive stages then would consist of pavement upgradings only. The distinct advantage of this method of staging is that only one alignment change is required. By reducing the number of alignment changes, there is no wasting of the old roadway surface; the old surface can be utilized as an improved sub-base to the newer surface. Bauman concludes that the second method is the one which is predominantly used in countries utilizing stage construction techniques principally because the total costs of this strategy, discounted over its service life, are less than those incurred with method one. Bauman mentions one more possible staging method. This method is to construct stage one to the ultimate alignment standards but with a low type surfacing. All subsequent stages would be concerned with pavement and possibly drainage adjustments. The idea here is to eliminate or at least reduce alignment changes. By constructing the base, sub- base, and surface to the final grade and alignment once instead of changing them many times, sizable savings are realized. By delaying construction of the final surface course, savings are realized since construction and maintenance costs of the surface courses amount to 30 or 40 percent of the total costs of the road (Bauman (I)). 2. Stayed Construction: Specific Highway Techniques This section reviews some staging techniques that have been suggested by Robley Winfrey (19) for use in conJunction with the Interstate Highway System. Winfrey has investigated whether it is most economical to build the full four lanes of a four-lane divided highway or to construct only two lanes at first, which are to be followed some years later by the remaining two lanes. 22 Winfrey focuses his investigaticn on a specific project (an Interstate Highway in Virginia), using net present worth as his measure of effectiveness. He seeks to determine which parts of the road should be constructed along with the initial two lanes, and which parts should be constructed during the subsequent expansion to a full four-lane highway. In the case that he is investigating, Winfrey decides that at the time of the initial two-lane construction all the rights-of-way which would eventually be used for the four-lane road should be purchased, the roadway should be graded for the full four-lane width, and all drainage facilities and the major structures such as He makes this bridges and interchanges should be built. decision after concluding that, in this particular application, these measures would represent significant economies of scale. The right-of-way would increase in value over a period of time, so delay in purchase would mean increased expenditures; the major structures, drainage facilities, and gradings would incur large setup charges if constructed seperately from the initial two-lane road. Also, providing these items at a later date would probably cause delays to road users and create hazardous driving conditions during construction. What is the optimal interval between the initial construction and the subsequent upgrading? 23 Winfrey's approach to this problem is to determine the year in which the net present worth of all road-related costs would be greater for the four-lane road than for the two-lane road (fig. 1), as savings will accrue if.the remaining construction can be delayed beyond that time. However, factors such as con- gestion may make it impossible to wait this long, and if this is the case he quite sensibly recommends going ahead and building the four-lane road immediately. 3. Staged Construction as Practiced in Developing Nations This section will discuss some examples of the use of staged construction of highways in developing nations. Ex- amples of decision rules and measures of effectiveness for road construction in stages will be given as they have been used in several nations. As a specific example of staged construction in a developing country, Bauman (1) presents some standards for staging used in Nigeria. The data for his analysis is from Transportation Coordination by C.B. Thompson (2). Apparently, it is common practice in Nigeria, on a low voltume road, to start out with an unpaved road and to improve the road surface as traffic volume increases. For low traffic roads, between 100 and 300 VPD, the first stage improvement from an earth road is to a 12 foot wide bituminous surface treatment placed on a 20 foot base course. As further increases in traffic volume occur the width of 24 20 15 10 Years to Second Construction Costs of Staged vs. Unstaged Construction Figure 1 25 the surface treatment is increased to the full 20 foot base course. Finally, when the volune of traffic reaches 2,000 VPD, the road is surfaced with hot mix asphaltic concrete. Bauman does not indicate how these particular volumes were determined to be the critical volumes. Also, possible alighmert changes were not considered as part of the staging strategy. Unlike Winfrey, Bauman does not explicitly dis- cuss the element of expense in his description of his criteria for determining stage construction levels. Another example of the stage construction technique for highways is offered by Bonney (3) concerning a transporattion study in Sabah, Malaysia. Bonney uses net present worth of road costs as his criterion for determining stage construction levels. Bonney reduces all costs to annual costs per mile of roadway for the sake of comparison. He calculates this annual cost by straight line depreciation of the fixed facility, including interest charges of six percent. A feeder road was considered to have a ten-year life with no salvage value while a trunk road was considered to have a 20 percent salvage value at the end of its twenty-year life. Equations indicating the maintenance costs of earth and gravel roads in terms of VPD were derived. The main- tenance equations in a/mile/year for earth and gravel roads 26 respectively are: maintenance costs = 264 + 16 VPD maintenance costs = 496 + 13 VPD Bonney posits that vehicle operating costs for earth, gravel, and bituminous roads are in the proportion 2.0: 1.2: 1.0 respectively. The total cost per road transport mile was calculated as 13 cents for bituminous roads. This works out to 26 cents per mile for earth and 15.6 cents per mile for gravel roads. These costs are an average for all vehicles using the road. According to Bonney, at 25 VPD the total annual costs on earth and gravel roads of good alignment are: earth: $ 940 (construction & maintenance) + $1790 (vehicle cost) = $2730 gravel: $1585 (construction & maintenance) + $1070 (vehicle cost) = $2655 Using this line of reasoning, since the costs are nearly the same it becomes worthwhile to provide gravel roads when the traffic reaches about 25 VPD. Continuing this analysis, Bonney determines that at 80 VPD the total costs of bituminous trunk roads are approximately equal. He therefore suggests that it is worth- while to upgrade a trunk road from gravel to bituminous surface at a traffic volume of 80 VPD. There are several difficulties encountered in using this type of break-even analysis. 27 The most important drawback is Bonney's use of undiscounted costs and the consequent disregard for the time-dependent nature of highway investments. This in turn will often lead to non-opti- mal investment strategies. However, it may be argued that this drawback is outweighed by the advantages offered by a model so simple that it requires very little computational effort. The World Bank Study (4) does not present any data concerning stage construction of earth and gravel roads, but data is presented for varying qualities of bituminous pavements. For predicted volumes of 800 VPD, a low-type bituminous pavement, for example a single surface treatment, is recommended. For traffic up to 2,500 VPD an intermediate type pavement such as multiple surface treatment or a cold mix layer is desired. Finally, a high-type pavement like a regular hot mix layer is recommended for volumes greater than 2,000 VPD. Unfortunately, the criteria and calculations used in arriving at these decisions are not presented in full. A report by the Road Research Laboratory (5) indicates that a six-inch base overlaid by a single surface treatment is adequate for up to 150 commercial VPD. JWhen traffic increases above 150 commercial VPD it is recommended to add a two-inch layer of asphaltic concrete pavement. It is not stated in the report how the particular staging levels were reached. 4. Staged Construction: Pavement Design Two frequently referenced sources for pavement design information are the Asphalt Institute (6) and the British Road Research Laboratory (5). The Asphalt Institute method has been used in staged construction of high volume highways in North America. Bauman (1) has observed that when this method is adopted by emerging countries, over-design results because the method seems to be inaccurate at low volumes of traffic. The method formulated by the British Road Research Laboratory, however, has been used with considerable success in various parts of the world. The method was devel- oped for used in emerging countries and its use results, according to the Laboratory, in a "realistic design." 5. Empirical Models Thrower and Burt (7) examine the possibilities of stage construction for road pavements. They feel that con- crete pavements, since they have such a long initial life, are unlikely to be considered for staged construction, and so they have limited their discussion to flexible pavements. Thrower and Burt consider the main problem of staged construction to be minimizing the total costs of construc- tion and maintenance of a pavement over a given period o-f time; they do not mention user costs. They present four alternatives for determining when to begin the second stage of construction. Case 1: Add the second stage when the first stage has Just reached to critical value (dc) of permanent surface deformation.* Case 2: Add the second stage when deformation of the first reaches a fraction s of the normal failure value (dc). Case 3: Add the second stage using criterion given in Case 1, but assume first stage, because of excessive deterioration, plays no further structural role. Case 4: Add the second stage when the road is in the same state that it is expected to be in at the end of the analysis horizon (i.e. after the last stage is ready for repair). Thrower and Burt use these four cases of stage construction to compare their costs to those of a single stage construction for the same overall life. The sensitivity of these costs to traffic growth rate and financial discount rate is *The usual criterion of failure for flexible pavements in Britain is the occurrence of 1" permanent vertical deformation in the near side wheel track, measured from the original level. 30 also investigated. In their evaluation of the four cases, the authors comment that Case 1 is the most optimistic assumption for flexible construction. Case 2, although less optimistic than the first case, still has less total material costs than for a single stage construction. Case 3 is a more pessimistic model for flexible construction. In contrast to the two preceding cases, total material costs are always higher than for single stage construction. Finally, Case 4 is often more pessimistic than any of the preceding. It al- ways results in an increase of total material costs. A method has been suggested by Hewit (9) to use a benefit-to-cost ratio, with VPD as the variable to determine at what time it is economically feasible to improve a road surface. The benefit/cost ratio is defined as the difference in road user savings divided by the difference in highway costs, which include the cost of construction and maintenance. In a sample situation, Hewit attempts to determine at what volume it is necessary to improve a road from gravel to a bituminous surfacing. Construction cost for the new bi- tuminous surface road consists of the following items: preparation of the road bed, leveling course, base course, and the bituminous surfacing. Drainage, alignment, grades, etc., are considered adequate on the gravel road and therefore no improvements are necessary. The decision rule used in this instance is to build a bituminous road when the benefit/cost ratio becomes one. The equation used to determine this point in terms of VPD of heavy vehicles such as trucks and buses is B/0 = AR AHl = RG- RB HB-H G where AR is road user savings and AH is the cost of providing a bituminous road. The other variables are RG = 365 * VPD * $.34 RB = 365 * VPD * 0.28 HG = 408 * VPD * $.22 HB = $2,783 + $310 = HB1 + HB2 HB1 = Amortized cost of bituminous road over 20 years HB2 = Annu.1 maintenance cost Solving this equation with VPD as the variable, it was found that the road user savings are Just equal to the annual cost of improvement less savings in maintenance cost when the traffic reaches 116 VPD. This means that it would be economical to improve a gravel road to one with a bituminous surface when the truck and bus traffic exceeds 116 VPD. The major disadvantage of this method is the use of the benefit/cost ratio as a decision criterion. This method is subject to several flaws, most notably the conceptual 32 difficulty of comparing the benefit/cost ratio of a set of projects having varying design lives (11), and the diffi- culty of incorporating budget constraints into one's analysis (37). Also, this method fails to take into account the variation of user costs with deterioration of the pavement. 6. 'Mathematical Models for Staging The previous sections have presented a brief discussion of the advantages and disadvantages of staged construction for highways and have presented some examples of its use in actual road building situations. This section will review the literature that has dealt with the question of how to arrive at an optimal staging strategy. The literature is from fields as diverse as the selection of stocks for an investment portfolio to the planning of a telephone system. 7. Facets of the Problem: The Timing Issue Construction staging has been described (Marglin (12)) as a two-part problem: selecting a timing strategy and selecting a design. A third, closely related, problem is, given a set of projects and a limited budget in any one period, deciding what projects should be selected for construction in that time period (10, 11). Some authors have assumed that such projects are mutually independent (17) for ease in computation, while others have acknowledged the interde33 pendency of projects in their analyses (36). Marglin (12) offers one of the more complete discAssions of the timing problems. He identifies the major issue as the extent to which costs and benefits vary with the date of construction. He gives a decision algorithm for selecting projects for construction if the time flows of cost and benefits are known and there are budget constraints in every construction period. The algorithm, how- ever, is useful only in the case of independent projects. Several other authors also consider the timing issue with regard to independent projects. Mori (10) and Gul- brandsen (17) have developed dynamic programming computer programs for finding optimal construction schedules for sets of independent projects. The approaches of Marglin, Mori, and Gulbrandsen are quite effective with regard to computational efficiency and project mixes. However, they assume that each project is the optimal feasible alternative on any given link, and that the time stream of costs and benefits is known with certainty. The assumption is also made that the preferred alternative on any link remains optimal regardless of the status of the rest of the network. This assumption would imply, for instance, that an access road to a small village would be equally effective whether or not a connecting link was built to the market town. This is quite obviously not true, and this is one of the reasons that a pure timing approach is not satisfactory in this context. 8. The Design Issue Manne (13) has considered in some depth a related problem concerning the selection of an optimal plant size and location for three industries in India given constant annual increases in demand, substitutability of imported goods at a known shadow price and economies of scale for plant capacity. Using these assumptions he finds that new plant capacity should be added every n'th year, where for any set of initial conditions n does not vary with time and the additional capacity is equal to the initial plant size. As part of this work, Manne and his co-workers developed a computer program to determine the optimal investment strategy and plant location(s) of these three industries. If this concept could be used in highway planning it would be a relatively simple matter to design and implement a computer program or other algorithm for finding staging strategies for road construction. Manne's approach for esti- mating the cost (both initial and operating) of a facility was of the form C = a + b* Vk where a, b, and k are empirically determined constants and V is the annual production capacity of the facility. Unfortunately for road planners, however, it appears that no similar relations exist for estimating the costs of road construction. 35 9. Budget Constraints Ochoa-Rosso (16) formulates the multi-period investment model as an integer programming problem. *He is concerned with investment strategies for networks and considers the relationship between links but does not indicate how one can optimize a single project. Nashlund (27) expresses the multi-period investment model as a linear programming problem, in his case dealing with the problem of selecting stocks for an investment portfolio under uncertainty. Of particular interest is his discussion of the selection of a measure of effectiveness, which iS based upon the values of the dual variables of the linear programming solution. The paper by Lack et al. (37) also has some bearing on the subject of staged construction; it describes a computer program which examines sixteen possible road designs. Mod- els for estimating construction, maintenance, and vehicle operating costs are developed and a dynamic programming algorithm is used to find when and what designs should be implemented. Limitations on expenditures have been incor- porated through the use of LaGrangian multipliers. model seems to be constructed quite well. The However, the relatively simple cost estimating routines weigh against its use in developing nations, especially as the cost models are derived from Australian data and are, in the case of maintenance and user costs, in the form of regression equations. Because of this it would be relatively diffi- cult to transfer this model intact from area to area. 10. Staging Under Uncertainty Pecknold (36) presents an excellent analysis of staged construction of transportation networks. He considers both network and project desgin, staging and the question of uncettainty in the analyst's estimates of the future. velops the staging problem as a set of sequential He dedecision trees and then, using various decision rules, prunes branches from the decision trees. He then goes on to pro- duce a model of the sequential decision making/ investment staging process. The model operates using Bayesian proba- bility techniques to update the tree under uncertainty. 11. Summary The models for formulations of staged construction which have been reviewed for the most part deal with trans- portation networks or other large scale-systems rather than with the design of a single link and the subsequent increase of capacity or cost of that link. This is particularly true for the models of Gulbrandsen, Mori, and Ochoa-Rosso, and true to a lesser extent for the models presented by Lack, Manne, and Marglin, whereas the primary concern of this thesis is the allocation of resources to a single road project. 37 One other difficulty is that these studies (except for Pecknold's) are deterministic in outlook. It is felt that due to the large demand road projects place on both the foreign and local capital reserves of a developing country more information should be presented to the decision maker than is offered by deterministic analysis. 38 Chapter Three Developing the HCM This chapter will report on the actual process used in developing the Highway Cost Model, the technique which was structured to give highway planners in developing countries an easily used tool for determining optimal low volume road investment strategies under conditions of uncertainty. 1. The Basis: Cost Estimating Routines The basis for the model grew out of previous work aimed at developing a cost estimating routine for low volume roads. This study, sponsored by the International Bank for Reconstruction and Development, resulted in nine FORTRAN programs which moeeled the processes involved in low volume road construction, maintenance, and user operating cost (36, 38). The construction routines are called HWYCT, EARTH, and RFETH. HWYCT computes 1) pavement quantities and costs, using a geometrical approach, 2) the length in meters and distribution of various sizes of culverts, using a model developed by Lago (53), and 3) calls either EARTH or RFETH to estimate earthwork volumes. EARTH is called if a one- point model of the terrain and final road profile is provided by the model user. When this occurs, an estimate of earthwork is made, assuming a zero side slope. The quanti- ties of cut, fill, and borrow are returned by EARTH to the routine HWYCT. If contour-line crossing data is supplied rather than the one-point terrain descriptor, routine RPETH is called. Using relationships determined in a study for the Department of Transportation performed by Soux (51), it estimates earthwork quantities as a function of average and maximum desired grades oi the road and the number of tenfoot contour lines crossed by each kilometer of the road. It is not as accurate as the one-point model but the data necessary to use it can often be gathered at a considerably lower cost and without knowledge of the details of the final alignment. When control returns to HWYCT all costs are summed and miscellaneous and supervisory expenses are added to this qu atity. See Appendix D for a further dis- cussion of these routines. These routines are used both in estimating the costs of initial construction and for reconstruction of the road. In the latter case, if the road cross section remains unaltered, the earthwork routines are not called. The maintenance costs are estimated by a set of routines designed by John Alexander. A complete description of these programs is included in reference (36). Essen- tially, these routines estimate deterioration of the road surface and then compute the work necessary to restore 40 some measure of the lost serviceability. Estimates are then made of the roughness in inches per mile, the coefficient of friction, and the rolling resistance of the road surface. This is done within routines MAINT and DETER. Other aspects of road maintenance are simulated within routines SHLDR, DR4NT, and VEGT, which compute the shoulder maintenance, ditch cleaning, and roadside clearing efforts respectively. MCOST sums the costs of all maintenance ac- tivities and returns these values broken down by activity to MAINT which then returns to NETWR' . The road user operating costs are estimated by the subroutines USER and LOOK. The former computes running speeds, labor, fuel and equipment usage, costs, depreciation and fixed charges on the vehicles on the basis of user-supplied information and data collected explicitly for this model. LOOK is used to interpolate within tables of data developed by de Weille (52). It should be noted that these models are rather extensive and although not tested in a production environment are fairly accurate when compared with engineering feasibility studies, through comparisons made with data supplied by the British Road Research Laboratory (57). 2. Developing the HCM It became apparent that these routines, although they comprised a useful tool for estimating the costs accruing to a single road design, were not a completely successful tool for investigating staging strategies, primarily because of the difficulties associated with communicating with the model. In terms of stage construction the model was awkward to work with--i.e. it could only examine one strategy at a time, and a great many cards were required to define a strategy. In evaluating a model of this nature, it was decided that heavy consideration must be afforded to the model's relationship with its ultimate user. The ultimate user of the Highway Cost Model would be highway planners in developing nations and, to a lesser extent, officials of the U.S. Department of Transportation. It was felt that neither group would be very eager to use the model if it required more than minimal knowledge of computers. This posed two main problems: first, developing a method for finding optimal investment strategies under uncertainty and second, developing a means of communicating with the model user which was independent of his knowledge of computers. Thus, the Highway Cost Model was conceived around the idea o-f building a "black box". The user would be able to throw data into it, receive his answers, and not necessarily be concerned with the internal mechanism of the model. addition, the technique being developed had to rely upon 42 In the cost estimating routines developed previously. These routines represented a great wealth of research experience on low volume roads. 3. Selecting an Approach: The Alternatives Four methods were considered for using the cost estimating routines as a means to determine optimal investment strategies for low volume roads. The first method considered was to use some form of network analysis such as GERT (Pritsker (56)). This ap- proach would have meant simplifying the cost estimating routines so that they would fit into the relatively simple structure that GERT provided, thereby losing much of the hard-earned accuracy that had been attained. For this reason, the network analysis approach was rejected. The second approach considered was to use dynamic programming (Wagner (60)) and modify the cost estimating routines so that they were compatible with the d.p. algorithm. This approach had one major advantage--within the accuracy permitted by the cost estimating routines, the optimal solution would certainly be found. However, this advantage was counterbalanced by the very large number of iterations that would be necessary to solve this algorithm and the consequent high computer charges associated with devoting large quantities of computer time to a single run. Further- more; using a d.p. algorithm would cause the model to ex- amine so many alternatives that only summary cost figures could be presented unless the model user was to be inundated with a flood of computer output. In view of these disadvan- tages, the dynamic programming approach was also. rejected. The third approach invplved altering the cost estimating routines so that they would be compatible with linear or nonlinear programming techniques. The major advantage of these techniques was that they automatically incorporated resource constraints; a considerable literature existed describing the use of these techniques in capital budgeting. The difficulty with using the linear and nonlinear programming techniques is that in order to keep the measure of effectiveness and constraints simple, it would be necessary to limit them to only fiscal factors. In order to increase the number of factors considered beyond the simplest fiscal concerns, it -would be necessary to develop an extremely complex set of constraints and a similarly complex measure of effectiveness. Either alternative was unacceptable. The fourth approach consisted of adding a set of translating and control routines to the cost estimating routines. The function of the translating routines would be to take a set of simple commands from the user and convert those commands into a form that would be used to control the cost estimating routines. Using this approach, the planner could draw upon his experience and knowledge to guide the model and make up for whatever inaccuracies and biases it contained. The disadvantage of this approach was that a truly optimal staging strategy would probably not be arrived at unless a very large number of strategies were specified and examined. But this disadvantage was reduced in importance when it was noted that the cost estimating routines were not accurate enough to justify the expectation that even an exhaustive analysis would result in a truly optimal situation. This last approach had several advantages. Only minor modifications would have to be made to the cost estimating routines, and consequently the accuracy of the model would not be reduced. Also, in letting the model user retain control of the strategies that were investigated, this technique encourages the model user to have more confidence in the answers which the model offers. Finally, as the output of the model would be a summary of the consequences of the various strategies, and not a ranking of the strategies, it would permit the user to choose any measure of effectiveness he desired in evaluating the various strategies. This approach, then, permits the model user to find a near-optimal solution by making several runs with the model; on the first run he would normally examine a wide variety of staging strategies, while on subsequent runs 45 he would select the most promising alternatives from previous runs, modify certain timing and design parameters, and determine whether the new strategies are superior. The user could stop whenever the improvement in the measure of effectiveness went below a certain level. At this point he could subject the best strategy to conventional analysis. Thus the model user never loses control of what is happening, and he can compensate for resource constraints and/ or his own measures of effectiveness. It was concluded that this approach was the most nearly suited to the development of the Highway Cost Model. The selection of this approach made necessary the design and implementation of a set of translation and control FORTRAN routines that would interact with the previously written cost estimating routines. Some of the factors that influenced the design of these routines were: effic- iency--the routines should use as little space as possible for storing of temporary results, yet they should also permit a reasonable number of strategies to be examined during a single run; speed--the routines should save as many results as possible so that they would not need to be frequently calculated; minimization of input and output--in order to reduce running time, the attempt was made to decrease the number of cards required to specify staging strategies and increase the amount of information that was 46 always written out; and finally,, elegance--the model as viewed by the user should be simple to operate yet sophisticated in terms of its capabilities. Once the translating routines were written, a control routine was designed and implemented. The function of this routine is to use the list provided by the translating routine so as to cause the cost estimating routines to evaluate the staging strategies specified by the user. These routines, combined with the cost estimating routines developed previously, becamse the Highway Cost Model. 47 Chapter Four The Computer Routines This chapter discusses the computer routines of the Highway Cost Model. The routines are composed of two inter- acting groups of FORTRAN subroutines. The first group is a set of ten routines for estimating the costs of construction, maintenance, and vehicle operationi the second group is the staging routines, which act as an interface between the model user and the cost estimating routines. These staging routines permit the model user quickly, easily, and inexpensively to examine the costs accruing to up to thirty alternative staging strategies under an infinite variety of traffic conditions, for an analysis horizon of up to twentyfive years. A further function of the staging routines is to display the consequences of the various staging strategies in a straightforward and readily comprehensible fashion. Since the HCM has been designed as a working tool for the highway planner, this is an important consideration; a poor format will discourage the planner from using the model. For this reason a good deal of time was expended in refining and simplifying the structure of the output. 1. The Staging Routines There are five main subprograms in the staging routines: they are MAIN, NETWRK, CONSTR, STRAT, and SAVDAT. MAIN, despite its title, is a small routine which determines the 48 level of detail presented in the output. MAIN also calls several subroutines: PMIN, which reads in the problem description; STRAT, which reads and interprets the staging strategies; and NETWRK, which steps through the decision network. A flowchart for MAIN is given in figure 2. STRAT is a considerably more complex routine than is MAIN, but it performs fewer functions. STRAT reads the number of staging strategies to be examined during the current run, the number of road designs which are being altered, and the number of years in which construction costs or productivities are different from those in year one. data is read from a single card. This If the model user wishes to add to or alter the "typical" templates and pavement cross sections stored in the array DESIGN in the BLOCK DATA subroutine, STRAT will read in the number of changed designs and termporarily store them in the appropriate locations. STRAT also has the ability to read in the construction costs and productivities that are expected to be in force over the analysis horizon. Thus, increased costs due to in- flation and change in productivity can be included in the analysis and in comparing alternative investments. By far the most important function of the STRAT routine is reading in the various investment alternatives and interpreting this information (which is presented in a manner analagous to a decision tree) into a form which is used 49 Figure 2 Flowchart for MAIN @B 50 A Q) by NETWRK and CONSTR in stepping through the decision tree. Briefly, this consists of 1) recognizing nodes in the decision tree, 2) counting the branches from each node, and 3) converting the branch data into numbers defining the construction alternatives. A flowchart for this routine is given in figure 3. NETWRK is the most important routine in this group. It calls the cost estimating routines, performs bookkeeping, and steps through the decision network defined by the user. A flowchart for NETWRK is presented in figure 4. A further function of this routine, and one that is of considerable importance to planners, is its capability to examine the consequences of uncertainty in traffic projections. This is done through a loop that encompasses the entire routine. When there are two or more estimates of the traffic, the cost accruing to each is weighted by the probability of that estimate's occurring, and used to find the expected costs of the various construction alternatives.. The equation used to find the expected cost where E = expected cost n = number of traffic sets set i Pi = probability of realizing traffic Ci = costs accruing to traffic set i is: n = (Pi * Ci) 52 Figure 3 Flowchart for STRAT A determine # of construction activity i ............. create list of constuction activity locate nodes in list of construction activity print list: construction activity, nodes, strategies Figure 4 Flowchart for NETWRK determinis tic traf. prediction 55 0 this is a network problem C- )57 compute foreign exchange components of maintenance and operatin2 costs Ft H locate the node corresponding to this construct*on weight array CSTRT by PNTPMF, add this quantity to array STCST 0 0 I 60 NETWRK steps through the decision tree by using the list of staging strategies produced by STRAT. Two indices are kept by NETWRK: one for the year that is being simulated and another for the staging strategy being examined. Each time the year index is incremented NETWRK checks whether the period in question is a construction period, a node, or the end of the analysis horizon. CONSTR is called. If construction is required, If a node is located, the costs and traf- fic at that node are saved by SAVDAT. If the end of an analysis horizon has been reached, SAVDAT will print summary costs for the investment, examine the list of construction alternatives for the next strategy, and restore the costs and traffic at that point (the beginning of the new strategy.) SAVDAT has two functions: 1) to list and 2) to restore the properties at a node when called by NETWRK. The para- meters passed to this routine define the node, and establish whether a save or restore operation is to be performed. The information saved is a complete description of the road at the time SAVDAT is called. This includes costs to date (discounted and undiscounted), the road template and cross section, traffic levels and operating costs per kilometer, and the material and currency consumption required by the previous construction activity. A flowchart for the SAVDAT routine is given in figure 5. CONSTR performs the same type of bookkeeping and Figure 5 Flowchart for SAVDAT TYPE is set by NETWRK 62 control functions as are done by NETWRK. Specifically, CONSTR takes from the BLOCK DATA subroutine details of the road template and cross section, selects the costs appropropriate to the year in which construction occurs, and then calls HWYCT to compute the costs of construction. When control returns to CONSTR, costs, material quantities, and earthwork volumes are summed and printed. Surface con- ditions such as roughness and frictional coefficients are initialized by a call to INITL. Subsequently, the foreign exchange components of construction costs are computed on the basis of material, labor, and equipment expenditures. CONSTR can, if desired, cause PMIN to read in a new set of vertical points of intersection (VPI's) and topographical data. This information is written over the cur- rent data sets and used in further analyses. This permits the user to examine the consequences of constructing roads on different alignments. A flowchart for this routine is given in figure 6. 2. Relationship to Cost Estimating Routines Although the previous section has given a brief indi- cation of how the network routines are related to the cost estimating routines, this section describes in a more explicit form both the calling sequences and the information passed between the two sets of subroutines. Figure 7 shows the calling sequences used in the HCM. 63 Figure 6 Flowchart for CONSTR write identification construction JQ is the design number A 0 TOP is the type of~construction initialize array RCOND 0)65 B Figure 7 Calling Sequences line indicates hat does not ·ily occur. To read it, start at MAIN. The order in which the routines are called is given by the clockwise arrow. Thus, routine MAIN calls PMIN which may call FORIN (if foreign exchange requirements are to be read). MAIN will then call STRAT and NETWRK, which in turn will call CONSTR (or SIMCON if a single investment strategy is being examined). When con- trol is returned to NETWRK it calls USER and MAINT to find the costs of vehicle operation and road maintenance. The year index is then incremented by one, and a check is made to see if a node or construction perid has been reached. If this has occurred, NETWRK takes the appropriate action-- calling CONSTR to simulate road construction, or, in the case of the node's being reached, calling SAVDAT to save the conditions at the node. 3. The Highway Cost Model Flowchart Figure 8 presents a macro flowchart for the entire Highway Cost Model. It shows the flow of control in terms of issues, decisions, and operations in a format which is not directly related to the formal (i.e. FORTRAN language subroutines) structure of the HCM. As can be seen in this figure, the major issues considered here are the tradeoffs between different maintenance, construction, and vehicle operating costs, the effects of uncertainty in traffic projections, and the need to communicate with.the model user. It is hoped that the simplicity of the input and the 68 Figure 8 Macro Flowchart 69 A a constructhis yes/ tion 1periodsl get road design and unit costs from storage no get maintenance policy from storage Ir compute costs and resources consumed in construction -- initiali7ze surface conditions -4 " [ compute road user costs and traffic make traffic projections on basis of demand curve, growth rate, and per kilometer costs B 70 C B compute deterioration of road and right of way I compute necessary maintenance effort on basis of maintenance policy and deterioration year = year + 1 store costs and traffic at this node yes • tia is this a node no G D 72 clarity of the output will make this model and the information it provides accessable to even the relatively inexperienced computer user. 73 Chapter Five Experiments in Staged Construction: Techniques and Results Several experiments were performed using the Highway Cost Model to test the hypothesis presented in Chapter One, namely that staged construction of low volume roads would reduce the discounted cc• . s•. - construction, maintenance, and vehicle operation under a variety of circumstances. This chapter will discuss the experiments that were performed.and present the results of these experiments. The experiments which were run served to develop a set of pruning rules that the model user could draw upon. These pruning rules, which embody the conclusions drawn from these experiments, make the planner's work easier as he can use these rules to decrease the number of designs and staging strategies which he must examine during the first iteration. Chapter Six will discuss the implications of these experiments for planners of low volume roads in general and users of the Highway Cost Model in particular.. 1. The Experiments One of the great advantages of using a computer simu- lation of a real-world situation is the ease with which experiments can be performed and hypotheses tested. The HCM is an excellent example of this statement; it can inexpen- sively and accurately investigate.the effects of various paramters, decisions, and other factors on the costs associated with low volume roads. Previous work with the cost estimating routines (38) indicated that the most significant parameters affecting low volume road costs were traffic conditions and terrain. Considerations of lesser importance were the discount rate, the length of the analysis horizon, and factor prices and other site-dependent conditions such as the productivity of the construction work force and the vehicle mix. In order to learn as much as possible about the effectiveness of various construction staging strategies, the following procedures were used. First, a set of feasible construction strategies were defined for a situation in which 1) reconstruction could occur only at five-year intervals and 2) the roads to be considered were earth and gravel one- and two-lane roads and surface treated and asphalt paved two-lane roads. This set of twenty-five strategies represented a fairly full range of choices available to the planners of the stage construction under these conditions. Figure 9 shows these staging strategies, presented here in the form of a tree where every path from year zero to twenty is a distinct staging strategy, with reconstruction or upgradings of a road occurring at the nodes of the tree. (For the experiments that were run, the one-lane roads were EARTH2S GRAVEL2 SURFACE ASPHALT GRA.VEL2S SURFACE ASPHALT SURFACE ASPHALT LW.J.J 44" SURFACES S ASPHALT ASPHALT ASPHALT ASPHALT ASPHRNW ASPHRNW ASPHRNW 15 YEAR: 1 The Staging Strategies Figure 9 76 removed from consideration as at all but extremely low levels of traffic they resulted in excessive unit costs of vehicle operation. Therefore, under the generally higher traffic levels normally used in the experiments, examining these alternatives would have been a waste of time.) A five year-interval between reconstruction periods was chosen because 1) the total discounted costs of construction,maintenance, and vehicle operation did not vary more than a few percentage points when reconstruction was delayed or speeded up two or three years, and 2) five-year intervals were well suited to the format used for input of construction strategies to the HOCM. It should be noted that this interval is not limited to multiples of five years; the HOCM can consider intervals of any integral number of years. 2. The Scenarios In order to examine the effectiveness of the various staging strategies they were tested under a wide range of conditions. The procedure used was to take two "base" scenarios and vary the design and cost parameters. The base scenarios were taken from two engineering feasibility studies. The first, performed by Louis Berger, Inc., investigated National Route 14 in Argentina. done by Baker-Wibberly The second, , reported on the Sapecho-Puerto Salinas road in Bolivia.( 62,63 ). 77 The two roads differed in many respects, including traffic volume, terrain, and suggested design. The Arg- entine road was asphaltic concrete, designed to carry fairly high levels of traffic on a straight, flat embankment on a floodplain north of Buenos Aires. The Sapecho- Puerto Salinas Road, on the other hand, was expected to carry relatively little traffic through the Andes, fifty Appendix C contains the miles northeast of La Paz. data which was used to represent the base scenarios of both roads. Even though these roads seemed to encompass the extremes that would be encountered by planners, it was felt that firmer conclusions could be drawn and pruning rules formulated if the staging alternatives had been examined under a wider variety of conditions. 3. Expanding the Parameters To obtain an expanded number of parameters for this experiment, the following manipulations were made to the base scenarios: the traffic volume was varied, the terrain data was switched (that is, taking the terrain data from the Bolivian site and combining it with the cost factors, designs, and traffic volume and types of the Argentine site, and vice versa), and several discount rates and analysis horizons were used. Specifically, the three parameters which define expected traffic--initial level, elasticity 7t of demand, and annual growth rate--were varied from the values given by the engineering feasibility studies; then the costs of each staging strategy was determined. Tables 1 and 2 show the traffic, growth rates, and price elasticities used for the Argentine and Bolivian roads. 4. Elasticity of Demand To test the effects of increasing elasticity of demand, a series of experiments were performed with input data identical to the base run in all respects but one--the elasticity of demand for all vehicles was increased to five percent. The total discounted costs of the twenty-five strategies for both the high and normal elasticities of demand is given in figure 10. As this figure shows, increasing the elasticity of demand caused significant reductions in total costs for the better strategies even though in some cases it increased the costs of the lower quality strategies. The changes in costs were almost completely limited to operating costs; the elasticity of demand is a factor in determining the traffic volume of the road so only slight change in maintenance occurred. In general, increased elasticity tended to make improved roads better choices, since the increased elasticity of demand generated more traffic and increased the consumer surplus on the higher quality roads. However, the increased traffic caused increases in the total costs of vehicle 79 Vehicles/Day Base Cost$/KM 15. 1.342 15. 2.405 5.370 30. 75. 75. 150. 150. 150. 300. Elasticity 0.012 0.003 0.003 0.090 0.090 0.090 0.012 0.003 0.003 0.090 0o.o090 0.090 1.342 2.405 5.370 0.012 0.003 0.090 0.090 0.090 1.342 2.405 5.370 0.012 0.003 0.090 0.090 0.090 0 .ogo 1.342 2.405 5.370 0.003 Other Growth Rates .18 .18 .18 Growth Rate Other Elasticities .045 .045 .045 0.050 and 0.0 Traffic Conditions for Bolivia Data Table 1 6O Vehicles/Day Base Cost$/KM Elasticity Growth Rate 35 0.255 0.012 0.066 15I. o0.357 2.200 2.265 0.003 0.042 0.042 16·. 9 ;. 5 i.. 170 . 75 80.• 43 . 22 . 0.003 0.003 0.009 2.366 0.042 0.037 0.066 0.012 0.003 0.003 0.255 0.357 .2.265 2.366 0.003 0.009 0.042 0.042 0.042 0.037 345 i. 0.255 148 . 157 • 0.357 0.012 0.003 0.066 0.042 0.042 44 2.366 0.003 0.003 0.009 '2.200 2.200 2.265 86 Other Growth Rates .122 .084 .084 .084 .074 0.042 0.037 Other Elasticities 0.050 .033 .021 .021 .021 .018 and 0.0 Traffic Conditions for Argentina Data Table 2 56. Q. i. O 54. .9 *O0 4.4- 0 0 + 52 0 O fl, C o 0 0 50 o oC -, +1 O 0 0 O 48 0 0 46 44 o Elastic Traffic + Normal Traffic 0co 1'5 Strategy Argentina: Costs due to Normal and Highly Elastic Traffic Figure 10 82 W m operation and thus caused the incogruous situation of gravel roads having lower total user costs that surface treated roads over the analysis horizon. (It.should be noted that this situation arose only in cases of very elastic demand. Fortunately for planners, it seems that traffic in developing nations is only slightly elastic andl so this situation is not likely to occur (Soberman (55), Haefele (48) )). 5. Growth Rate Next, the annual traffic growth rate of the base scenarios was varied. In the HOM the user generally spec- ifies this parameter as an annual percentage increase; the traffic in year n + I is given by the expression 1 Tn+1= [tin * (1. + gi/100.l where tin is the traffic in class i in year n and gi is the growth rate of traffic in class i. Due to the multiplicative nature of this parameter, small changes in it lead to considerable variations in traffic over the life of the road. For this reason, and also because of the difficulty in estimating the growth rate of traffic, three growth rates--low, medium and high-wer associated with each class of vehicle, and the effects were noted. The experiments showed that high growth rates were associated with reduced costs for high type roads, and low growth rates favored poorer quality surfaces (Figure 11). This was even more apparent when the discount rate was increased from its normal value of seven or eight percent to ten or twelve percent. Figure 11 shows the costs of the Argentine base scenario for growth rates of seven and, twelve percent. 6, Maintenance Policies The Highway Cost Model permits the model user to specify a wide range of both labor and capital intensive maintenance policies (Table 3). Six such policies--poor, normal, -and excellent capital and labor intensive maintenamce--were defined, and their effects on the utility of the various staging strategies were noted over several sets of initial traffic conditions. The tradeoff that occurs is that increases in maintenance reduce the unit cost of vehicle operation, while reductions in maintenance increase the unit cost of vehicle operation and may lead to the need for more frequent reconstruction of badly deteriorated surfaces. Because a relatively small percentage of total costs are due to maintenance activities, earth and gravel roads in both flat and rolling terrain had lower total costs when excellent maintenance policies were used than they had when poorer maintenance was given. 64 The reduced total costs + Low Growth Rate 54 . 0 * High Growth Rate . . a oo + . Oc0 0' E 4. + + 0t 4 .9. ÷ 0 s 1, ý). CD W+P t (10000's) 46 _1 5 Strategy Increasing Strategy Quality I Maintenance Policy _ Poor Capital Intensive Blading Frequency ___ Rut Fraction Filled Maximum Rut Depth cm. 1 __ __ 10,000 2.0 Normal Capital Intensive 5,000 1.5 Excellent Capital Intensive 2,500 1.0 Poor Labor Intensive* 10,000 2.0 Normal Labor Intensive 5,000 1.5 Excellent Labor Intensive 2,500 1.0 * Labor intensive maintenance is not as effective as Capital Intensive Maintenance for Gravel and Earth Road Blading Capital and Labor Intensive Maintenance Policies Table 3 86 were due to the higher velocities made possible by the increased smoothness of the highly maintained roads, and the consequent reduction in time dependent expenditures. This is shown by figure 12 which gives total vehicle operating costs over the analysis horizon for earth and gravel roads on the Argentine alignment for poor, normal and, excellent capital intensive maintenance. Figure 13 shows the velocity of each vehicle class on route 14 in year five for poor, normal and excellent capital intensive maintenance. The situation is slightly different for surfacetreated and asphalt roads. On both these surfaces, rela- tively little maintenance is required in the first years after construction, but in suceeding years more maintenance is required each year until reconstruction.(Figure 14). Also, due to the way in which these roads are maintained, labor and capital intensive maintenance techniques are essentially identical, differing only in such tangential aspects as ditch cleaning and vegetation control (Vance (61) Alexander (36)). For this reason both surface treated and asphalt roads exhibit similar maintenance and vehicle operating costs over the:.first seven to ten years of the analysis horizon, after which costs increase more rapidly on the surface treated roads. Therefore, an often economical 1.2 1.0 0.8 0 o 0.4 U) 0I 0.6 0.2 U.U U_ poor I I normal excellent poor Earth normal excellent Gravel Per kilometer operating costs vs. Maintenance Policy Figure 12 50 45 0 4J '40 035 O + 30 * Vehicle 1 0 vehicle 2 + vehicle 3 I SI poor normal Ir !p I excellent poor normal excellent Gravel Earth Maintenance Policy vs. Velocity Figure 13 * Asphalt + Surface Treated Reconstruction in year 18 5. 6· 35 1 . 2O Strategy Maintenance Cost of Asphalt and Surface Treated Roads Figure 14 90 staging policy is to build a surface treated road and, when the serviceability index reaches the range 1.5 to 2.0, (Alexander (36)) to build the final layer of asphalt. Experiments made with the HCM have shown that this procedure often reduces total discounted costs over a wide range of initial traffic conditions and a range of discount rates from seven to twelve percent . per year (Figure 7. 15). Discount Rates In recent years, interest rates on development loans have been increasing rapidly; where rates of two or three percent were once common, some projects in recent years have been evaluated at discount rates as high as fifteen percent. In part, these increased rates reflect the demand for risk capital; they are also partly due to the high rate of inflation occurring in many parts of the world. Several experiments were run using the HOM to test the desirability of the various strategies in view of this important factor. The experiments showed that higher discount rates made the use of staged construction even more advantageous, because the compunding of the discount rate causes future expenditures to wigh less heavily than present expenditures. Figure 16 shows the total discounted costs accruing to the twenty-five strategies on the Argentine route for interest rates of seven and twelve percent. Asterisks (*) indicate those strategies where 150. * 130 . 110. 90. C oo 3 0 , 70. O 4- c 50. V) .r4 r-4 o Asphalt road, no reconstruction E-r * Surface treated road, reconstruction at PSI = 1.5 T r Traffic low normal high low Interest= 7% • normal Interest= 12% Advantages of Staged Construction Figure 15 high 160 140 Interest Rate = 7% e S 0 a 120 0 o o o Cý -100 0 e * 0 & o 80 860 0 40 * * 6 9* 0 5 1 0 60 # * A * ** d 0 Interest Rate=12% 0 A A 40 16 15 * 20 Strategy (Increasing Road Quality) Effect of interest Rates on Total Discounted Costs Figure 16 93 * A 25 staged construction did not occur. 8. Foreign Exchange Foreign exchange consumption can often be an important factor in deciding what type of road to build. The limited foreign exchange resources of most developing countries make necessary the careful consideration of the uses to which this resource is put. Some roads will require more foreign capital than others, either because they are more expensive or because their design requires greater quantities of imported materials or equipment to build. Foreign exchange requirements are calculated in the HCM by asking the user to state the percentage of vehicle, fuel, tire, construction and maintenance equipment, construction labor, and construction material costs that must be purchased using foreign exchange. the percentages used for both data sets. Table 4 shows These percentages were used to estimate foregin exchange consumption by use of expressions of the form Foreign exchange 7 F= I• needed (unit costi a consumption i 1=1 * percent offshore costs) . exchange rate] where the subscripts refer to the seven categories described in Table 4. The way in which offshore costs varied with staging Percent Offshore Cost Item Vehicle 80. Labor 43. 0. Construction Material Fuel 70. Tires 80. Construction Equipment 100. Maintenance Equipment 100. Foreign Exchange Component of Costs Table 4 95 strategies for medium levels of traffic in Argentina is closely related to the way in which total costs varied, with the single exception that earth roads were considerably less expensive in terms of foreign exchange than the total costs would indicate. Examination of the offshore costs accruing to different levels of traffic showed similar effects. Figures 17, 18, and 19 show foreign exchange costs for the twenty-five strategies for the three traffic levels previously described. By reference to figure 9 one can see that strategies 1 through 10 were initially earth roads, 11 through 17 were initially gravel and the remainder Thus, in those cases where were surface treated or asphalt. foreign exchange consumption is an important consideration, high type roads may be preferred to poorer quality surfaces even though higher initial construction costs will be incurred. g. Length of the Analysis Horizon Because any fixed-length analysis period represents a length of time which is shorter than the total life of the road involved, any analysis of the road which considers only that period will be somewhat misleading. For example, if two or more staging strategies are compared, the length of the analysis period will affect the ranking of the alternatives. Consider the impacts of the following strategies in the case of Argentine Route 14. 96 Strategy 1 consists of 140 .130 120 110 100 1 - 1 · Strategy i5 - Foreign Exchange Requirements Argentine Route 14 Low Traffic Figure 17 97 -- 20 25 0 0 190 - .180 - O I0 0 o , 170 UO 160 O 150 140 - 1AO 5 10 15 20 Strategy Foreign Exchange Requirements Argentine Route 14 Normal Traffic Figure 18 25 320 4 O a 44 O 0 g ra O 0 B 0r (r' O 230 Br I 0r 200 1 70 5 15 10 Strategy Foreign Exchange Requirements Argentina Route 14 High Traffic Figure 19 99 20 25 building an asphalt road and giving it normal maintenance. Strategy 2 consists of initially building a surface treated road and upgrading it to asphalt in year fifteen, giving it normal maintenance throughout the analysis horizon. Given an analysis period of twenty years, it is unlikely that Strategy 1 will have lower discounted total costs. But if the analysis period is lengthened to twenty-five years, the situation may be reversed--the asphalt road will have required reconstruction and in the interim the user costs will have increased to more than compensate for the costs of upgrading the surface treated road. The costs over time of both roads would be given as in Figure 20. This implies that longer analysis periods favor roads that are reconstructed in the last half of the analysis period, while shorter analysis pFriods are more favorable to construction strategies having only a single construction activity. 10. Results of the Experiments: The Pruning Rules The experiments Just described examined the costs accruing to twenty-five different construction strategies under a very large number of conditions. As has been noted, one of the ob3ectives of running these experiments was to develop a set of pruning rules which planners could use to reduce the time and effort required to arrive at an optimal investment strategy whether or not they used the Highway Cost Model. 100 5 0 oo 0 o 4vo 0 0 u No Staging Staged Construction- 4-,i 0 -HO H( _ 1 __ 10 Year 15 Bolivia:Costs to Date of Roads both .Using and not Using Staging Figure 20 101 25 The remainder of this chapter will discuss a set of pruning rules which have been developed using as a measure of effectiveness the total discounted costs of each staging strategy. 11i. Rules for Flat Terrain For all but the lowest i.e., less than twenty-five vehicles per day over the analysis horizon, levels of traffic, growth rates, and price elasticities of demand, the lowest net present costs occur when a surface treated road is initially chosen. As traffic warrants, it may be desirable to upgrade to an asphalt road at year ten or fifteen (assuming a twenty year analysis horizon).. Discount rates greater than ten percent favor resurfacing and minimum construction expenditures in any one year. Heavy vehicle loadings' (in terms of the number of vehicles using the road and their weight) increase the desirability of an asphalt road, except at exceptionally high (greater than ten percent) discount rates. In most cases, surface treatments and resealing would s'eem to be adequate. 12.. Mo.untainous Terrain For low and medium levels of traffic, gravel roads appear to be best in terms of total discounted costs. Earth roads are acceptable in mountainous regions if traffic 102 is initially very low (under twenty-five vehicles per day) and increasing slowly, on the condition that good or excellent maintenance can be obtained. As velocity on mountainous roads is limited by the grade, asphalt or surface treated roads generally result in only small savings for road users. Unless the expected traffic is exceptionally heavy, the savings will be less than the cost of the. asphalt layer. High traffic growth rates suggest a need for better roads, but the opportunity loss due-to unrealized traffic growth and a more expensive surface may well be greater than the additional user costs due to running on a gravel surface. Unless high traffic levels are very probable, a gravel road would be preferred. Longe3 flatter routing of mountain roads (that is, going around the mountain rather than going over the mountain) may reduce both construction and vehicle operating costs if the following expression is true # km * uc/km >(# km + akm) * (uc/km - Auc/km) where # km is the original leng.th of the road a km is the additional mileage constructed on the flatter routing uc/km is the per vehicle operating cost on the original routing and 103 6uc/km is the reduction in per kilometer operating costs as a result of flatter grades If it is, the increased costs due to extra mileage will be less than the savings caused by less earthwork and lower. grades. Of course, this is very dependent on the original and alternate alignments, but as the HCM permits the use of contour line crossing data this alternative could--and should--be inexpensively explored. 13. Maintenance The experiments performed during this research suggested that capital intensive maintenance is least costly for many earth and gravel roads. However, as this course of action can lead to foreign exchange consumption, it may be desirable to use labor intensive maintenance at the expense of an increase in total costs. For the factor prices and productivities used in these experiments, it costs more do to a given amount of work using labor intensive techniques than to do the same work using capital intensive procedures. However, different factor prices and a high shadow price for foreign exchange may make labor intensive techniques preferred. The interesting tradeoff here is the ease of establishing a labor intensive work force against the increased cost of maintenance. One must recognize that, in an economy having high levels of 104 unemployment, the shadow price of labor is less than the wages paid. For example, by employing unemployed workers, one may be eliminating relief funds. the expense of providing them with For this reason, the creation of a labor intensive maintenance force may be less costly than is indicated by the HCM. 14. Pruning Rules: Other Issues Staged construction can be counter-productive unless the commitment to staging is kept. A road built with the expectation of being upgraded in ten years can be a definite hindrance to development after that date if it is not improved. Maintenance is a far more important issue than it is usually considered to be. Poor maintenance procedures and policies should not be used for more than five years at the very most, or most of the original investment may be lost due to the encroachment of vegetation, loss of surface materials due to traffic, erosion, and other factors. For this reason, effective maintenance agencies should be formed during the construction of the road, and not left until maintenance is badly needed. Finally, unless there are very strong reasons for only using one analysis horizon, the planner should examine the alternative staging strategies for their effectiveness at periods five years longer and shorter 105 than the length of the nominal analysis horizon. 15, The Use of the Pruning Rules What can the planner do with these pruning rules and why are they important to him? isthat The answer to these questions the pruning rules will make it easier for the plan- ner to determine an optimal investment strategy. This is because he can use these rules to discard a large number of undesirable strategies at the beginning of his investigation --for example, earth roads and all staging strategies deriving from earth roads--and replace them in his input to the HCM during the first iteration with a wider range of gravel and surface-treated designs, staging strategies, and maintenance policies. Essentially, the use of the pruning rules enables him to combine the work of the first and second iterations, thereby reducing by as much as a third the time and effort required to obtain an optimal strategy. 106 Chapter Six Use of the HCM This chapter describes the use of the HCM in an experimental situation, namely, searching for an optimal design for the road between Sapecho and Puerto Salinas in Bolivia (see figure 21.). The entire scope of activities associated with using the model--from data collection to design and engineering decisions--will be considered. Topics covered are data collection, i.e. what type of information is required, possible sources, and the required accuracy of this information, and the development of staging alternatives through the use of pruning rules and engineering judgment. Also discussed is the iterative search of the decision space with regard to the timing of investment and road design; maintenance policies ranging from poor labor intensive to excellent capital intensive maintenande; and the issue of uncertainty in traffic projections. 1. Data Collection The matter of data collection is perhaps the single most important area of interest in this section, as whatever results are obtained by the model are only as precise and useful as the data which has been used as input. The area where the most attention to accuracy should be given is the construction cost and the productivity 107 'I ! Map of Sapecho-Puerto Salinas Route Figure 21 108 data. This is because 1) on most low volume roads, con- struction costs are the major component of total road transportation costs, and 2) in the productivity data, errors frequently have the same bias--for example, consistently underestimating productivity--to a greater extent and significance than occurs with costs related to maintenance and user operating costs. The reason for this bias is that the required data will often come from one or two closely related sources and any error made in either source will thus be propagated. (In the remaining areas of data collection, however, there will almost always be a wide variety of sources, so that the possibility of offsetting errors is increased.) 2. Construction-Related Data There are three groups of construction-related data that are required by the HCM. They are: 1) site-dependent factors such as alignment, haul distances, and topographical information; 2) materials, labor, and equipment prices, which can often be considered fairly constant over a large area; and 3) design variables such as pavement cross sections, templates, and maximum and average grades. In the first stages of the design process, I feel that the greatest effort should be expended in determining the values of the second data set, as both the.first and third groups are much more easily manipulated by the model user. 109 It is a simple matter, for instance, to change a road cross section, but it is quite difficult to alter the productivity of labor or the unit costs of pavement construction. The prime source for construction-related data would be engineering feasiblity studies of roads in the same area, progress reports from construction projects in that region showing cost and resources consumed in performing a given amount of work, and summary figures for previous construction activity. Of course, the planner should be careful to establish that the figures used are not taken from a different type of construction organization from that which is expected to construct the road under question. For example, domestic and foreign constructors often operate at significantly different levels of performance and cost. Thus using the wrong data set would probably cause errors of considerable magnitude. The other construction-related data, especially the site-dependent factors such as alignment, horizontal curvature, haul distances, and terrain desriptions, can be roughly estimated at the early stages of work and given -in greater detail as more data becomes available. For instance, terrain properties can first be described by using contour line crossing densities and later be replaced by a one-point descriptor of the roadway center-line when details of the alignment are better known. The'tradeoff between costs of 110 data collection and accuracy of the answer cannot be explicitly stated; however, it is suggested that the best available maps be used during the design stages and that if the model is used during the final design stages, less than total reliance should be placed on earthwork volumes and costs since the one-point model, although inexpensive to use, is inaccurate when used on terrain having a non-zero side slope. Design variables can be specified in either of two ways: first, by letting the model specify the designs, or second, by explicitly specifying designs to replace those stored in the model. Unless there are extraordinary design re- quirements, i.e. very thick or thin pavement layers or narrow or wide lanes, it is often most convenient to let the model specify the designs for short cut analysis. 3. Maintenance-Related Data This class of data is often the easiest to collect, due to the small number of items that comprise it--maintenance policy, equipment rental rates, and material costs. The policy data can be supplied by the model or the user, and the per hour costs of equipment and men and the unit prices for materials can frequently be determined by reference to readily available sources within the maintenance division. In any case, since maintenance costs are usually only a small percentage of total costs, the total cost is 111 fairly insensitive to errors in these figures. Also, since costs are computed on the basis of resource consumption, errors in estimating the cost of maintenance will not affect the way in which the maintenance is performed. Thus it can be seen that the user should not devote extensive resources in determining these numbers during the preliminary design stages. 4. Data Related to User Operating Costs User operating -cost is a fairly sensitive area, as indicated by the research presented in the DOT report (57). The points .of greatest concern are the initial.costs of the vehicles and the per hour costs for the vehicle and its driver. Data derived from run #150, which was the base run for this analysis, showed that on a gravel road with a roughness of 512 inches per mile for commercial vehicles driver costs were between 11 and 23 percent of total market costs while vehicle expenses due to the initial cost of the equipment and tires was between 44 and 62 percent of total market costs. It must be recognized that these percentages vary with the road characteristics and, perhaps more importantly, with the user's definition of costs. The cost fig- ures that were used as input to the HOM were admittedly uncertain and it is unlikely that these would be the exact figures derived if completely accurate data was used. 112 How- ever, the use of other, more accurate, data (derived from the Argentine National Route 14 study) yielded similar results. Sources of information on user operating costs are likely to be readily available, but confusion may arise as to the distinction between market and economic costs as they are used by the model. "Market cost" refers to costs that are borne directly by the user, such as taxes, import duties, registration fees, purchase price, and similar items which will be paid for out of the user's pocket, while "economic cost" refers only to the cost to the economy, i.e. the price of the resources lost to the economy by the purchase and use of the vehicle and/or its accessories. The most important user operating costs are the initial prices of the vehicles and the gross weights of the vehicles (since these have significant effects on the deterioration of the road surface.) Figure 22 is a reproduction of the input data as echoed and annotated by the Highway Cost Model. By examining this illustration one may learn: the characteristics of the road alignment; the costs and productivities of construc.tion; the-normal maintenance policy; the topography along the road centerline; the California Bearing Ratio (CBR) of the subsoil; the percentage of the roadway that has heavy, normal, and light groundcover; some of the hydrological 113 C PAINTENANCE 0 USER 0 OUTPUT SWITCHES FOR THIS RUN ARE CCNSTRUCTION OUTPUT IS PRINTED FOR YEARS THAT ARE A MULTIPLE CF 20 UNLESS THIS NU912ER 1 IS POSITIVE INITIAL TRAFFIC CONhITIONS ASSOCIATED WIT7 3 SETS OF THE TRAFFIC GROWTH SWITCH IS -1 AND THERE ARE . THIS PRCJECT CATE 0/ 0/ 0 RUN 170 BOLIVIA TEST OF 25 YEAR ANALYSIS ALIGhNMENT DATA-ALIGN LENGTH UEG-CLRVE 6.10 15.00 PROfILIDATA- PPCF TYPE-SWITCH AVE-GRADE PAX-GRAOE NO-VPIS 9.29 15.00 -1.00 6.72 VPI STA VPI ELEX VPI STA VPI ELEV VPI STA VPI ELEV VPI STA VPI ELEV VPI STA V PI ELEV 7q0.00 1)13.00 835.C0 2100.00 0.0 896.00 140.00 886.00 600.00 9CC.U0 722.00 3660.00 702.00 3Q)0.010) 714.CC 4100.00 700.00 720.00 3140.00 d900.Oo 00.00 67C.00 4270.00 712.C00 460.00 680.00 4900.00 672.0C 55920.3 619.00 KUAAOuAD ••uSS SECTIONIHCRIZONTALI-TEPPL FILL-SL PAVE-hC WIDTH SLOPE SHLD-W0 SHLD-SL DTH-WO CTH-SL 'u4-wO 0TH-SL CUT-SL 1.50 4.50 2.00 1.CC 0.75 0.03 0.82 0.25 1.00 ROADWAY UctIGN DATA(VERTICAL)-PAVE THICK2 THICK SHLD-TPE THICKt THICK AOT-TPE MAT-TPE THICKNESS MAT-TPE PAVE-CD LAYERS 0.C 2.00 3.00 4.00 0.18 0.0 0.0 0.o O.C 2.00 0.18 ECONUMIC DATA •u OF PcrlOUS.DISC. RATE, NO OF VEHICLE TYPES 6.00 ? 20 FUrEIGN RATE CF EXCHANGE I PESU x 0.09330 DCLLARS PERCENTAtE OF COSTS THAT CRIGINATE FRCM FOREIGN SOURCES Pkl CENT OF VEFICLE COST * 80.00 PER CENT CF FUEL COST - 7T.0CFER CENT CF TIRE COST * 8C.0C PER CENT CF CONSTRUCTION EQUIPPENT COST 10CO.C0 Pca CENT CF LAeOR CCST * 43.00 PtK CENT OF SOURCE COST = 0.0 PER CENT OF MAINTENANCE EQUIPPENT COST - 1CO.CC MAINTENANN E POLICY-MAPGL MCW-FPR RUTFFL CRKOTH CRKFSLC MOW-SW BLAD-SW RLAD-ORY 8LAO-WET JuAIN-ýS RGRVLSW SHLD-SW 1.00 -1.00 O000.00 5000.00 3.00 0.80 C.50 0.50 I.ou 1.00 1.0C RtCALSThCTrICN SCHEDULE- RRLC NO-UPGKAu U TuPCGOAPHY- TOPOG 77 NU. CF STATICNS TTYPkClUt FLAT ROLLINr MCLNT NSTA 100.00 77.00 -1.uQ 0.0 0. ELEV. ELEV. STATION ELEV. STATION ELEV. STATION SIATICN cLEV. STATICN 893.00 896.CO 50.00 888.00 110.00 888.00 140.00 880.00 200.00 430.00 R01."0 'u.uO0 887.00 20.00C 896.00 350.00 400.00 898.CC 888.CC 710.0a 898.00 460.OU 900.00 490.00 895.00 550.00 908.00 630.00 920.00C 864.00 880.CC 740.0u 888.00 840.00 898.00 760.00 826.CC 860.00 82 .00 940*.4 870.CO 1C50.00 843.00 1130.00 868.00 1300.00 835.00 1520.00 802.00 2080.00 1630.UU 820.CO 1720.00 806.00 1860.00 816.C00 2030.00 795.00 765.00 786.0C 773.00 i210.00 79C.00 2280.00 2360.00 2150.00 790.00 210A.uU 719.03 740.00 2830.00 714.00 2900.00 714.CC 3060.00 782.CO 2610.90 704.00 714.00 3570.00 730.00 3300.00 3530.C00 710.00 314u.ud 722.00 3220.00 714.00 702.00 7C4.00 3870.00 716.CC 3900.00 36io.00 708.00 36e0.00 3770.0C 700.00 713.00 718.00 4070.00 688.00 4100.CC 4000.00 3930.uU 705.CO 3970.0C 4580.00 60C.00 696.00 4460.00 71C.CO 712.00 4270.00 712.00 4350.00 4430.00 666.00 665.00 4900.00 675.CC 5CO0.00 470.00C 4840.00 664.00 680G.00 682.00 5280.00 5400.00 SUOu50. 682.00 5120.0C 646.00 5200.00 658.00 631.CC 636.CC 5960.0C 67C.00 5790.00 5460.40 614.00 5520.00 623.00 5610.00 626.00 608G.00 674.00 61CO.0C 670.00 SLIL * 6RuUNCCOVEP-COER.0CCV CB0 EASY NCORAL CIFFICULT 6.uU 0.0 0.0 100.00 0.0 4.45 0.0 442U.U3 64C.00 Bolivian Base Scenario Data Figure 22 114 SIDE-CL 20.00 THICK3 0.C RUT-OTH 1.50 SUR ONT 0.0 DRAINAGE RcLATED CATA-CRAIN LT-RAIN WATR-BLUE IPPASS AVERAIN 1.00 40.00 &.00 1.00 IGO 01STANCESoCCkSTRUCT FLT-MEC 0.0 FLI-LCT C.0 HAUL I-BGR 10.00 HAULOIST LAYERI LAYER2 1.00 2.00 0.0 PAVEMENT LAVER3 SHCLLOER O.C 2.CO MPAITENANCE WATER 0.0 GRAVEL 2.CC PATrc 0.0 CULVERTS 200.00 WCNSTAUCTIuh PROCUCTIVITIES + COSTS-PRLO SITE PRIPAAATIOh *ASY O.u SURROW 0.u PAVEMENT PFau 448.00 0.0 NCRPAL 0.0 HARC 0.15 LCOST 127.20 EOCOST TRANSPORT P'OC LCOST EMCOST 0.0 110.00 1057.00 TRANSPORT LCOST 0.0 495.70 0.0 0.0 C.C 348.00 0.0 DRAANAGk NO. JF CULVERTS SCUST WEIGIT 384.uU 55.CC 52s.wU 825.00 SOURCE O.C * 0.0 0.0 0.0 0.0 0.0 4955.70 854.40 7464.00 EOCCST 3446.4C 0.0 0.0 3446.4C 5.00 TCOST 0.02 0.02 t71.UO 160.CO 0.02 AuGS.0o 210.C3 0.02 148..40 280.00 0.02 OIhkR CoMPjThENTS ICuaT 2LAOCR ITCTST ILABCK 0.0 0.0 0.0 MAINTINANLL COSTS ANC PRCCUCTIVITIES-MUC uCTORGO TRALuR DUMPTRK BIlklS 7?.C0 8s.tC 86.00 1SU.uu CLAbUk ELCPER FCREMAtI TCRIVER 13.4C 6.00O 6.uU 6.00 DIEb LFuPIL C.RCCST CAýCOST WA'ERC 0.0 ,.0 3.1 0.0 UStR WuSTS.kCON. AND MARKET- ECChCoMARK LAbs.A DRIVER GISCCST DIESEL 0.0 6.00 0.0 a.Q. 0.0 6..J 6.Co IhITIAL COST MARKET tCCjN.M 36U60.UU 54000.00 396G.W0 5760C.00 93*Lu.O, A44000.CO VE•ICLk OATA- VEI VE4TII UCWEILLL u.LUE U01 .84E C3 U.24& 01 u.27E C4 u*30E (a o.31E 04 3.0 04 TRACTOR 15.CC PATMIX C.0 WTRTRK 71.00 CJVSEAL 0.0 0.0 TIRE CC"T MARKET ECONCO 313.00 468.00 351.3C 576.00 1440.0' 2052.00 TCNWLS 0.45E 03 0.16E C4 0.20E RCLLER 77.5C LIQASIP 0.0 HRSEPMR 0.40E 02 0.14003 C.11E 03 VEPICLE MARKET ECONCP 9.7C 11.20 5.0C 9.40 26.10I 26.00 CARGO COST ECINCM MAkEtT 0.0 0.0 0.C 0.0 0.0 0.0 CHPVEHH VEPWCTI 0.10E 0! .T17E 01 J.20E Cl 0.139 01 0.15 11 J.24E 01 DSNSPEEC 0.12E 03 0.95E 02 O.50E 02 115 VEHHT 'IRCCEFF FUELTYPE 0.18E G& 0.TIE-O1 0.0 X.C 0.19k Cl C.24i-01 0.2SC Cl C.34E-01 0.n consideration the model needs to know; the haul distances for construction materials; maintenance unit costs; and vehicle descriptions and prices (among other factors). It sould also be noted that a road design is described under the headings ROADWAY CROSS SECTION and ROADWAY DESIGN DATA. This information is what the model must know before it can determine the costs of a road. 5. Development and Selection of Staging Alternatives This section discusses the problems involved in select- ing a set of strategies for investigation and how they can be "winnowed." from the large number of alternative designs and staging strategies that do exist. In order to reduce the number of designs which require examination, the problem is to distinguish within the continuum of all possible designs and staging strategies in such a way that 1) a representative number of alternatives is considered and 2) the number of alternatives examined is small enough so that undue amounts of time are not spent in computing their associated costs. The first parameter that can be used to narrow down the investigation is that of pavement design. There are four types of surfaces generally used for low volume roads --earth, gravel, surface treated, and bituminous or asphalt concrete. It is difficult to make meaningful distinctions between closely related road designs for the earth and 116 gravel roads while using the HCM, with the exception that regraveling will be required with less frequency on thicker gravel roads. However, regraveling has only a very slight effect on total road transport costs and can be disregarded during this discussion. Also, a surface treated road is a fairly well-defined design, with variations permitted only in the design of the base and sub-base. In contrast to the limited variations found in these designs, however, asphalt road designs can be found in far greater proliferation. There do exist design techniques that can be used (AASHO, RRL, Asphalt Institute, and local experience) to determine a starting point for the initial investigation. 6. Timing Timing of reconstruction is obviously one of the most important issues; the crucial question is: how sensitive are the total costs to small changes in the timing of reconstruction--for example, changing the reconstruction interval from every five to every six years. The HCM has demonstrated that for discount rates of twelve percent per year and less, if reconstruction is performed anywhere within a four- or five-year interval only small changes in total discounted construction, maintenance, and vehicle operating costs occur. For this reason a five-year interval for reconstruction is considered appropriate during the initial investigation of costs accruing to various strategies. 117 It should be noted that because of the iterative approach used in finding the optimal construction strategy, errors due to this somewhat arbitrary interval choice will be minimized. 7~ Upgradings This section will further delimit the alternate invest- gation space by defining feasible strategies for reconstrucThese strategies are based on the premise that the tion. model user will wish to improve the quality of a road in time, or to leave it alone (subject to considerations of de- terioration and maintenance.) Thus there are only a limited number of upgrading policies which can be implemented. For example, a gravel road can be upgraded to a surface treated or paved surface, but a paved road can only receive an overlay. Figure 9 shows the twenty-five feasible strategies that can be derived using this philosophy. An "S" as the last letter indicated new construction and is used in any but year one, or after the NULL option indicates an alignment change. The alignment change option should be explained in more detail. The model offers the option of changing the align- ment of the road during the design life. Thus a road con- structed with steep grades and sharp curvatures could be flattened out some years after the initial construction. Because of the great variety of situations in which this 118 type of reconstruction might be performed, it is difficult to generalize about a good choice for this option. However, as the pruning rules in the previous chapter indicate, reconstruction on a new alignment may be appropriate if some of the following conditions hold: the original road is on a very steep alignment; there is a narrow right-of-way with little room for expansion; traffic has grown at a high (ten percent or more) per'year rate and delays due to slow, heavy vehciles in the traffic stream are great; a suitable alternative alignment exists that does not unduly increase pointto-point distances. It is recognized that these conditions are not objectively defined and offer little practical guidance to the model user. Further research and use of the HOM in the field may yield sufficient experience to formalize these rules, which could then be incorporated into this work. However, since the model is inexpensive enough in actual use, such alternatives could be readily examined by the model' s users. 8. Maintenance Previous studies (Alexander and Moavenzadeh (36, 38)) have indicated the importance of maintenance in the operation of low volume roads. The role of maintenance is essentially to preserve the running surface and thereby reduce operating and reconstruction costs. The model offers the user the choice of six maintenance policies plus whatever he may 119 devise for himself. The results of several experiments with the HCM have indicated that under conditions of high labor prices the best policy in terms of total maintenance and user costs is normal capital intensive, while if the shadow price of foreign exchange is high, normal labor intensive appears to be the best policy. If it is desired that road users pay a greater proportion of road transport costs, then, of course, poor maintenance policies could be used; if it is desired that they pay a smaller proportion, excellent maintenance would be most appropriate. It should be noted, how- ever, that indications are that savings to the government due to poor maintenance policies are considerably less than the extra costs incurred by road users. This may not be true in contexts other than the Bolivia and Argentina scenarios, though, and the model user is urged to test this hypothesis by defining a staging strategy and examining the costs accruing to it when each of the six maintenance policies is used in conjunction with the staging strategy. In many cases he should find that total costs are lowest when normal or excellent maintenance is employed and that the savings due to poorer maintenance are overshadowed by increased-user operating costs and the need (in some cases) for earlier reconstruction. Assuming for the moment that there is no alternate 120 alignment suitable for examination, we are left with twenty-five alternate strategies suitable for investigation. This number can be further reduced by reference to the pruning rules of the previous chapter. For example,. assuming that initial traffic conditions are those presented in Ta-. ble 5 , the pruning rules indicate that earth roads, and any road that has an earth surface and is later upgraded, are undesirable. Thus, the number of alternatives to be investi- gated has been reduced by a factor of two, with corresponding reductions in direct computer costs. The utility of using the pruning rules and the consequent cost reductions must be traded off against the knowledge that these pruning rules have been based solely on two sets of factor prices and terrain data, and may very well be inaccurate under different conditions. Again, it is recommended that the user gain familiarity with the model and modify-those areas of the documentation that do not agree with his experience. 9. Search for the Optimal Road This section will discuss in some detail the procedure to be followed in using the Highway Cost Model to select an optimal road design within the limit of precision provided by the HOM. The reader should recognize that "optimal" is used in the context of a local optima, that is, within the decision space examined rather than a global optima which 121 vehicle class elasticity of demand vehicles/day ~~r~~r~~~~~ growth rate % per annum ~-----------------------~~ 15 .012 15 .003 30 .003 Traffic Data Used in Bolivian Base Scenario Table 5 122 would be the best of all possible roads. No techniques are known to exist that could find the latter. For the purposes of this examination, we shall continue to use the Bolivian data, along with the traffic projections and construction staging strategies already examined. It is expected that sufficient information will be presented to permit the reader to use the HCM effectively and accurately. The examination of the twenty-five alternate staging strategies makes up the first iteration of the model. Fig- ure 23 shows the total discounted costs accruing to each of these strategies and their relative rank. The timing of reconstruction can cause significant changes in cost. In order to investigate these effects, a second run was made. The strategies chosen for this run (see figure 24) were similar to the best strategies of the previous run (numbers 11, 14, 18, 19, 22) except that the timing of reconstruction for the staged alternatives was altered by +2 and -3 years respectively. The costs accruing to these strategies are given in figure 25. Ex- amination of these costs shows that the altered alternatives are more expensive than the original policies and should not be chosen for implementation. Since a change in timing has been shown to be ineffective in this case, the next issue to consider is the maintenance policy. The third iteration answers the question 123 25 24 9 S23 0 O O OO '-W Ir 0 C2 S22 U 6r 4.1 9 6 20 19 _1. Figure 23 Costs of the first iteration 124 _ GRAVEL2S SURFACES S -- ASPHALT ASPHALTS Year: I Staging Strategies for the Second Iteration Figure 24 125 Figure 25 210 200 190 Strategy Costs of the Second Iteration 126 "will excellent or poor maintenance policy decrease the costs accruing to these strategies?" This can be investigated by means of the input shown in figure 26. The numbers fol- lowing the design indicate the various maintenance policies, ranging from capital intensive to labor intensive and from poor to excellent. The figure shows the costs due to each of these maintenance strategies and indicates that an excellent capital intensive maintenance policy is the one to select if the measure of effectiveness is lowest net present worth. 10. Continuing the Iteration At this point the user should ask whether to continue the search process or to halt it. There are two criteria that can be used to make this decision. The first is-"are the expected costs of performing another run greater than the expected reductions in costs due to finding a better staging strategy?" The second is "do you feel that this strategy can be successfully implemented?" If the answer to either of these questions is "no", then the search pattern should be extended, another iteration performed, and the questions repeated. 11. Length of the Analysis Period The model user can choose this parameter on the basis of several factors--for example, institutional requirements 127 # 1 2 3 4 5 6 Strategy Definition Poor Capital Intensive Normal Capital Intensive Excellent Capital Intensive Poor labor intensive Normal Labor Intensive Excellent Labor Intensive 21.2 0 o 0 o o 021.o 4 .) 0 20.6 ... Mr --r ·- pl -- 40- 3 4 k--0 5 6 Strategy Figure 26 Costs of the Third Iteration 128 such as those of A.I.D. or the World Bank. The experience with the HCM indicates that the effect of varying the length of the analysis period is very much dependent on the context in which it is done. For example, extending the analysis horizon while examining gravel and asphalt roads will have different effects on the relative desirability of each, road depending upon the growth rates of each vehicle class, thme Iterest rate, the alignment (particularly the average grade), and the traffic level. Because of the multitude of factors involved in determining the effects of changes.in the analysis horizon, no recommendations as to the sensitivity to this parameter can be made. However, it is suggested that the model user, upon finding an optimal strategy, repeat the last iteration while varying the "nalysis period plus and minus five years to see the effect these changes have on the determination of the optimal strategy. 12. Effects of Uncertainty in Traffic Projections This section will discuss the effects of uncertain knowledge of future traffic levels on total costs, the distribution of costs among users, the road agency, and the optimal strategy for investment. Uncertainty in traffic projections as used in this report refers to the three factors used to describe traffic: 130 1) the number of vehicles in year one, 2) the elasticity of demand, and 3) the annual growth rate, either in terms of vehicles per year or percent per year. For low volume roads, and especially for penetration roads, most of these factors will not be definitely known. As variations from the estimates of these factors often occur in practice, and frequently cause the effectiveness of a road to be significantly diminished--a paved road, for example, being used by only thirty vehicles a day, or an earth road carrying one hundred seventy vehicles a day--it is desirable to decrease as far as possible the effects of uncertainty in the parameters. 13. Effects on Total Costs As expected, the factor which had the greatest effect on total costs was 'he growth rate. The reason for this is quite clearly the compound growth caused by constant percentage increases in traffic. For example, if the estimated yearly growth rate for one vehicle class is eight percent while in reality it turns out to be only six percent, then (assuming inelastic demand) after twenty years the total traffic will be overestimated by approximately twenty-five percent, while the number of vehicles using the road in year twenty will be seventy percent of the original estimate. Table. 6 , shows the costs and numbers of vehicles using the Bolivian road under these conditions. 131 It should be noted Vehicle Class IniT al a Traffic Vehicles in Year 20 G=6-7 G=8/ Ratio 1 15 48 70 0.7 2 15 48 70 0.7 3, 30 96 140 0.7 Effect of Inaccurate Growth Rates Table 6 132 Sthat although the total discounted road user costs have not shown a twenty-five percent change and while total costs are even less sensitive, there is a significant change in both categories. The second factor that Jis significant here is the elasticity of demand. Elasticity of demand is a measure of how sensitive the number of vehicles using the road is to changes in road user cost (for example, the cost reductions due to running on a paved rather than a gravel surface). In a sit- uation with very elastic demand, total traffic would be considerably greater on a paved road after twenty years than it would be on an earth or gravel road. crease is, ble (The relative in- of course, a function of the growth rate.) Ta- 7 shows the effects of different elasticities of demand on one class of ve.,icles for earth, gravel, and paved roads. In order to compare alternative strategies when the traffic demand function is elastic, the concept of willingness to pay was introduced. Appendix B presents a brief description of this concept and its use in strategy evaluation. Willingness to pay, as Appendix B shows, makes it possible to compare roads carrying different traffic volumes, since willingness to pay calculations involve determining a "base per kilometer cost" for each type of vehicle against which all operating costs are measured. If for a given road and vehicle type the per kilometer operating costs are lower 133 Road Type E=5% E=1.2% Ratio mm-m-m-m-mmmmm-mmm--mm-mmmmmmm------------------- Earth 19 20 Gravel 24 21 Paved 1.05 .88 30 22 .73 ----------------------------------------- Number of Vehicles in Year 20 for Two Demand Elasticities Table 7 134 than the base cost, the HOM subtracts the incremental willingness to pay from the total user costs. Similarly, if the per kilometer operating costs are higher the incremental willingness to pay is added to the user costs. The planner should recognize the necessity of using the same base strategy (and thus the same base costs) in all of his runs, or else he will introduce a bias into the succeeding iterations. 14. Initial Traffic Levels This variable is perhaps as difficult to estimate as any of the parameters discussed in this section, but fortunately its effects can be readily discerned. The realtionship between total road user costs and the initial number of vehicles is Uc = K i=1 aLNL where a and N refer to a given class of vehicles operating on a certain road type and maintained to a given standard. Thus, if-the initial estimate of traffic is doubled, user costs will also be doubled relative to the estimate. should be noted that this is It only true for similar construc- tion strategies, and that there will be a slight variation due to faster deterioration of the road when it is used by heavier traffic and to the increased maintenance costs on that road. 135 15. Effects on the Optimal Strategy As the previous discussion has indicated, uncertainty in the planner's knowledge of future traffic conditions can cause the estimated costs to differ significantly from the costs which occur in actual practice. Obviously such changes will affect the choice of optimal investment strategy under many conditions, assuming that road user costs are included in the measure of effectiveness used in evaluating competing costs. It is for this reason that the HOCM offers the user the option of specifying, during a single run, one or more sets of initial traffic conditions so that he may 1) estimate the probability of the realization of each set, 2) define the properties of each set: elasticity, growth rate, and initial traffic, and 3) see the costs accruing to each set and the expected value of the costs computed by the formula n E(C) = PiCi i=1 where Pi is the probability of realizing traffic set i, Ci is the costs accruing to set i, and n is the number of sets of traffic. Through this process the model user is given the opportunity to see how the optimal strategy varies with initial traffic properties. Once this information has been obtained, several procedures can be followed. 136 The simplest procedure is to build the.optimal road as defined using the expected costs determined from the equations presented above. Another approach would be to use that strategy which is optimal under the most likely (that is, having the highest probability of occurring) traffic set. A third procedure would be to select the strategy which has been ranked first more frequently than any other alternative. (If there is a tie for the greatest number of "firsts" then the one of these which also has the greatest number of "seconds" would be chosen, and so on.) In addition to these three selection procedures there are of course many other techniques; but it is recommended that the first approach be used for the following reasons: 1) In specifying the initial traffic sets and their probability of occurring, the user is attempting to describe a cont;iauous distribution of traffic using a small number of points. In so doing it is very unlikely that an accurate description has been made because of human error and the incomplete data that must be used in preparing estimates. 2) Over the long run, the use of the "expected cost" best strategy will have the highest benefits (this was established by Pratt at al. in Statistical Decision Theory (54)). 3) The choice of a strategy on the basis of other than the expected costs implies that the user has not accurately assessed his estimates of the probability of occurrence of the traffic sets; 137 by choosing a different strategy from the one found using expected costs he signifies that he does not believe his original assessment of the probabilities. 4) Assuming that the range of traffic conditions is not too great, a similar strategy will probably be optimal for many of the initial sets of traffic. Using this approach, the model user can expect that the optimal strategy will be cTlosely approximated by the road he has chosen for construction, even though it may not be identical to the optimal strategy under traffic conditions that do prevail. If the traffic that does materialize is considerably different from that which was expected, it may be worthwhile to use the model to estimate the costs which are incurred due to this new traffic and see how much the effectiveness of the link is reduced by the non-optimal design. If the reduction in effectiveness is considerable, it may be desirable to alter the design, either to the optimal design for the observed traffic level or to a design close to the optimal. 16. Road User Benefits During the previous discussion of the use of the HCM the concept of benefits has only been discussed in conjunction with incremental willingness to pay. It should not be assumed, however, that it is being suggested that 138 roads be constructed solely on the basis of perceived costs. It is recognized that benefits will accrue to the economy as a result of road construction--benefits which are important factors in the decision to build a road. This subject is not explicitly considered because of the difficulty in defining, measuring, and evaluating the benefits accruing to a road; the realization that these benefits are very much a function of the use of the road, the location, the products it carries, cannot be expressed as a formal model. To a limited extent, the incremental willingness to pay is a surrogate for these unmeasured benefits, and it is suggested that planners use the HCM in the early design process to seek out three or four construction strategies for further evaluation. The techniques presented here are designed for use at this stage of the design process; it cannot be emphasized too heavily that they should not be the basis of a final build-or-no-build decision. The HCM is a model with several well-defined areas requiring more research, and others requiring more sophistication. this reason, its estimates should be clearcut role as estimates. 139 For utilized only in a Chapter Seven Conclusion The Highway Cost Model can be a highly effective tool, providing fairly sophisticated planning for even the relatively inexperienced computer user. In the tradition of the "little black box", the model is able to perform this feat by internalizing its complexities. An example of the mcael's internalized complexity can be seen in the communications section of the program. This subroutine can take as input a list of the model user's staging strategies, which are written in a form close to conventional English; for example, the user would specify a two-lane earth road by writing "EARTH2S". This list would then be converted by the subroutine into a two-dimensional array which would then be utilized by the network routine to decide what actions NETWRK should take. ure 27 As fig- demonstrates, the communications subroutine can take a list of staging strategies such as the one shown in the top half of the figure and convert it into the array shown in the bottom half of the figure. The translation is accomplished by several hundred FORTRAN statements, which search a dictionary for the meaning of the user's commands and simultaneously keep track of the position of each of these commands in both time and space. STRAT can also, if necessary, redefine the dictionary; if local conditions (for 140 RECONSTRUCTION STRATEGIES 2.0 0. EARTH2S 0. 0.0 0. 0.0 0.0 .0. 0.0 0. 0. 0.0 0. 0.0 0.0 5. 0.0 5. 0.0 5. GRAVEL2S 0. 2.0 0.0 0. 0. 0.0 0.0 3. 0.0 0. 0.0 5., 5. 0.0 0. 2.0 SURFACES 0.0 0. 0. 0.0 5. 0.0 2.0 0. ASPHALTS 0.0 0. 0.0 0. 0.0 5. GRAVEL2 SURFACE ASPHALT ' SURFACE ASPHALT ASPHALT ASPFRNW RECGNSTRUC TION STRATEGIES TYPE MAINT. POLICY YEAR E 2.0000 1. 3. 2.0000 15. 9. 2 2.0000 3 15. 1C. 4 2.0000 15. 11. 2.0000 5 10. 9. 2.0000 10. 10. 2.0000 7 10. 11. S. 99. 2.0000 8 2.0000 5. 9 10. 5. 11. 2.0000 10 2.0000 1. 5. 11 15. i. 2.0000 12 2.0000 15. 11. i.1 2.0000 10. 10. 14 10. 2.0000 11. 15 2.0000 16 5. 10. 7 2.0000 5. 11. . 2.0000 1. 6. 15. 11. 2.0000 19 IC. 11. 2.0000 -1 2.0000 5. 11. 2.0000 1. 7. 22 2.0000 15. 12. 23 2.0000 24 10. 12. 0.0 5. 12. 25 NUMB EH YEAR OF NuDES STRATEGY 15 10 5 1 15 £1 11 15 10 5 .15 10 5 GRAVEL2 SURFACE ASPHALT SURFACE ASP-ALT ASPHALT ASPH RNW 0.0 0.0 0.0 0.0 2.0 2.0 2.0 0.0 0,0 0.0 0.0 0.0 0.0 2.0 2.0 0.0 0.0 0.0 0.0 2.0 0.0 0.0 0.0 2.0 0.0 0. 15. 15. 15. 0. 0. 0. 0. 0. 0. 0. 15. 0. 0. 0. 0. 0. 15. 0. 0, 0. 15. 0. 0. GRAVEL2 SURFACE ASPHALT SURFACE ASPHALT ASPHALT ASPHRIh STRATEGY 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. IS 13 BRANCHES 3 3 1. 10l 45 0. 0.0 0.0 0. 0.0 0. 0.0 0. 0.01 10. 0.0 10. 0.0 10. 2.0 0. 2.0 0. 2.0 0. 0,0 0. 0.0 0. 0.0 0. 0.0 10. 0.0 10. 2.0 0. 0. 2.0 0.0 0. 0. 0.0 0.0 10. 2.0 0. 0. 0.0 0.0 0. 0.0 10. 0.0 0. Ad 22 18 22 3 3 2 2 2 1 1 1 1 .Action of the Communication Subroutine 22 Figure 27 141 0.0 2.0 2.0 2.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.0 2.0 0.0 0.0 0.0 0.0 0.C 2.0 C.0 O.C 0.0 2.0 0.0 C.C example, very strong subsoils) exist, the model user can tell the model to remove certain road designs from the dictionary, and replace them with designs he feels are more appropriate. In addition to being simple, the model also makes allowances for the inexperienced user by being self-checking; if the model user specifies staging strategies incorrectly the model will bring a message to this effect, and will not execute the program at this time. types a card saying, "15GRAVEL2 respond by saying, "STRATEGY For example, if the user 10EARTH2S," the model will 1 IS SPECIFIED INCORRECTLY." But the model does not seek to eliminate the'user; on the contrary, it asks for his skill, knowledge, and experience as it searches for the best use can allocate his funds and energies. to which the planner For -xample, the model user is asked to define the staging strategies which he feels are appropriate to the road under consideration, and to evaluate each of these strategies. After evaluating this first iteration, he is then asked to alter the best strategies in a way that he feels will make them more effective; the model is thus at all times benefiting from the user's practical experience and his knowledge of the area, rather than merely seeking on its own some purely theoretical solution. The HCM is a modest program; it does not overreach its 142 own limitations or inflate its estimates into hard-and-fast predictions. This can be especially valuable in an uncer- tain situation. It is hoped that further implementation of the model (see Appendix A) will make it possible for the model to increase its precision without sacrificing its flexibility. In view of these advantages, it is suggested with some confidence that the HCM is an effective technique, which will be of service to planners in helping them to allocate scare resources to road projects, thus aiding in the optimal economic development of emerging nations. 143 REFERENCES 144 REFERENCES 1. Bauman, Richard D., An Analytical Method to Determine Highway Design and Forecast ' Stage Construction Levels 'in an Emerging Country, Ph.D. Thesis, Arizona State University, 1968. 2. Thompson, C.B., Transportation Coordination, Economic Section, Federal Public Works Department, Lagos, Nigeria, July 1959. 3. Bonney, R.S.P., The Relationships Between Road Building and Economic and Social Development in Sabah, Part I: Roads and Road Traffic, Lab. Note No. LN 519, Department of Scientific and Industrial Research, Road Research Laboratory, February 1964, 8. 4. A Guide to Highway Design Standards, International Bank for Reconstruction and Development, Washington, D.C. (June 1957) p. 69. 5. A Guide to the Structural Design of Bituminous-Surfaced Roads in Tropical and Sub-Tropical Countries, Road Research Laboratory, Road Note 31, London; HMSO, 2nd Edition, 1966. 6. Thickness Design, The Asphalt Institute, 8th Edition, December 1969. 7. Thrower, E.C., and Burt, M.E., A Study of the Economics of Stage Construction for Road Pavements, RRL Report LR 286, 1969. 8. Winfrey, Robley, "Cost Comparisons of Four-Lane vs. Stage Construction of Interstate Highway," HRBB #306, 1961, pp. 64. 9. Hewit, George G, "Asphalt Versus Gravel Roads in Developing Countries," World Highways, December 1969, Vol. 20, No. 12, p. 14. 10. Mori, Yasuo, "A Highway Investment Planning Model: An Application of Dynamic Programming", Unpublished M.S. Thesis, Department of Civil Engineering, M.I.T., Cambridge, Mass. 1968. 11. Stafford, Joseph H. and Richard de Neufville, Engineering Systems Analysis, Chapter 9: "Choosing Among Investment Alternatives," M.I.T., Cambridge, Mass., August 1970. 145 12. Marglin, Stephen A, Approaches to Dynamic Investment Planning, North Holland Publishing Co., Amsterdam, 1963. 13. Manne, Alan S., Editor,' Investments for Capacity Expansion, The M.I.T. Press, Cambridge, 1967. 14. Schezer, Herbert E., Analytibal Models for Managerial and Engineering Economics, Reinhold Publishing Corp., New York, 1964. 15. Haussmann, Fred, Operation Research Technique for Capital Investment, John Wiley & Sons, Inc., New York, 1968. 16. Ochoa-Rosso, Felipe, "Application of Discrete Optimization Techniques to Capital Investment and Network Synthesis Problems," Sc.D. Thesis, M.I.T., Cambridge, Mass. 17. Gulbrandsen, Odd, "Optimal Priority Rating of Resource Allocation by Dynamic Programming," Institute of Transport Economy, Royal Norwegian Council for Scientific, Industrial Research, Oslo. 18. Hillier, Frederick S., and Lieberman, Gerald J., Introduction to Operation Research, Holden-Day, Inc., San Francisco, 1967. 19. Winfrey, Robley, "Cost Comparison of Four-Lane vs. Stage Construction on Interstate Highways," Highway Research Board Bulletin No. 306, p. 64-80. 20. McKean, Roland N., Public Spending, McGraw-Hill Book Company, New York, 1968. 21. Hansmann, Fred, "Operation Research in National Planning of Underdeveloped Countries," Operations Research, Vol. 9, 1961, p. 230-244. 22. Reutlinger, Schlomo, Techniques for Project Appraised Under Uncertainty, World Bank Staff Occasional Papers, No. 10, IBRD, Washington, D.C., 1970. 23. Bierman, Harold, Jr., and Smidt, Seymour Smidt, The Capital Budgeting Decision, The MacMillan Company New York, 1966. 24. Dean, Joel, Capital Budgeting: Top Management Policy on Plant Equipment and Product Development, Columbia University Press, New York 1969. 146 25. Cord,J., "A Method for Allocating funds to Investment Projects Which are Subject to Uncertainty," Management Science 10, No. 2 235-241, Jan. 64. 26. Hansman,F., "Operations Research in National Planning of Underdeveloped Countries," OR 9, 230-248. 27. Nashlund, Biertel, and Whinston, "A Model of Multiperiod Investment Under Uncertainty," Management Science, Vol. 8 184-200, 1964. 28. Kalaba, R.E., and Juncora, "Optimal Design and Utilization of Communication Networks," Management Science, Vol. 3,33-44,1956. 29. Lorie, J. and Savage, "Three Problems in Capital Rationing," J. of Business, Vol 23, 57-71, Oct. 1955. 30. Hillier,F.S., "The Derivation of Probabilistic Information for the Evaluation of Risky Investments," Mgt. Science, Vol. 9, 443-457, 1963. 31. Raiffa,H., Preferences for Multi-Attributed Alternatives, Memorandum RM-5868-DOT/RC, The Rand Corp.., Santa Monica, April 1969. 32. Pecknold,W.,"The Evaluation of Transport Systems," Unpublished Ph. D. Thesis, M.I.T. Dept. of Civil Engineering, Sept. 1970. 33. Lack, G.N.T., et al, "A Model for the Economic Evaluation of Rural Road Investments," Paper No. 488, presented at the Fourth Conference of the Australian Road Research Board, Melbourne, August 1968. 34. Woods,K.B., editor, Highway Engineering Handbook, McGraw-Hill Book Co., Inc., New York, 1960. 35. Roberts, P.O.,"Transport Planning Models for Developing Countries," Ph. D. Thesis, Northwestern University, June 1966. 36. Alexander, J.A., "An Approach for Integrating Highway Maintenance Into the Design Process," Ph. D. Thesis, M.I.T. Dept. of Civil Engineering,.Sept. 1970. 37. Manheim, M.L. and Ruiter and Bhatt, Search and'Choice in Transport Systems Planning: Summary Report, M.I.T. Dept. of Civil Engineering Report #R68-40, 1968. 38. Moavenzadeh, F. et al., Highway Design Study: Final Report, CLM/Systems Inc., Cambridge, 1970. 147 39. Daniel, Mann, Johnson and Mendenhall et al., Bolivia Transport Survey, Los Angeles and La Paz, 1968. 40. U.N. Dept. of Economic and Social Affairs, " Capital Intensity and Costs in Earth Moving Operations," Bulletin No. 3, March 1960. 41. Shaner W,, Economic Evaluation of Investments in Agricultural 'Penetration Roads in Developing Countries: A Case Study of . The Tingo-Maria Tocada Project in Peru, Stanford Program on Engineering Economic Planning, Report Ee 22,August 1966. 42. Steiner, H.M., Criteria for Planning Rural Roads in a Developing Country: The Case of Mexico, Stanford Program on Engineering Economic Systems, Report Ee 17, August 1965. 43. Sen, A.K., Choice of Technique: An Aspect of the Theory of Planned Economic Development, Second Edition, New York, Kelley , 1965. 44. Harral, C., The Preparation and Evaluation of Transport Projects, WAshington, The Brookings Institute. 45. Midler, J.L., " Investment in Network Expansion Under Uncertainty," Transportation Research,Vol. 4, 267-280, 1970. 46. Burns, R.E., "Transport Planning: Selection of Analytical Techniques," J. of Transportation Economics, 306-321, Sept 1969. 47. Odier, L., The Economic Benefits of Road Construction and Improvement, Estoup, Paris,1967. 48. Haefele, E.T., editor, Transport and National Goals, Institution, Washington, D.C., 1969. 49. Raiffa, H.,Decision Analysis, Reading, Addison Wesley, 1968. 50. Lago, A.M. "Intercity Highway Transportation Cost Functions in Underdeveloped Countries," Ph. D. Thesis Harvard University, 1966. 51. de Weille, J., "Quantification of Road User Savings," I.B.R.;D., World Bank Staff Paper no. 2, Washington, D.C., 1966. 52. Soux, A.H., "Right-of-Way Preparation Cost," Unreleased study prepared by TRW Systems for the Office of High Speed Ground Transportation, U.S. Dept. of .Transportation, Contract C353-66 (Neg) 1968. 148 The Brookings 53. Charles River.Associates,. Inc,, Choice of Transport Technology Under Varying Factor Endowments in Less Developed Countries, Prepared for the Office of the Assistant Secretary for Policy and International Affairs, Dept. of Transportation, Washington, D.C., June 1970. 54. Pratt, J.W-, Raiffa, and Schlaifer, Introduction to Statistical Decision Theory, New York, McGraw Hill Book Co., 1965. 55. Midler, J.L., "Investment in Network Planning Under Uncertainty," Transportation Research, Vol 4, 267-280, 1970. 56. Pritsker, A.A.B., GERT, Graphical Evaluation and Review Technique, NASA Research Contract no..NASr-21, to the Rand Corp, Santa Monica, April 1966. 57. Moavenzadeh,F. et al., The Highway Cost Model, of Civil Engineering, Cambridge, March 1972. 58. Soberman, R.M., Transport Technology for Developing Regions, M.I.T. Press, Cambridge 1966. 59. Taylor, M.H., Network Planning in Management Control Systems, Hutchinson Educational Limited, London 1970. 60. Wagner,H.M., Principles of Englewood Cliffs, 1969. 61. Vance, L.M. Operations Research, M.I.T. Dept. Prentice-Hall, A Ro d Maintenance Cost Model, University of California , 1970. 62. Louis Berger, Inc., Argentina National Route 14 Technical Economic Feasibility Study, East Orange, N.J. 1968. 63. Baker-Wibberly and Associates, Inc., Puerto Salinas-Sapecho Highway Feasibility Study, Prepared for the Ministerio de Economica Nacional, Republic of Bolivia. 64. CLM Systems, Inc., I.B.R.D Economics Department working paper 96 Highway Design Study Phase I: The Model, Cambridge, 1971. 149 APPENDICES A. Recommendations for Further Work B. Willingness to Pay C. Argentina And Bolivia Data D. The Earthwork Models E. Listing of the Highway Cost Model 150 Appendix A Recommendations for Further Work Although the Highway Cost Model has been used extensively in analyses of Argentine and Bolivian road projects, it has not yet been used during the actual planning of a low-volume road in a developing nation. It is suggested that the HCM be used in the preliminary design stages of an appropriate road. Because it will be desirable to compare the effectiveness of the HCM with standard practices, perhaps the best approach would be to perform parallel analyses using both approaches. If, after the analysis is complete, significant variations are found to exist between.the solutions, it is recommended that the user reconsider carefully the assumptions which were made by the model and the engineering analyst who is using standard practice, and the planner should then attempt to reconcile the differences by modifying these assumptions where necessary. Additionally, the HCM could be modified to operate in an interactive model om a time sharing system. This com- paratively simple modification would make the planner an even more active force in seeking an optimal investment strategy and would probably decrease both the time and cost necessary to find the best strategy. If. field testing demonstrates that the HCM is useful in this context, it is recommended that further work be 151 performed to determine the accuracy of some of the more important relationships derived during the sensitivity analysis (DOT(57)), most particularly the relationship between velocity and road roughness. Also of importance is the problem of determining the culvert and drainage requirements and the relationship between frequency of blading unsurfaced roads and the observed roughness in inches per mile. 152 Appendix B Willingness to Pay* A short discussion of the supply and demand relationships of traffic will be used to explain the concept of willingness to pay and its use in strategy evaluation. The idealized demand curve shown in figure 28 as CD indicates the number of vehicles that will travel between two points as a function of the user's perceived price of travel. The supply curves for two strategies are labeled 1 and 2. These represent the perceived cost the user must pay (perceived user cost) as a-function of traffic volume for each strategy. For strategy 1, the supply and demand curves intersect at point E. Thus V1 vehicles use the road and each will have to pay the price P 1 in user costs. results in a total cost to users of (P 1 )(V 1 ). resented by the area GEHO in figure 28 . This This is rep- However, by defini- tion, the demand curve is a representation of willingness to pay. Most of the users in volume V 1 would have been willing to pay more than the actual price P 1. The last user to make up the volume V1 is represented in the demand curve at point E. 'He paid exactly what the trip was worth to him. *This material is appended courtesy of its author, John Alexander. 153 change in consumer surplus C r: change in willingness to pay GI. ?I , I i ,T~4A I .. -4 I strategy 1 '-tr tpo'v I """~~6~ I I I I -- 6 |. r:$ I - Vt V, Number of Vehicles Definition of Willingness to Pay Figure 28 154 ~D All the other users paid less than the trips were worth to them. The price they would have been willing to pay is represented by the portion of the demand curve between E and C. Presumably, the vehicle that wanted to use the road the most would have been willing to pay up to price Po. The difference between the total that users would have been willing to pay, CEHO, and what they actually paid, GEHO, is called consumer surplus, area CEG. Since this is a savings to the users of the system, it is usually considered a user benefit in economic analysis. If the same procedure is followed through for strategy 2, the user cost paid is represented by area FJOI, willingness to pay is area CFJO, and the consumer surplus is area CFI. When comparing alternative strategies, the analyst is interested in the differences in costs and benefits. In the example, strategy 2 can be considered to have a net user benefit relative to strategy 1 equal to the change in consumer surplus. in figure 28 . This is shown as the shaded area EFIG The change in consumer surplus is used as the measure of net road user benefit for this study. Change in consumer surplus, EFIG, is the difference between areas GEFJO and FJOI. FJOI represents road user cost paid for strategy i plus EFJH. the total Areas CE0O and CFJO have been shown to represent the total amounts 155 that users are willing to pay at prices PI and P 2 respectively. to pay, EFJH is thus called the change in total willingness when going from strategy 1 to strategy 2. There- fore change in consumer surplus between two alternative strategies is 0CSij or 'ACSij = UCi + WTPij - UCj = UCi - (UCj - WTPij) where ACSij = change in consumer surplus when changing from strategy i to strategy j UCi = total user cost for strategy i UCj = total user cost for strategy j AWTPij = change in willingness to pay when changing from strategy i to strategy j. As the previous section has suggested, the incremental willingness to pay increases in absolute value with increases in the elasticity of demand. As it can be considered a cost, it will affect the total costs of the road in question and make comparisons between alternate strategies slightly more complex and meaningful than they might otherwise be. For the Bolivian traffic data previously presented (see page HCM . ) Table 7 shows the costs as calculated by the By comparing the column labelled "Ratio" in both tables it can be seen that for both demand curves costs are proportional to the number of vehicles using the road for 1 56 any single road type. However, slight differences do exist and these are caused by the incremental willingness to pay being different for the two demand curves. (Alexander(36)) 157 Appendix C Argentina and Bolivia Data The following illustrations present a reproduction of the input data to the Highway Cost Model as echoed and annotated by the HCM of the base scenario for Argentina and Bolivia respectively. 158 MAINTENANCE OUTPUT SWITCHES FOR THIS RUN ARE CONSTRUCTION 0 0 USFr 0 OUTPUT IS PRINTED FOR YEARS THAT ARF A MULTIPLF OF 70 UNLESS THIS NUMRFP 1 IS POSITIVF INITIAL TRAFFIC CrNDITIONS ASSOCIATED WITH THIS THE TRAFFIC GROWTH SWITCH IS -1 AND THERE ARE 4 SETS OF RUN 159 GATF PROJECT 2/24/77 ARGENTINA DATA ALIGNMENT DATA-ALIGN LENGTH DEG-CURVE 20.00 0.10 PROFILE DATA- PRCF TYPE-SWITCH AVE-GRADE MAX-GRADE NO-VPIS -1.00 0.44 3.13 15.00 VPI STA VPI ELFV VPI STA VPI ELFV VPI STA VoE FL9V -TA VPI FLFV VPI STA VPI FLEV 52750.00 39.30 93900.00 32.30 9"st.0C 11.60 17020.*0 24.00 9200.00 T9.6R 59700.00 19.70 61000.00 21.4) 62710.CC 19.•6 21.40 64700.00 R.96 66900.00 10.07 6P450.OC 19.94 70900.00 10 .?! 11&R7I 7oEp 77900.00 25.90 ROADWAY CROSS SECTIONIHOPIaINTALI-TEMPL WIDTH SLOPE SHLD-WD SHLn-SL OTH-WO 0nT-S7I TH-1 TI-'L CUT-SL FILL-SL PAVF-WT 4.50 2.25 0.03 C.82 0.25 1.00 .3 1.CO 0.75 1.50 DESIGN DATA(VERTICAL)-PAVE THICK2 PAVE-CD LAYFRS MAT-TPE THICKNESS THICK THICK SHL50-TPF THTCKI 3.0 2.00 3.00 4.00 0.15 0.0 0.0 0.0 0.0 2.00 0.18 ECONIMIC OATA NO OF PERI.DS,0ISC. RATE, NO OF VEHICLE TYPFS 20 7.00 5 FOREIGN RATE CF EXCHANGE 1 PESOS . 0.00103 OCLLARS PERCENTAGE OF COSTS THAT C•pGINATE FROM 9RFIGN SrI5PCE. PER CENT OF VEHICLE CnST 8 0.'), EpEPC'T nF FUFL fOST - 70.PCPcP CENT OF TIrF CPST = 90.00 PFO CENT OF LARPR CCST . 0.0 PEP C9NT OF CONSTRUCTION FCUIIPMENT COST = 0o1.I 2..00 pOR CENT nF MAINTENANCE EOP)IPMENT COST = og.nn PER CKNT OF SURCF COST * MAINTENANCF POLICY-MAPnL n DRAIN-SW RPRVLSW SHtD-SW MOW-SW RLAT-SW SLA0-ORY RLA0-WFT UOW-FRO RUTFrt rPKnTH rRKCSL 1.00 1.00.0 000.00 9000.00 3.00 .eC 0.950 1.50 RECONSTRUCTION SCHEDULF- PFRL NO-UPGRAO VPI F411).00 ROADWAY 7,0 MAT-TPF MAT-TPE TOPOGRAPHY- TOFCG Nn. OF STATICNS 20 NSTA TYPECOOE FLAT RGLLING MOUNT 26.00 -1.00 100.00 0.0 0.1 STAT ION FLEV. ELFV. STATICN STAT ION STATION ELFV. STATION ELEV. FLFV. ;7250.00 '1.90 30.01 59000.00 52750.00 30.30 93900.00 6l,65. On 16.70 29.6 20.53 700a0.00 24.70 rQ701.00 29.90 58200.10 59600.00 57800.00 19.50 17.•0 60790.00 60500.00 19.00 '1000.00 272.6 61075.00 A son.o(' 21.60 0.00 69450.00 6or7l. O0 M.01) 65900.00 19.60 4 10OC.00 63600.00 70.57 716n. O00 0. O 70000.00oc 69500.00 15.90 70000.00 22.00 70400.00 728o0.00 29.60 SOIL * GRTUNDCCVER-CR9OGRCV T 01FFICUL CBR EASY NIPMAL 0.0 30.00C 7C.00 6.00 DRAINAGE RFLATFD OATA-nRAIN FLT-MEO FLT-LGT WATR-RLOE IMPASS AVERAIN 120.00 0.0 1.00 100 I nn 1.00 HAUL DISTANCESCCNSTRUTTICN PAVFMFNT MAINTFCANCF LAYFR3 SHnULEFR WATFR GRAVFL OATOH CtJLVFRTS X-BOR HAULDIST IATER1 LAYER2 147.00 40.00 0.0 390.00 10.00 3f.00 644.00 2.00 1'.0o CONSTRUCTICN PRCCUCTIVITIES + COSTS-PROD SITE PREPARATIC1 I Tn;T cornT0 HARE NORMAl EASY MT-RAIN 380.00 Argentine Base Scenario Data Figure 29 159 SITF-CL ?0.00 THICKR 0.0 RUJT-0TH 1.n S' *NT 1.0 0.20 20.36 0.50 0.40 EARTHWORK TRANSPORT BORROW PROD LCOST 1.26 0.06 250.00C 95.94 PAVFMENT PROD SOURCE TRANSPORT LCOST 400.00 1.86 0.00 67.52 0.01 163.00 22.30 96.23 387.00 65.70 0.0 151.61 163.00 22.30 0.01 96.23 DRAINAGE NO. OF CULVERTS = 3.00 SCOST WEIGHT Tr7OS 67.10 55.00 0.00 107.41 110.00 0.00 168.37 160.00 0.00 OTHER COMPONENTS XTCOST SLABOR YTCnST TLAPOP 0.0 0.0 0.0 0.0 MAINTENANCE COSTS ANO PPCOUCTIVITIES-MUC BITDIS DUMPTRK TRALDR MOTORG) 4.30 15.05 25.00 23.6, CLABOR ECOPER FOREMAN T0RIVFQ 2.65 5.80 6.70 4.8R DIESELFUEL GRCCST GASCOST WATERC 0.16 1.00 C.37 3.0 USER COSTSFCCN. AND MARKET- FCONn,MAPK LABORC DRIVER GASCOST OIES0 L 1.50 1.9q C.1R 0.15 3.00 .90q 0.37 0.16 TIRF COST INITIAL COST FCCNOM MARKET FCONIM MARKET 1C000.00 15000C.00 87.00 130.00 11000.00 160CC.00 q7.5C 160.on 26000.00 400C.00 400.00 r70.00 41rC.O0 63C000.00 Rg8.00 960.01 535.CC 790.00 79000.00 112rCC.00 VEHICLE OATA- VFF OFWEILLE VEHhT WTDPWLS HRSEP P 0.10E 01 0.10E C4 0.60E 03 0.45E 07 C.20E 01 0.30F 04 0.15E 04 3.10F 03 0.1OF 01 0.13E CS 0.50E 04 0.1IF 03 0.53F 01 0.24F nq 0.11E 05 0.12F 03 0.40E 01 0.50F 04 0.3CE 04 0.10E 33 63.40 EOCOST 417.34 EOCOST 147.20 207.77 451.16 207.77 ROLLER TRACYn wTRTPK PATwIX '7.25 rnvSFAL 1.00 q.68 L TOAHP 0.16 VEHICLe C1ST PCONCM 2.7C 1.40 7.23 7. oq 7.00 ')SNSPEFP 0n.5FC2 C.O9F 02 C.75F 02 C.6KF C2 0.79E 02 160 MARKFT 3.10 1.50 7.25 8.10 7.10 CARGO COST FCONOM MAPYFT 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0( 0.0 CHPVHH 0.0 0.0 0.10F 01 0.10F 01 0.10E 01 VrHWDTH VFHHT AIRCPFC C 1I 0.19E ri 0.20E CI 0.72E 01 0.17F-01 0.24F-01 O.23F 01 0.25F-01 0.27F-01 0.1PF 0.37F 01 0.?9F 01 n.24F 01 0.24E 01 0.16'F 01 0.27-rl FUEL TYPE 0. 3 ,3.0 0. , 0.10C 01 O.10 01 OUTPUT SWITCHES FOR THIS RUN ARE CCNSTRUCTION 0 PAINTENANCE 0 USA r. I IS POSITIVE OUTPUT 15 PRINTED FOR YEARS THAT ARE A MULTIPLE CF 20 UNLESS THIS INITIAL TRAFFIC CONOITIONS ASSOCIATED WITH THIS THE TRAFFI. GROWTH SbITCH IS -1 AND THERE ARE 3 SETS OF MU1MER , CATE O/ 0 RUN 170 PRCJECT 0 BULIVAA TkST OF 25 YEAR ANALYSIS ALIGNMENT DATA-ALIGN LENGTH uEG-CLRVE 6.10 15.00 PKOFILE DATA- PPCF TYPE-SkITCH AVE-GRADE MAX-GRADE NO-VPIS -1.00 6.72 9.29 15.00 VPt ELEV VPI STA VPI ELEV VPI STA VP! ELEV VPI STA VPI STA VPI ELEV VPI STA VPI ELEV 0.0 896.00 140.00 886.00 600.00 9Cc.ou 107).00 835.Co 2100.00 790.00 d900.uu 720.003 3140.00 722.00 3660.00 702.C0 319.09) 714.CC 4100.00 700.00 4270.00 712.00 4680.00 680.00 4900.00 672.0c0 5520.C 610.00 410O.00 67C.00 muADVAY ChuSS SECTONIhHCRIZONTALI-TEPPL WIDTH SLEPE SHLD-hD SHLD-SL DTH-hD CTH-SL :"-bO DTH-SL CUT-SL FILL-SL PAVE-hC SIDE-CL d.45 0.03 0.82 0.25 1.00 2.01, 3, i.CC C.75 1.50 4.!0 20.00 ROIAIWAY UOcIGN DATA(VERTICAL)-PAVE SHLC-TPE THICKJ THICK2 THICK3 PAVE-CU LAYERS MAT-TPE THICKNESS MAT-TPE THICK W*T-'PE THICK 2.u. 3.00 4.00 0.18 O.C 0.0 . .0 .C 2.CC 0.18 0.0 D.C ACONUMIC ,ATA hu OF PcARIQJS~OISC. RATE, NO OF VEmICLE TYPES 25 6.CO 3 FL~nixlu RATE CF EXCHANGE SPESu 0.09330 DCLLARS PEMCkNTAuE 3F COSTS ThAT CAIGINATE FPCM FOREIGN SCURCES PERR CENT CF FUEL CCST 80.00 P0a CENT CF VEFICLE COST 70.OCFER CENT CF TIME CCST * 80.0C PF. CENT CF LAFCR CCST * 43.00 PEIR CENT CF CONSTRUtCTION EQUIPMFNT CCST = IC0O.C PsK CENT OF SOURCE CCST 0O.0 PElR CENT OF MAINTENANCE EQUIPPENT CCST * ICO.CC MAINTENANL" POLICV-MAPCL MCW-FRQ RUTFFL CKCOTH CRKFSLC RUT-OTH RLAD-ORY BLAD-WET UiAIN-ad RGRVLSW SHLD-SW MOW-SW BLAD-S. 100O.C. 5000.00 3.00 0.80 C.50 0.50 1.50 1.0C 1.00 -1.00 L u* 1.00 kmC•iNSTkdJCICN SCFEDULE- RALC NU-UpfGatu TuPCGRAPHY- TOPOG 77 NO. CF STAfICNS NSTA TYPkCubU FLAT ROLLING MCONT 100.00 77.00 -l.uu 0.0 0.0 STATION SIATIC CLEV. STATICN ELEV. ELEV. STATION EL EV. STATION 880.CC 896.C0 50.00 881.00 110.00 888.00 140.00 200.00 430.00 80C.CC gSu.uO 887.00 20.00C 896.00 350.00 400.3C 848.CC 888.CC 46.0UU 900.00 490.00 895.00 550.00 908.00 630.00 710.CC 880.CC 74J.Ou 898.00 760.00 888.00 840.00 886.CC 860.00 920.00 94u.u, 870.00 IC50.0C 843.00 1130.00 668.00 1300.00 835.00 1520.00 2080.00 1630.uu 820.00 1720.00 806.00 1860.C0 816.CO 2030.00 795.CC 778.00 a210.00 790.00 2280.00 786.CC 2360.CC JAO.uU 790.00 2150.0C 714.CC 740.00 2830.00 714.00 2900.00 3060.C00 442u.u3 782.C0 2610.3C 714.00 3530.10 710.00 3570.00 314ueuj 722.00 3220.00 730.00 3300.00 7C4.00 3870.00 716.CC 3000.00 3770.OC 3640.00 738.00 3610.00 702.00 710.00 4000.00 718.00 4070.00 4100.CC 688.00. 3930.ijU 705.CO 3970.00 696.00 4460.00 71C.CC 4580.0C 4270.00 712.00 4350.0C 712.00 4430.00C 682.00 4840.00 665.00 4900.00 675.CC SCO0.0C 4770.00 664.00 *68Q0.B 646.00 5200.00 631.CC 5400.00 SIo0.uU 682.00 5120.00 658.00 5290.00 636.CC 5960.00C 5400.0O 614.00 5520.00 623.00 5610.00 626.C00 5790.00 *08G.UU 674.00 61W0.0C 670.00 SlL # bARuNCCOVEP-CER.GRqCV C8k EASY NCMRAL CIFFICULT S100.00 6.jU C.0 0.0 U.0 Bolivian Base Scenario Data Figure 30 161 6LTV. 893.00 891.~'0 849.00 864.00 823.00 802.00 765.03 719.03 704.00 714.00 7CO.C0 69C.00 666.00 60C.00 67C.00 PNT SUR 0.0 ORAINAGE RELATEC CATA-CRAIN IPPASS IVERAIN MATR-BLOE ,.00 1.00 40.00 HAUL GISTANCESCCKSTRUCTION PT-RAIN 1.00 g-8UR HAULDIST LAYER1 LAYER2 10.UO 1.00 2.00 0.0 CUNbTRUCTIAu PROCUCTIVITIES + COSTS-PROD SITE PRkPAKATICN EASY NCOPAL 4ARC LCOST O.u 0.0 0C.1. 127.20 ARIThw RK BOAROG TRANSPORT P'OC LCCST 0.0 0.0 825.00 1057.00 PAVEMENT FRGu SOURCE TRANSPORT ICOST j48.U0 0.0 0.0 495.70 0.0 0.0 0.0 0.0 k0. C.C 0.0 0.0 495.70 0.0 0.0 348.00 DRAINAGt 5.00 PO. . CULVERTS . SCUST WEIG-T TCOST 384.uU 55.00 0.02 52j.#. 110.CO 0.02 71..Uu 16C.C0 0.02 AUG5.uJ 210.C3 0.02 1486.,0 290.00 C.02 OThtR L.MPJNENTS SJ(I.z 2LAeCR 1TC'ST ILABCk U.u 0.0 0.0 0.0 MAINTENANIo COSTS ANC PRCCUCTIVITI ES-MUC 81T1b OUR FTRK TqALCR 7CT:RGD ". '.00 86.00 . 9 154.uu OLAb.jb EQCCER FCREAPn TCRIVER 6.uu 8.00 13.40 6.00 0IE~ELFULL GRCCST GCCOST wI'ERC 0.0 T.0 3.! 0.0 USeR LoST.tCON. AND 4ARKET- ECCKCMARK LAb.~A DRIVER GCSCCST DIESEL b.1J 6.00 0.0 0.0 6.40 6.CO 3.0 0.0 TIRE CCT IhlTIAL COST MARKET ECONTC MARKET LCCNJM 3bUo.UJ. 54000.00 313.00 468.00 39 5760C.00 351.30 576.00 93oto.UJ 1400.CU 4 1440.10 2052.00 VEHICLE JATA- VEF WTCQWLS HRSEPWR UcWEILLL VE1.T u.LUE 01 .. 84E 03 0.45E 03 0.410 02 u.2ýt Oi u.27E C4 T.16E C4 0.14E 03 u.30F Uo 0.31E 04 0.23E T4 0.11E 03 0b.k% FLT-MEC 0.0 FLT-LOT C.C PAVEMENT LAYER3 SHCLLDER 0.C 2.CO MAIkTEhANCE GRAVEL 2.CC WATER 0.0 PATC)0.0 CLLVERTS 200.00 EOCOST 854.40 ECCOST 7464.CC EQCCST 3446.4C 0.0 O.0 3446.4C RCLLER 77.5C LIQAS-P 0.0 TRACTOR 75.CC PAT7IX C.0 VEHICLE ECONCIP MARKET 9.7C 11.20 5.0c 5.40 26.10 26.00 DSNSPEEC 0.12E 03 0.45E 02 0.94E 02 162 WTRTRK 71.0C CJVSEAL 0.0 CARGO COST MAk, E 0.0 0.0 7.0 0.0 0.0 0.0 EC3NCM CHPVEHH 0.10E 0! 0.119 01 ).10E r1 VEHWCTF 01 J.20E Cl 0.24E 01 0.17E VEHHT AIRPCEFP 0.18E 01 C.17E-01 0.19E Cl C.24E-01 C.340-01 0.250 Cl FUELTYPF 0.0 .C ~.n Appendix D The Earthwork Models Earthwork costs are often the largest single construction cost component in low volume roads and they are often the hardest to estimate. A wide variety of earthwork estimating techniques exist and considerable development has gone into computer aided roadway design systems. These systems are of high accuracy but require large amounts of input data. This is in contrast to the requirements of the HCM which can accept less accuracy so long as the input requirements are also reduced. The earthwork models used in the HCM require as input the template and cross section of the pavement and either a series of stations taken along the centerline of the roadway or contour line densities which represent the rise and fall of the roadway. The one point model uses as input the series of stations of both the roadway and terrain alignment taken along the center-line of the road. It computes earth- work quantities taking into account pavement design and the horizontal template of the roadway using the average end area approach. In this case the end areas at a 1.6 3 terrain station are determined by summing the trapezoidal sections across the roadway. Suitable consideration is given to problems caused by transitions from cut to fill and the need to maintain grades. The contour line crossing density model was derived from work performed by Augusto Soux (52). This model estimates the earthwork volume required to bring a roadway alignment to grade as a function of the maximum allowable grade, road width, side slope, and the density of ten foot contours per mile. The data base was generated using a simple one point terrain model and utilized 84 separate roadway designs through a wide spectrum of terrain types. Road profiles were fitted to these terrain profiles and adjusted by trial and error to yield a minimum earthwork design, while at the same time retain a balance between cut and fill. The earthwork volumes were then plotted against contour density and curves were fitted to these data points with one for each maximum grade. The subroutine RFETH uses one set of the data developed and while it is properly sensitive to variations in design and topography the current version should be used with care.as limitations in the data base and the orientation of Souxls study to high design standard roads may cause some problems in transferring the results to low standard roads. (The material in this appendix appeared in a different form in Working Paper 96 of the International Bank for Reconstruction and Development It was prepared by Economics Department. Messrs. Moavenzadeh, Stafford, Suhrbier, and Alexander of CLM Systems, Inc. ( Consultants, Cambridge, Mass.) ( 64).). 1b5 Appendix E Listing of the Highway Cost Model The remainder of this appendix contains a listing of CONSTR. the routines MAIN, NETWRK, STRAT, SAVDAT, and These five routines make the cost estimating routines of the HCM a more effective and readily used tool for planners than it was initially. 166 C C MAIN PROGRAM OF THE HIGHWAY COST MODEL THIS SET OF COMPUTER PROGRAMS WAS DESIGNED AND UNDER DCT CONTRACT 05-00096 PROGRAMMED AT MIT INTEGER OU,OYRMOD,OTRACE,TPMF ,OSWTH(3) SUMD(12),OUTPT(12), TOT AL(12), DIMENSION SUM(12), FOREX(7), OUTFR(28), DOLAR(2), ,GROW(7), 1 OUTPD(12) 1 C 12 13 HCM HCM HCM HCM HCM 10 20 22 25 30 HCM 40) HCM HCM HCM ,TPMF,DISC,PNTPMF,IOIND COMMON/INOUT/IN,OU ,IRCON,OYRMOD,OTRACE HCM 1 , I ODVD HCM COfMMON/POLICY/ POL (30,20),COST(5,20) ,SAVE(20,170),RSTRT(30,4), HCM CONCOS(30,4), 1 NODE(30,3),NRECON,NNODE,NSTRT,DLSIGN(27,12), HCM 2 STRMPL(20,6) HCM ,TGROWS,GROW,SUM,SUM,TOTAL,TASK ( 1 2)HCM COMMON/RMBR/ BCCS(7),ECOS(7) HCM 1, GTTL,GTTLD,5STCST,CSTRT,OUTPT,OUTPO HCM 14CM COMMON STOR(963) HCM HCM STOR(961) ) EQUIVALENCE (OSWTH(1), HCM IN=5 HCM OU=6 HCM , IODVD REAO(IN,12) OSWTH,OYRMOD,OTRACE,TGROWS,TPMF,MORE HCM IF ( TPMF.EQ.O) TPMF=1 HCM IF( OYRMOD.EQ.0) OYRMOD=1 HCM WRITE(OU,13) OSWTH,OYRMOD,OTRACE,TGROWS,TPMF HCM CHECK OUTPUT FORM ( PER K CR TOTAL ROAD ) HCM IF( IODVD. NE.0)WRITE(OU, 14) HCM CALL PMIN HCM. CALL STRAT HCM CALL ERASE( CONCOS,120) HCM CALL NETWRK HCM IF(MORE.NE.0) GO TO 1 HCM CALL EXIT HCM ) FORMAT( 512,815 HCM CONSTRUCTION',13,' FORMAT('1 OUTPUT SWITCHES FOR THIS RUN ARE FMONY(3) I 50 60 70 80 83 86 87 90 100 110 120 130 140 150 160 170 180 100 200 210 220 230 240 250 260 270 280 290 300 310 14 00 1 MAINTENANCE',I3,' USER',13/' OUTPUT IS PRINTED FOR YEARS THATHCM 2 ARE A MULTIPLE OF',I3,' UNLESS THIS NUMBER',I3,' IS POSITIVE'/ HCM 3' THE TRAFFIC GROWTH SWITCH IS',T4,' AND THERE ARE',13,' SFTS OF HCM 4 INITIAL TRAFFIC CONDITIONS ASSOCIATED WITH THIS PROJECT ' ) HCM FORMAT('0 ***,,* ALL COSTS ARE FOR THE TOTAL LENGTH OF THE ROHCM iAD SECTION IN QUESTION ***** '/' -********PLEASE DISREGARD " PERHCM 2 KILOMETER " IN OUTPUT HEADINGS HCM END HCM 320 330 340 350 360 370 380 390 C C 71 SUBROUTINE NETWRK NET THIS PROGRAM CAUSES THE DECISION NETWORK TO BE STEPPED THRO UGH AS NET NET INTEGER OU, OYRMOD,'OTRACE,TGROWS ,ONVEH,OSWTH(3),RBLD( 11) ,TPMF, NET 1 RECON(25), STRT,YR,YR F,CCNST,YRICNT NET REAL INT, MAPrL(20.), HOTST(10), MARK(32) NET DIMENSION ALIGN(3),PROF(104) ,TEMPL(15),PAVE(1 2) ,ROUGH( 13), NET 1IEMAN(7,3),TRAF(7),ECO N(4),TOPOG(305),GOLGY(3) ,GRDCV(4), NET 2DRAIN(8 ),PROD(54), ECON 0(32),VEH(7,12) ,UT(150) ,WORK(40) , NET 3UXYZ(25) NET DIMENSION TRAFF(7,3), I OSWT( 3),SAVMPL(20) NET NFT COMMON/INOUT/IN,0OU ,IR CON,CYRMOD,OTRACE ,TPMF, DISC,PNTPMF, I OIND NET 1, IODVD NET COMMitON/POLICY/ POL (30, 20),COST(5,20),SAVE(20,170),RSTRT(30, 4), NET 1 NODE(30,3),NRECON,NNO DE,NSTRT, CESIGN(27,12), CONCOS(30,4), NET 2 STPMPL(20,6) NFT COMMON/RATEX/ FOREX 7) ,FMCNY(3),XRATE, OUTFR(2 8) ,OUTFRS(28 NET N COMMON/R;MiBR/ BCOS(7 ,ECOS(7), TGROWS,GROW(7),S UM(12),SUMD(1 2) , NET 1 TOT.AL(12),TASK(12) GTTL,GTTLD,STCST(30,8),CS TRT(30,8) ,OUT PT(12),NET 2 OUTPD(12) NET COMMON/PMBR2/ TRAFF2(7 ,3) NE T NET COMMON ALIGN,PROF,TEMPL,PAVE,ROUGH,OEMANTRAF,NPER,ECCN,MAPOL, NET 1RBLD,TOPOG,GOLGYCBR,GRDCV,DRAIN,HDIST,PRODUXYZ,ECONO,MARK,NUVEH, NET 2 VEH,OUT,WORK ,CSITH NET NET EQUIVAL. ENCE (TRAFF( 1, ), DEMAN(1,11)) ,(YRFNPER),(INTECON(1)), NE T Sf( OU,IPRNT ) NET DATA ICHBOD/5/ NET. NET AT FIRST ENTRANCE INTO NETWRK STORE USER SPECIFIED MAINTENANCE NET POLICIES IN SAVMPL NET DO 71 IK=1,20 NET SAVMPL(IK)= MAPOL(IK) NET WRITE(OU, 2018) NET 10 20 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 200 300 310. .320 330 340 350 360 370 380 C C 2012 IF(TPMF.EQ.1) GO TO 2001 NTPMF IS THE NTH SET OF INITIAL TRAFFIC CONDITIONS HAVING AN ASSOCIATED PROBABILITY CF CCCURRENCE PNTPMF NTPMF= TPMF CALL ERASE( STCST,240) STATEMENT 2012 IS THE STARTING POINT OF THE LOOP ASSOCIATED WITH UNCERTAINTY IN PREDICTIONS OF INITIAL TRAFFIC READ(IN,2013) PNTPMF WRITE(OU,2014) PNTPMF C 2001 C C C C C CONTINUE YR1CNT IS USED TO PERMIT THE USEP TO SUPPLY EMAND CURVES ONCE YR1CNT=-1 NNODE IS THE 4 OF NODES IN THE DECISION NETWORK NRECON IS THE # OF RECONSTRUCTIONS NSTRT IS THE # OF STAGING STRATEGIES STRT IS THE STRATEGY BEING EXAMINED SC START "C 0 INITIALIZATION OF VARIABLES CS=0. STRT=1 YR= 1 CONST IS A POINTER TO THE CONSTRUCTION ACTIVITY .BEING PERFORMED THE ARRAY POINTED AT IS RSTRT CONST =0 TOSWT(2)= OSWTH(2) IOSWT(3)= OSWTH(3) WORK(33) =0. WORK(35)=0. WORK(37)=0* INITIALIZATION CF ARRAYS C C INITIAL IZATION OF ARRAYS CALL ERASE ( TRAF,7,SUM,12,SUMD,12,0UTPT,12,0UTPD,12, 1 RECON,25) END VARIABLE INITIALIZATION TOTAL,12, NET NET NET NET NET NET NET NET NFT NET NET NET NET NET NET NET NET 390 400 410 420 430 440 450 460 470 480 490 500 510 520 530 540 550 N'13T 560 NET NFT NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET 570 580500 600 610 620 630 640 650 660 670. .680 690 700 710 720 730 740 C 931 DISC = 1./((1.+INT)**YR) IF(OTRACE.GT.O) GO TO 931 WRITE ( IPRNT,105 ) YR,DISC ,STRT CONTINUE IOIND=1 C S01 C 1 C -L12 13 C CHECK IF THIS RUN IS NOT SPECIFIED USING THE TREE STRUCTURE IF((NSTRT.EQ.0).AND.(YR.EQ.1)) GO TO 901 GO TO I IOP=O ENTER ROUTINE CONSTR AT ENTRY SIMCON FOR SI MPLE CONSTRUCTION CALL SINCCN(IOPI GO TO 9C11 CONTINUE IS THIS A NODE DO 12 I= 1,NNODE IF((NOD E(I,1).EQ.YR).AND.(NODE( I,2).EQ.STRT)) CONTINUE GO TO 14 CONTINUE I IS THE NODE # GO TO 13 IJ=I TYPE= 1 C 14 C 9 SAVE ROAD AND TRAFFIC PROPERTIES CALL SAVDAT (STRT,YR, IJTYPE) CONTINUE IS THIS (STRATEGY,YEAR) A RECONSTRUCTION PERIOD DO 9 1 =1,NRECON TRSI= RSTRT(I,1)+.01 IRS4= RSTRT(I,4)+.01 IF ((IRSI.EQ.YR).AND.(IRS4.EQ.STRT)) GO TO 10 CONTINUE NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NFT NET EFT NET NETNET NET NET NET NET NET NET NET NET NET. NET NET NET NET NET NET 750 760 770 780 790 800 810 820 830 840 850 860 870 880 890 900 910 920 930 940 950 960 970 980 990 1000 1010 1020 1030 1040 1050 1060 1070 1080 1090 1100 C C 10 C C 44 C C C C 7C 72 ", C 73 _Q 75 74 C C 11 112 C C 9011 C GO TO 112 I IS THE # OF THE RECONSTRUCTION CONST= CONST +1 CALL CONSTRUCTION COSTING ROUTINES CALL CONSTR(STRT,YR, I J,CCNST, ICHBOD) SELECTION OF MAINTENANCE POLICY TRANSFER USER SUPPLIED MNTPOL K=IJ IF( RSTPT(K,3).GE.O.1 ) GO TO 73 DO 72 IK=1,20 MAPOL(IK)= SAVMPL(IK) GO TO 74 TRANSFER PROGRAM SUPPLIED MNTPOL JKK= RSTRT(K,3) +.01 DO 75 IK=1,20 MAPOL(IK)= STRMPL(IK,JKK) IF(YR.FQ.1) GO TO 112 INDICATE TO MAINT THAT CCNSTRUCTION HAS OCCURRED RECCN(YR-1)= 1 CHECK IF PREVIOUS CONSTRUCTION WAS THE NULL ALTERNATIVE IF((CONST.FQ.1).nR.(RSTRT(CCNST-1 2).GT.1. )) GO TO 112 DO 11 IZ=1,NUVEH 00 11 IT=1,3 TRAFF(IZ,IT)= TRAFF2(IZ,IT) CONTINUE CHECK IF THE NULL ALTERNARIVE IS BEING EXAMINED IF(PSTRT(CO)NST,2).LE.1.1 ) GO TO 141 USE THIS SFCTIOON IF LINEAR STRATEGY SPECIFIED CONTINUE CALCULATIONS OF USER COSTS CALL USER (YR,YR1CNT) NET 1110 NET 1120 NET 1130 NET 1140 NET 1150 NET 1160 NET 1170 NET 1180 NET 1190 NET 1200 NET 1210 NET 1220 NET 1230 NET 1240 NET 1250 NET 1260 NFT 1270 NET 1280 NET 1290 NET 1300, NET 1310 NET 1320 NET 1330 NET 1340 NET 1350 NET 1360 NET 1370 NET 1380 NET 1390 NET. 1400 NET 1410 NET 1420 NET 1430 NET 1440 NET 1450 NET 1460 C 1341 1344 C HIF 1346 1345 1342 IF(YR.EQ.1) WRITE(OU,1029) YR,((TRAFF(IZIT),tl=1,w3),,OW(IZ), 1 IZ1,NUVEH ) CALCULATIONS OF MAINTENANCE CALL MAINT(YR,RECON) SUM MAINTENANCE AND OPERATING COSTS CHECK ON FORM OF OUTPUT DIVIS=ALI GN(1) IF( IODVD. NE.0) CIVIS=1. 00 1341 I=5,8 OUTPT(I) SOUT ( I+71)/rIVI S OUTPT(9) = OUT( 103) OUTPT(10) =OUT( 102) OUTPT( 11) =OUT( 1C4) OUTPT ( 12) =OUT (101) CHECK ON FORM OF OUTPUT ( IODV D.EQ.O) GO TO 1345 DO 1346 1 =9,12 OUTPT(I )= OUTPT ( I )* ALIGN( 1) DO 1342 I=5,12 OUTPO (I )=OUTPT( I)*DfISC SUM( I )=SUM(I)+ OUTPT(I) SUMD( I)= SUMO(I)+ OUTPD(I) TOTAL(5)= OUTPT(5)+ OUTPT(6)+ OUTPT(7) TOTAL(6)= OUTPD(5)+ OUTPD(6)+ OUTPO(7) TOTAL(7)= SUM(5)+ SIJM(6)+ SUM(7) TOTAL(8)= SUMD(5)+ SUMD(6)+ SUMO(7) TOTAL ( 11) =SUM(9 )SUM(10)(0 SUM(11)+SUM(12) TOTAL(12)=SUMD(9)+SUMD(10)+SUMD(11) +SUMD(12) TOTAL(9)=OUTPT(9)+OUTPT( 10 )+OUTPT(11)++UTPT(12) TOTAL(10)=OUTPD(9)+OUTPD(10) +OUTPD( 11)+OUTPD(12) GTTL= TCTAL(3) + TOTAL(7) + TOTAL(11) GTTLD= TOTAL(4) + TOTAL(8) + TOTAL(12) NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NE T NET NET NET NET NET NET NET NET NET NET NET NET NET 1470 1480 1490 1500 1510 1520 1530 1540 1550 1560 1570 1580 1590 1600 1610 1620 1630 1640 1650 1.660 1670 1680 1690 1700 1710 1720 1730 1740 1750 .1760 1770 1780 1790 1800 1810 1820 OTRACE.GT.0)) GO TO 504 IF ((YR.EQ.YRF).AND.( IF(OTRACE.GT.O) GO TO 932 IF( IOIND.LT. 0.5) GO TO 932 NET NET NET NET NET IF(OSWTH(2).LT.1) GO TO 1026 NET IF(IODVD.EQ.0) GO TO 1027 NET COMPUTE EFFORT REQUIRED FCR ENTIRE POADWAY C NET DO 2019 IK=1,12 NET 2019 TASK(IK)= TASK(IK)*ALIGN(1) NET WRITE(IPRNT,1028) TASK 1027 NET 1026 CONTINUE NET NET IF(OSWTH(3).LT.1) GO TO 504 NET C PRINT DETAILED USER OPERATING COST CATA NET 505 WRITE(IPRNT,5002) (OUT(I),I=105,146),(TRAF( I),1=1, 7) NET NET 504 CONTINUE WRITE(IPRNT,304 ) (OUTPT( I),CUTPO(I) ,SUM(I),SUMO(I) ,OUTPT(I+4) ,UTP 'NET ý,OUTPT(12) ,OUTPD( 12),SUM(12) ,SUMD'NET ID(I+4),SUM(I+4) ,SUMD(I+4),I=5,7) NET 1(12), (TOTAL(LL ),LL=5,12 ) NET 5033 CONTINUE NET 932 CONTINUE NET C NET FOREIGN COST FOR MAINTENANCE EQUIPMENT C NET IF(ECON(2) .GT. 0.) GO TO 621 NET OUTFR(17) =OUTPT(6)*FOREX(7) NET OUTFR(18)=OUTPD(6)*FOREX (7) NET OUTFR(1 9)=SUM(6 )*FOREX(7) NET OUTFR(20) =SUM0(6)*FOREX(7) NET C NET USED IN CPERATING MCDEL C FOREIGN CAPITAL NET WORK(33)=WORK(32) +WORK(33) NFT WORK(35)=WORK(34) +WORK(35) NET WORK(37)=WORK(36) +WORK(37) NET OUTFR(21)=WORK(32)FOREX( 1) +WORK(34)*FOREX(2)+WORK(36)*FOREX(3) NET OUTFR(22)=OUTFR(21 )*DISC 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 20202 2039 2040 2050 2060 2070 2080 2090 2100 2110 2120 2130 2140 2150 2160 2170 2180 C 333 OUTFR(23)=WORK(33)*FOREX(1)+WORK(35)*FOREX(2)+WORK(37)*FOREX(3) OUTFR (24)=OUTFR(23)*DISC TOTAL FOREIGN CAPITAL COSTS OUTFR(25)= OUTFR(17) +OUTFR(21) OUTFR(26) OUTFR(18) +OUTFR(22) OUTFP(27) =OUTFR(15)+OUTFR(19)+OUTFR(23) OUTFR(28)=OUTFR(16)+OUTFR( 2C)+OUTFR(24) IF(YR.EC.1) GO TO 333 GO TO 334 OUTFR(25) = OUTFR(25) + OUTFR(15) OUTFR(26) 334 = OUTFR(26) + CUTFR(16) CONTINUE COMPUTE COSTS IN DOLLARS 00 5034 I=17,28 5034 OUTFRS(I)= OUTFR (I)*XRATF IF ((YR.EQ.YRF).AND.( OTRACE.GT.0)) IF((OTRACE.GT.0).OR.( IOIND.LT. 0.5)) H -QC PRINT OUT FOREIGN COSTS Ln 5032 WRITE(IPRNT,600C) YR,FMONY ,(OUTFR( 621 IF((OTRACE.GT.O).OR.( IOIND.LT. 0.5)) C 933 C 141 ,C C C WRITE(IPRNT, 310) CONTINUE GO TO 5032 GO TO 933 I) ,I=17,28) GO TO 933 GTTL, GTTLD STEP TO NEXT TIME PERIOD CONTINUE YR= YR+1 CHECK FOR EN OF ANALYSIS IF( YR.GT.YR ) GO TO 714 DISC = 1./( +INT)**YR) THIS SECTION LIMITS OUTPUT TO YEARS ZERO MODULO MODK = MOD(Y R,OYRMOD IF(MODK.EQ. OSWTH(2)= 0 0) ) GO TO 704 INTM NET NET NET NET NET NET NET NET NET NET NET NET NET NFT NET NET NET NET NET NET NET NET NET NET NET NFT NET NET NET NET NET NET NET NET NET NET 2190 2200 2210 2220 2230 2240 2250 2251 2252 2253 2255 2257 2260 2270 2280 2290 2300 2310 2320 2330 2340 2350 2360 2370 2380 2390 2400 2410 2420 2430 2440 2450 2460 2470 2480 2490 704 706 934 OSWTH(3)= 0 IOIND =C GO TO 706 OSWTH(2)= IOSWT (2) OSWTH(3)= LOSWT(3) IOIND=l IF(OTRACE.LE.O) WRITE(OU,2018) CONTINUE IF((OTRACE.GT.0).OR.( ICIND.LT. 0.5)) GO TO 934 WRITE ( IPRNT,lC5 ) YR,DISC ,STRT CONTINUE IF( NSTRT.EQ.0O) GO TO 1 C C C H 714 i-J C C THIS STRATEGY HAS BEEN EXAMINED STORE THE COSTS DUE TO THIS STRATEGY IN ARRAY CSTRT CONTINUE INDICATE TO USER AND CONSTR THAT THE FIRST DEMAND CURVES HAVE BEEN READ AND THAT USER SHOULD NOT READ ANOTHER SET YR1CNT=YR CNT+2 YR=YR-1 WRITE(OU, 1029) 1 IZ=1,NUVEH ) CSTPT ( STRT, CSTRT ( STRT, CSTPT ( STRT, CSTRT ( STRT, CSTPT ( STRT, CSTRT ( STRT, CSTRT ( STRT, CSTRT ( STRT, C GO TO 9011 YR,(TRAFF(IZ,1),r)UT(IZ+125),TRAFF(IZ,3),GROW(IZ), 1) = 2) = 3) = 4) = 5)= 6)= 7)= 8) = TOTAL( 3) TOTAL( 7) TOTAL( 11) GTTL TOTAL( 4) TOTAL( 8) TOTAL( 12) GTTLO ZERO THE RECONSTRUCTION CALL ERASE ( RECON,25) ARRAY NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NFT 2500 2510 2520 2530 2540 2550 2560 2570 2580 2590 2600 2610 2620 2630 2640 2650 2660 2670 2680 2690 2700 2710 2720 2730. 2740 2750 2760 2770 2780 2790 2800 2810 2820 2830 2840 2850. C C C 421 IOIND=1 ARE ANY NODES ON THIS STRATEGY UNEXAMINED CONST= CONST+1 IF(CONST.GT.NRECON) GO TO 40 IF(NRECON.EQ.0) GO TO 40 YR= RSTRT(CCNST,1 ) Sl= RSTRT(CONST,4) IS1= Sl+.01 DISC = I./((1.+INT)**YR) WRITE(OU,1051) IS1,YRCISC LOCATE THE NODE TO BE RESTORED 00 42 K=1,NNOQE IF(NODE (K,2) .EQ. IS1) 42 423 GO TO 41 CONTINUE IS1=IS1-I GO TO 421 O C 41 411 CONTINUE Kl=K IF(NODE(K1,1).EQ.YR) GO TO 441 Kl= KI+1 IF ( K1.GT.NNODE) GO TO 423 GO TO 411 C 441 C C CONTINUE THE NODE # IS SET EQUAL TO Ki IF(NODE(K1,2).NE. IS1 ) GO TO 443 TYPE=-1 COMPUTE EXPECTED COSTS DUE TO UNCERTAINTY CALL SAVDAT(IS1,YR,K1,TYPE) STRT= 51+.01 GO 443 TO 44 WRITE(rUt,201) YR,S1 NET NET NET NET NET NET NET NET NET NET 2860 2870 2880 2890 2895 2900 2910 29?0 2930 2940 NET 2050 NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NET NEFT NET NET 2960 2970 2980 2990 3000 3010 3020 3030 3040 3050 3060 3070 3080. 3090 3100 3110 3120 3130 3140 3150 3160 3170 3180 3190 3200 NET NET --~ NET NET ( K, (POL(K1,K2),K2=1,16),CSTRT(KI,8),KI=1,NSTRT) NET NET IF( TPMF.EQ.1) RETJRN NET NET ' ' C COMPUTE EXPECTED COSTS DUE TO UNCERTAINTY IN TRAFFIC PROJECTIONS NET DO 2016 Kl= l,NSTRT NET NET DO 2016 K?= 1,8 NET 2C16 STCST(KI,K2) = STCST(K1,K2)+ PNTPMF*CSTRT(K1,K2) NTPMF= NTPMF-1 NET IF( NTPMF.GE.1) GO TO 2012 NET WRITE ( CU2017) NFT NET WRITE(OU,100) ( K,(STCST (K,J), J=1 ,8),K=1,NSTRT) ,KI=1,NSTRT) ,STCST(K1,8) K1,(POL(KI,K2K2=1,16) ( NET WRITE(OU, 1771) RETURN NET H NFT OD C FORMAT STATEMENTS NET 100 FORVAT('O COSTS FOR THIS RUN ARE '// NET 1 T30, ' UNDISCOUNTED ', NET T75,' DISCOUNTED ' / A ' STRATEGY',' CONSTRUCTION MAINTENANCE OPERATING TOTA L' I , NET 1 5X, 'CONSTRUCTION MAINTENANCE OPERATING TOTA L' NET B /R/ 15, 8F14.0 )) NET 105 FORMAT('0 YEAR',13,' DISCOUNT FACTOR',F7.3,' NET STRATEGY', 13) 201 FORMAT('0 ERROR IN RECONSTRUCTION LIST, CANNOT FIND RECONSTRUCT IONNET NFT STRATEGY ',FIO.0) I AT YEAR',IS,' $/ NET 304 FORMAT(lHOT30,'MAINTENANCE COSTS ($/KM)',T80,'OPERATING COSTS //T22,2 'T NET IKM)' NET 2HIS PERIOD',14X,'SUM TO OATE',8X)/T16,4('ACTUAL DISCOUNTED NET 3)/ S2.0/' MATERIAL' ,T12 ,8F12.0 NET EQUIPMENT',T12,8F 4' LABOR',T?2,8Fl2.0/' TOTAL' ,T12,8F12.0) NET 5/' INCREMENTAL WILLINGNESS TO PAY',T60,4FI2.0/' ACTUAL DISC NET FORMAT( 'OSUM OF ALL COSTS TO DATE($/KM) 310 NET I0UNTED '/T33,2Fl5.0 ) 40 RETURN CONTINUE IF( TPMF.GT.1) WRITE(OU,1 00)( WRITE(0U,1771) ITE(OUr2015) (CSTRT(KJ),J=1,8),K=1,NSTRT PNTPMF ) I 3210 3220 3230 3240 3250 3260 3270 3280 3290 3300 3310 3320 3330 3340 3350 3360 3370 3380 3390 3400 3410 3420 3430 3440. 3450 3460 3470 3480 3490 3500 3510 3520 3530 3540 3550 3560 1028 FORMAT( 'OPER KILOMETER MAINTENANCE COSTS BY TASK'/ I BLADE DRY NET 1 REGRAVEL ROADSIDE MOW DRAINAGE BLD WET PATCH CLDMIX HA NET HAUL A GGRGT PTCH RUT SEAL CRK '/8F12.0 / ' 2UL CLDMIX HAUL R NET 3UTPTCH SHOULDER '/ 7F12.0 ) NET 1029 FORMAT('0 TRAFFIC IN YEAR',15,' HAS THE FOLLOWING PROPERTIES NET ' VEHICLES /DAY BASE COST$/KM FLASTICITY GROWTH RATF'/ NET 2(T48, F5.0,3F15.3 )) NET 1051 FORMAT('1 START OF ANALYSIS FOR STRATEGY', I5,' IT IS YEAR',14,'0 NET I AND THE DISCOUNT FACTOR IS ', F7.3) NFT 1771 FOPMAT('O', T40,'STRATEGIES AND CGSTS'/ NET 1 ' STRATEGY DESCRIPTION' ,T0,'TOTAL DISCOUNTED COST'/ NET 2 (15,4(F5.0,2X,2A4,3X,F4.1),F 5 0 ) ) NET 2013 FORMAT(8F10.2) - NET FORMAT('1 THE ANALYST SPECIFIED PROBABILITY ASSOCIATED WITH THE NET I INITIAL TRAFFIC CONDITICNS IS',F10.4 / ) NET 2015 FORMAT('I THE USER SPECIFIED PROBABILITY ASSOCIATED WITH THESE NET 1 COSTS IS', F10.4 /) NET I-2017 FOPMAT('1 THE EXPECTED COSTS OF ALL STRATEGIES ARE AS FOLLOWS') NET `2018 FORMAT (1H1) NET 5002 FORMAT(1HO,' DETAILED OUTPUT FOR USER COST MODEL BROKEN DOWN BY VENET1HICLE TYPE PER VEHICLE KILCMETER'/ NET A ' LABOR HOURS',19X,7F10.3/' VELOCITY, KPH',17X,7F10.3/NET 2' FUEL CONSUMPTION, LITERS',6X,7FlO.3/f MARKET COST, DOLLARS', NET 310X, 7F10.3/' PARTS COST FACTOR PER 1000 KM',1X, 7F10.3/' INC.WILLNET 4. TO PAY ',5X, 7F10.3/' NUMBER OF VEHICLES',T30,7F10.1) NET 6000 FORMAT(//30X, ' FOREIGN EXCHANGE COSTS FOR YEAR ',1I2,' IN ',3A4,NET 1 ' ARE'/ T31,'THIS PERIOD',T60,'SUM TO DATE'/T26,'ACTUAL',T41, NET NET 2'DISC',T56,'ACTUAL',T71,'OISC'/ 3 ' MAINTENANCE TOTAL',T21,4FL5.1/' USER TOTAL',T21,4F15.1//NET 4' GRAND TOTAL',T21,4FI5.1) NET END NET 2014 3570 3580 3590 3600 3610 3620 3630 3640 3650 3660 3670 3680 3690 3700 3710 3720 3730 3740 3750 3760 3770 3780 3790 3800 3810 3820 3830 3840 3850 3860 3870 C SUBROUTINE STRAT THIS RCUTINE READS THE RECONSTRUCTION STAGING DATA INTEGER OU,OYRMOD,OTRACE,TGROWS ,DNVEH,OSWTH(3),RBLD(11) TPMF DIMENSION ALPHA(11,2) DIMENSION RSTRT (30,4), NODE(30,3),POL(30,20),COST(5,20), 1 SAVE(20,170), DES.IGN(27,12) COMMON/INOUT/IN,CU ,IRCON,OYRMOD,OTRACE ,TPMF, DISCPNTPMF, IO IND COMMON/POLICY/ POL,COST,SAVE,RSTRT,NODE,NRECON,NNODE,NSTRT ,D ESIGN I 1 , CONCCS(30,4) COfYMON/YRCOST/YRCS (5) EQUI VAt. ENCE EQUIVALENCE I PRNT, OU) NSTRAT,NSTRT) STRA STRA STRA STRA STRA STRA STRA STR.A STRA STRA STRA STRA STRA STRA STRA STRA STRA ST R A NNODE=# OF NODES NRECON IS THE # OF CONSTRUCTION PERIODS NSTRT IS THENUMBER OF STAGING STRATEGIES DATA Al PHA /'NUll '.'FART'.'FART'.'rRAV'.~'GRA V','SURF,'LASPH' STRA 1 'EART','GRAV',i'SJRF','ASPH ' ' ','HIS ' ,'H2S ','ELS',' EL2S' , STRA 2 'ACES','ALTS','K2 ','EL2 ','ACE ','ALT ' / STPA C NALPH IS # OF ROAD DESIGNS DATA 15 351 C IN STORAGE NALPH/12/ YRCS(1)=-l READ(IN,15) NSTRAT,NEXDS,IDESSW FORMAT(I110) WPITE(OU,351) NSTRT,NEXDS FORMAT('1 THE NUMBER OF RECONSTRUCTION STRAT EGIES 2E NUMBER OF COST SETS IS ',I5 ) NSTRT IS THE NUMBIER OF STAGING STRATEGIES NRECCN = 0 IF C C (NSTRAT.EO.0) GO TO 199 INITIALIZE ARRAYS CALL ERASE( RSTRT,120,POL,600,NODE,90 ) IS', 15,' STRA STRA STRA STRA STRA STRA AND THSTRA STRA STRA STRA STRA STRA STRA STRA STRA 10 20 50 60 70 80 90 100 110 120 130 140 150 160 170 190 200 210 220 230 240 250 260 270 280 290 300 310 320 325 330 340 350 360 370 C CHECK IF NEW DESIGN IS DESIRED IF( IDESSW.EQ.O) GI0 TO 84 DO 82 IZ=1,IDESSW READ(IN,15) ID WRITE(OU,83) ID READ (IN,80) AL PHA(ID,1 ALPHA( ID,2) WRITE(OU,81) AL PHA(ID,1 ALPHA(IO1,2) READ(IN,831) ( DESIGN( ID),1I=1 11)) READ(IN,831) ( DESIGN( ID),I=16,27) WRITE(OU ,802) WRITE(OU,830) ( DFSIGN(I,ID),I=1,11) WRITE (OU,803) WRITE(OU,830) ( DESIGN( I,ID),I=16,27) CONTINUE WRITE(OU,174 ) DO 175 I =1, NSTRAT READ (IN,176) WRITE(OU,177) 175 178 180 (POL(IJ),J=1,16 ( ) POL(IJ),J=1,16 ) CONTINUE N=O IF( NEXDS.LE.0) GO TO 180 N=N+1 READ(IN,179) YRCS(N) WRITE(OU,1792) YRCS(N) READ(INi,179) ( COST(N,J),J=1,20 NEXDS= NEXDS-1 GO TO 178 CONTINUE THIS SECTION TRANSLATES INPUT THE REMAINING SUBROUTINES NRECON=0O N=NRECON INITIALIZE COUNTERS ) INTO A FORM THAT CAN BE USED BY STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA STR A STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA STR A STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA STRA 380 390 400 410 420 430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 580 590 600 610. 620 630 640 650 660 670 680 690 700 710 720 730 150 151 C C C C C 155 C C C C 1521 J=O J=J+l J4=-3 !F(J.GT.NSTRT) GO TO 190 J4=J4+4 - !F(J4.GT.17) GO TO 150 TEST FOR DESIRED RECONSTRUCTION IF( POL(J,J4).EQ.0) GO TO 151 FIND PROPERTIES OF THIS RECONSTRUCTION INCREMENT RECONSTRUCTION COUNTER NRECON= NRECON+l N= NRECCN YEAR = PCL(J,J4) RSTRT(N,1) RECCNSTRUCTION TYPE 1=0 IF( I.G E.NALPH) GO TO 152 I=1 +1 GO TO 155 IF( POL (J,J4+2) .NE.ALPHA(1,2)) RSTRT(N ,2) =1 MAINTENANCE POLICY RSTRT(N,3)= POL(J,J4+3) STRATEGY RSTRT(N,4)= J GO TO 151 ERROR IN INPUT DATA WRITE(OU,153) J1 CALL EXIT 152 WPITE(OU, 153) J CALL EXIT C 190 WRITE ARRAY RSTRT ON PRINTER WRITE(OU,191) ( I,(RSTRT(I,J),J=1,4),I=1,NRECON) WRITE(OU,192) STRA 740 STRA 750 STRA 760 STRA 770 STRA 780 STRA 790 STRA 800 STRA 810 STRA 820 STRA 830 STRA 840 STRA 850 STRA 860 STRA 870 STRA 880 STRA 890 STRA 900 STRA 910 STRA 920 STRA 930 STRA 932 STRA 936 STRA 940 STRA 950 STRA 960 STRA 970 STRA 980 STRA 990 STRA100O STRA1010 STRA1020 STRA1030 STRA OLO4 STRA1050 STRA1060 STRA1070 C C C C C THIS SECTION LOCATES NODES IN THE DECISION NETWORK NODES ARE POINTS WHERE TWO OR MCRE ALTERNATIVES EXIST I IS THE NODE NUMBER THE SUBSCRIPT J REFERS TO STRATEGIES IF ( NSTRAT.EQ,O) GO TO 199 NODYR1=-1 197 C 115 C I=0 J=1. J4=-3 J=J+l IF ( J.GT.NSTRAT ) G 0 TO 194 LOCATE BRANCHES J4=J4+4 IF ( POL(J,J4).EQ.0) GO TO 195 LABFL NCDES I=1+1 INiOIJ 196 191 198 C 203 205 I L = ruLIJ, J+ IF ( NODE(I,1).FQ.1 ) GO TO 207 LOCATE MAIN BRANCH J1=J J1=J1-1 IF(JI.EO.0) GO TO 1521 J14=J4 J14= J14-4 IF (J14.LT.1) GO TO 196 GO TO 1981 IF(POL(Jl,J14).EQ.O.) NODE (1,2)=Jl NODE(I,3)= NODE(I,3)+1 CHECK IF THIS NODE HAS BEEN PREVIOUSLY IDENTIFIED 11= I-1 IF(II.EC.0) GO TO 197 IF( NODE(I,1).EQ.NODE(II,1)) GO TO 205 GO TO 197 IF( NODE(I,2).EQ.NODE(I1,2)) GO TO 204 GO TO 197 STRA1080 STRA1090 STRA1100 STRA1110 STRA1120 STRA1139 STRAl149 STRA 150 STRA1160 STRAI170 STRA1180 STRA119O STRAI200 STRA1210 STRAI220 STRA1230 STR41240 S'TRA 1250 STRA1260 STRA1270 STRA1280 STRA 290 STRA1300 STRA1310 STRA1323 STRA1330 STRA1340 STRA1350 STRA1360 STRA1370 STRA1380 STRA1390 STRA1400 STRA1410 STRA1420 STRA1430 C 204 C C 207 C C C 209 208 C C C C 194 UPDATE NUMBER OF BRANCHES FROM NODES I , I-1I NODE(I,3)= NODE(T,3)-1 NODE(11,3)= NODE(Il13) +1 RESET NCDE COUNTER 1=11 GO TO 197 THIS SECTION IS USFD WHEN A STRATEGY IS SPECIFIED CONTINUF IF (NODYR1.LT.O) GO TO 209 A BRANCH FROM YEAR 1 HAS BEEN FOUND PREVIOUSLY NODE(KNOYR1,3)= NODE( KNOYRI,3) +1 DECREASE NODE CCUNTER 1=I-1I GO TO 197 THIS IS FOR FIRST BRANCH FRCM YEAR 1 KI=J KI=Kl-1 IF(POL(Ki,1).EQ.O ) GO TO 208 NODE(I,2)= KI NODE(T,3)=NODE( 1,3)+1 KNf]YRI =I NODYR1=1 GO TO 197 WRITE OUTPUT IN YEAR DATA NNODE IS THE NUMB ER OF NODES IN THE DECISION NETWORK NNODE=I WPITE(OU,200) I,( (NODE(J K),K=1,3),J=l, I) 202 RFTURN 199 WRITE(OU,193) RETURN C FORMAT STATEMENTS C FORMAT(2A4) 8C STRA1440 STRA1450 STRA1460 STRA1470 STRA1480 STRA1490 STRA1500 STRA1510 STRAI520 STRA1530 STRA1540 STRA1550 STRA1560 STRA1570 STRA1580 STRA1590 STRA1600 STR A 1610 STRA1620 STRA1630 STRA1640 STRA1650 STRA1660 STRA1670 STRA1680 STRA1690 STRA1700 STRA1710 STRA1720 STRA1730 STRA1740 STRA1750 STRA1760 STRA1770 STRA1780 STRA17O0 IT HAS THE FOLLOSTRA1800 FORMAT(' THE USER SPECIFIED DESIGN IS ',2A4 / ' STRA1810 IWING CHARACTERISTICS ' ) 83 FORMAT (' DATA FOR USER SPECIFIED DESIG N #',15) STRA1820 153 FORMAT(' RECONSTRUCTION STRATEGY ', 14 , IS IMPROPERLY SPECIFIED'STRA8I30 STRA1840 1 ) 174 FORMAT( 'ORFCONSTRUCTION STRATEGIES ') STRA1850 5(F2.0,2A4,2X,F3.0 )) STRA1860 176 FORMAT( F5.C0,2X,2A4,3X,F4.1 )) 177 FOPMAT (' t,5( STRA1870 179 FORMAT( (5F10.2 )) STRA 1880 191 FORMAT( '0 RECONSTRUCTION STRATFGIFS'/' YEAR TYPE STRA1890 STRATEGY ' ) STRAl900 1 MAINT. POLICY )) STRA1910 1~2 FORMAT( (18,2FlO.O,FIO.4,FL0IO t 193 FORMAT( '0 NJ RECONSTRUCTION THIS RUN E ) STRAl920 200 FORMAT( 'ONUMBER OF NODES IS ',13 /(' STRATEGY BRANCHES')/ STRA1930 YE AR STRA194O 1 (( 14,19, 19,3X ))) 802 FORMAT(' WIDTH SLOPE SHLD-WD SHLD-SL DTH-WD DTHSTRA1950 FILL-SL PAVE-WD SIDE-CL') STRA1960 1-SL DTH-WD OTH-SL CUT-SL MAT-TPE THI STRA1970 LAYERS MAT-TPE THICKNESS 0)3 FUt' R I % -•V -,L)V STRA19PO THICK2 THICK3') SHLD-TPE THICKI THICK MAT-TPE ICK STRA190Q 830 FORMAT(12FI0.2) STRA2000 FORMAT(8F10.2) 831 FORMAT('O THESE COSTS ARE FOR YEAR',F10.0) 1792 STRA2010 END STRA2020 81 C C C SAV SUBROUTINE SAVDAT (STRT,YR,IJ,TYPE) THIS PROGRAM STORES AND RESTORES ROAD AND TRAFFI CONDITIONS AT NODSAV INTEGER STRT,YROUT SAV DIMENSION RSTRT (30,4), NODE(30,3),POL(30,?O),COST(5,20), SAV 1 SAVE(20,170), DESIGN(27,12) SAV COMMON/POLICY/ POL,COST,SAVE,RSTRT,NCDE,NRECON,NNODE,NSTRT,DESIGN SAV 10 20 30 40 50 60 1 SAV 70 SAV SAV SAV SAV SAV 80 90 100 110 120 SAV 130 SAV SAV SAV SAV S-AV SAV SAVSAV SAV SAV SAV SAV SAV SAV SAV SAV SAV. SAV SAV SAV SAV SAV SAV 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 320 330 340 350 360 , IF C C I 11 HC 10 C 9 C C 3 111 101 92 2 C CONCOS(30,4) COMMON STOR(963) COMMON/PMPBR/STOR2 (58) COMMON/INOUT/ IN,OUT IF TYPE IS NEGATIVE THIS IS A RESTORE IF TYPE IS POSITIVE THIS IS A SA':E (TYPE ) 1,2,3 RESTORE ROAD CONDITIONS PAVFMENT TEMPLATE AND TRAFFIC LEVELS DO 11 I=1,67 STOR(107+I)= SAVE(IJ,I) PRODUCTIVITY 00 10 I=68,107 STOR(920+I-67)= SAVE(IJvI) TRAFFIC DEMAND AND ELASTICITY DO 9 1= 108,165 STOR2(I-107)= SAVE(IJrI) WRITE(CUT,12) STRT,YR,IJ RETURN SAVE ROAD CONDTIONS DO 111 I=1,67 SAVE(IJ,I)= STOR(107+I) DO 101 1=68,107 SAVE(IJ,I)= STOR (920+1-67 ) DO 92 I=108,165 SAVE( IJ, I)= STOR2 (1-107) WRITE(OUT,31) STRT,YR,t IJ RETURN - C 12 31 FORMAT STATEMENTS FORMAT('O ROAD AND TRAFFIC CONDTICNS I' STRATEGY ',13,' YEARP',3,' NODE FORMAT('OROAO AND TRAFFIC CCNDITIONS 1' STRATEGY ',13,' YEAR',I3,' NODE END HAVE BEEN RESTORED', NUMBER ',t3 ) HAVE BEFEN SAVED 'I NUMBER ',13 ) SAV SAV SAV SAV SAV SAV 370 380 390 400 410 420 CON CON CON .CON CON CON CON CON CON CON CON CON CON CON CON COMMON/ INOUT/IN,nu , IRCON,OYRMOD,OTRACE ,TPMF,DISC,PNTPMF,IOIND CON CON I ,IOVD COMMOF)N/ POLICY/ POL(30,201),CCST(5,20),SAVE(20,170),RSTRT(30,4), CON 1 NODE(3 0,3),NRECON,NNODE,NSTRT,CESIGN(27,12), CONCOS(30,4), CON CON 2 STPMPL (20,6) COMMON/ RATEX/ FOREX(7),FMONY(3),XRATE, CON OUTFR(28) ,OUTFRS(28) COMMON/ FMBRP/ CON BCOS(7),ECOS(7), TGROWS,GROW(7),SUM(12),SUMD(12), 1 TOTAL( 12),TASK(12), GTTL,GTTLD,STCST(30,8),CSTRT(30,8),OUTPT(12),C ON CON 2 OUTPD( 12) C O,"'PCN/ YRCOST/YRCS(5) CON CON COMMON ALI GN, PROF, TFMPL, PAVE,ROUGH, DEMAN, TRAF, NPER, ECCN, MAPOL, CON RBLD,TO POG, GOLGY, CBR, GRDCV, DRA IN, HD)IST, PROD,UXYZ, ECONO, MARK, NUVEH, CON CON VEH, OUTWORK ,OSWTH CON EOUIVA LENCE ( OU,IPRNT ) CON DATA IN SUB/12/ CON DATA TCPO, IOPI / 7,7 / CON K=CCNST CON CON IJ=K CON WRITE(OU,1) K,( -RSTRT(K,J),J=1,4 ) CONSTR(STRT,YR, IJ,CONST,YRlCNT) SUBROUTINE THIS ROUTINE CAUSES THE CCNSTRUCTIGON AND RECONSTRUCTION (WHEN IT THEN COMPUTES THE ACCRUED COSTS DESIRED ) OF A ROAD. PRINTS THESE COSTS AND THEN RETURNS CONTROL TO ROUTINE NFTWRK OR ROUTINE DETER. THE E NTRY POINT SIMCON IS USED FOR 'SIMPLE' CONSTRU CTION. IT IS THIS POINT THAT IS CALLED BY DET ER WHEN RESURFA CING OF AN ASP HALT CP SURFACE TREATED ROAD IS REQUIRED ,TPMF', INTEGFR OU, OYR MOD, OTR ACE,TGROWS ,rNVEH,OSWTH(3),RBLD(11) 1 RECCN( 25), STRT,YR,Y RF,CONST,YR1CNT REAL IN T, MAPOL(20), HDIST(IO), MARK(32) DIMENS ION ALIGN(3),P ROF( 104),TEMPL (15) ,PAVE (12) ,ROUGH(13) 1DEMAN(7 ,3),TRAF(7),EC ON(4),TOPOrG(305),GOLGY(3),GRDCV(4) , 2nRAIN(8 ), PPOD(54), ECO NO(32),VEH(7,12),0UT(150) ,WORK(40), 3UXYZ(25 C H- (O0 16 10 20 30 40 50 60 70 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 320 330 340 350 360 370 380 1 FORMAT ('0 CONSTRUCTION # 1 STRATEGY '/ T20,15,2( 2F10.0-,FIO.0 YEAR TYPE MAINTPOL CON CON CON JO= RSTRT(IJ,2) .CON IOP=O CON IF( JQ.GT.IOPO IOP=1 CON IF( JQ.GT.IOP1 IOP=2 CON CON CHECK IF THIS IS NEW OR PAVEMENT CONSTRUCTION C CON IF((IOP.EQ.O).OR.(IOP.EQ.1)) GO TO 17 CON C CHFCK IF THE ROAD WIDTH IS UNCHANGED. IF IT IS THIS IS A CON CON C TYPE 1 ( PAVEMENT ONLY) RECCNSTRUCTION IF( TEMPL (1). EQ.0ES IGN( 1,JQ)) 1) Or= CON CON C ESTABL ISH DESIGN PARAMETERS CON CON 17 DO 10 I=1,15 10 TEMPL( I)= DESIGN(I,JQ ) CON CON TEMPL ( 12)= TEMPL(1)*2. TE MPL ( 13)= TEMPL(11) CON CON DO 101 1 I=1,12 CON 1011 PAVE( I)= DESIGN(I+15,JQ ) CON C CONVERT LAYER THICKNESSES TO.METERS CON C CON DO 1012 KL=4,12,2 1012 PAVE(KL)= PAVE(KL)/100. CON CON PAVE(11)=PAVE( 1l.)/100. CON C IF( OTRACE.GT.0O) GO TO 939 CON WRITE(OU,78) CON 78 FORMAT(' THE PAVEMFNT DESIGN FOR THIS CONSTRUCTION IS' ) CON CON WRITE(OU ,802) 802 FOPMAT(' WICTH SLOPE SHLD-W D SHLD-SL DTH-WD DTHCON FI LL-SL PAVE-W D DTH-SL CUT-SL 1-SL DTH-WD SIDE-CL') CON WRITE(OU ,830) (TEMPL(I),T=1,10), TEMPIL(12), TEMPL(1 3) CON CON P30 FORMAT(12F10.2) CON WRITE (OU, 803-) )) 390 400 410 420 430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 580 590 600 610 620 630 640 650 660 670 680 690 700 710 720 730 740 THICON LAYERS MAT-TPE THICKNESS MAT-TPE 803 FORMAT(' PAVE-CD SHLD-TPE THICK THICKI ICK MAT-TPE THICK2 CON THICK3') WRITE(OU,830) PAVE CON .CON CONTINUE 939 CON CON CHECK FOR NEW ALIGNMENT C CON IF (( IOP.NE.0). OR. ( YR.EQ.1)) GO TO 19 CON READ NEW TERRAIN AND TOPOGRAPHICAL CATA C CON ISTORE= IN CON WRITE(OU, 192) CON FOPRMAT('0 NEW ALIGNMENT CATA * ) 192 CON CALL PMINI (INSUB) CON CALL PMIN2 .(INSUB) CON IN= ISTORE CON 19 CONTINUE CON IF( YRCS(1).LT.0) GO TO 92 CON 00 9 II=1,5 CON IF (YR.GE.YRCS(II)) GO TO 91 CON 09 CONTINUE CON GO TO 92 CCN 91 JK=II CON 00 11 1=1,20 CON 11 PROD(10+1)= COST(JK,I) CnN 92 CONTINUE CON IF ( OTRACE.GT.0 ) GO TO 931 CON WRITE(OU ,818) (PROD(I), I=11,30) CON PAVEMENT UNIT COSTS AND PRODUCTIVITIES 818 FORMAT('O0 I ' PROD SOURCE TRANSPORT LCOST EQCOST '/ CON CON 2( 5F10.2,30X ) CON 931 CONTINUE CON C CON 74 CONIND=1. CON GO TO 76 CON CON CALL CONSTRUCTION COSTING ROUTINES CON 750 760 770 780 790 800 810 820 830 840 850 860 870 880 890 900 910 1920 930 940 950 960 970 980 990 1000 1010 1020 1030 1040 1050 1060 1070 1080 1090 1100 ENTRY SIMCON(IOP) CONIND=-1. C 76 C C C C CALL HWYCT(IOP) CALL INITL TO INITIALIZE SURFACE PARAMETERS CALL C H H INITL CON CON CON CON CON CON CON CON CON CON CON CON CON CON CON ),I=15,35),0UT(37), CON CON 8CR COST BOR CON SUM COSTS AND PRINT OUTPUT IF DESTRED IF ( OTRACE.GT.2) GO TO 657 IF( OSWTH(1).LT.1 ) GO TO 657 PRINT DETAILED CONSTRUCTICN COST DATA C WRITE(OU,400) ( OUT(I),I=1,14),OUT(36), (OUT(I 1 OUT(59),( OUT(I),I=38,5e),(OUT(I),I=60,72 ) CUT.VOL FILL VOL 400 FORMAT(lHO,T16,'AREA TOTAL'/T14,' LABOR EQUIPMENT TIME lHAUL HOURSHECTARESCON CON 2 CU.M CU. M ,F12.0,T69,4Fl2.0/' CON SITE PRFP.',T9 3 $ $' /' $ CON T21,8FI2.0 / 'OPAVEMENT ' , 4EARTHWORK', MATL.COST HAUL CON T17,'AREA VOLUME A TOTAL'/TCON EQUIP. LAYERCOST LABOR ICOST TIME $CON HOURS $ $ CU.M 216,'SQ.M CON $ $'/ T9,FI2.0,T107,F12.0 / $ 3 1 ' LAYER 1',T21,7Fl2.0/' LAYER 2',T21,7FI2.0/' LAYER 3',T21,CON 17F12.0 /' SHOULDER',F11.0,T107, F2.0/' LAYER 1',T21,7FI2.0/' LAYERCON LFNGTH OCON 2 2',T21,7FI2.0/' LAYER 3',T21,7FI2.0 /' DRAINAGE TOTAL'/ T10,8F12.0 /CON TRANSPORT 3F CULVERT (M)',T74,'SOURCE COST EQUIPMENT ($)'/' OTHER COMPONENTS',2CON 1 1H0,T26,'LABOR ($) 1F14.0/ ' OVERHEAD,SUPERVISICN',FI4.0,F14.0 , T50,t'TOTAL CONSTRUCTICON CON 20N COST FOR THIS PROJECT IS $ ',F12.0) CON CON OUT(42)+ OUT(33)+ OUT(26)+ 657 OUTPT(1)=OUT(3)+OUT(11)+CUT(19)+ CON 1 OUT(49)+ OUT(56)+ OUT(68)+ OUT(70) 1110 1120 1130 1140 1150 1160 1170 1180 1190 1200 1210 1220 1230 1240 1250 1260 1270 1280 1290 1300 1310 1320 1330 1340 1350 1360 1370 1380 1390 .1400 1410 1420 1430 1440 1450 1460 OUTPT(2)= OUT(4)+ OUT(12)+ CUT(20)+ OUT(27)+ OUT(34)+ OUT(43) +OUT(50)+ OUT(57)+ OUT(69)+ OUT(71) OUTPT(3)= OUT(8)+ OUT(16)+ CUT(23)+ CUT(30)+ OUT(39)+OUT(46) +OUT(53)+ OUT(65) 1 OUTPT(4)= OUT (9)+ OUT(17)+ OUT(24)+ OUT(31)+ OUT(40)+ 1 OUT(47)+ OUT(54) + OUT(66) CON CON CON CON CON CON CON C CON 498 DO 133 1=1,4 CON IF ( IODVO.NE.0O) GO TO 134 CON OUTPT(I )=OUTPT( I)/ALIGN( 1) CON 134 OUTPD(I)= OIJTP T( I )*DISC CON SUiM( I )=SUM( I )+ OUTPT( I) CON SUMD(I)=SUMD(I) +OUtTPD( I) 133 CON TOTAL (1)=0UT0T( 1)+OUTPT(2)+OUTPT(3)+ OUTPT(4) TOTAL(2)= OUTPD (1)+ OUTPD(2)+ OUTPD(3)+OUTPD(4) CON CON TOTAL(3)= SIUM(1 )+ SUM(2)+ SUM(3)+ SUM(4) CON TOTAL(4)= SUMD( 1)+ SUMD(2)+ SUMD(3)+ SUMD(4) CON IF(OTRACE,GT.2 ) GO TO 658 CON SUMD I ), I=1,4), WRITF( IPRNT,303 ) ( OUTPT(I), OUTPD(I),SUM(I), CON (TOTAL(I),I=1 ,4 ) 1 (PER KILOMETER )'I/ T30, 'THISCON FORMAT(IHO, T40 ,' CCNSTRUCTION COSTS 303 1 PEPIOD ',T65,' SUM TO DATE'/ T25,' ACTUAL 0 ISCOUNTED' ,T55CON DISCOUNTED '/' LABOR',T20,2(2Fl5.0 ,5X)/ ' EQUIPMCON 2, 'ACTUAL ' MATERIAL ' ,T20,2(2Fl5.0,5X )/ ' TRANSPORTCON 3ENT',T20, 2(2F15 .0,5X)/ T20,2(2FI 5.0,5X ) ) CON ',T20, 2(2F15.0,5X)/ ' TOTAL', 4ATION CON 658 CONTINUE CON C CON CON COMPUTE FOREIGN CAPITAL UTILIZED IN CONSTRUCTION C CON CON FOREIGN COSTS ARE BROKEN INTO LABOR, SOURCE AND EQUIPMENT CON COMPUTE ACTUAL COST FOR PERIOD CON 0.) GO TO 331 IF ( ECCN (2) .GT. CON DO 311 I=1,3 CON II =(I -1)X*4 + 1 CON 311 OUTFR(I I)=FOREX( I+3)*OUTPT(I) 1 1470 1480 1490 1500 1510 1520 1530 1540 1550 1560 1570 1580 1500 1600 1610 1620 1630 1640 1650 1660 1670 1680 1690 1700 1710 1720 1730 1740 1750 1760 1770 1780 1790 1800 1810 1820 COMPUTE DISCOUNTED COST FOR THIS PERIOD 00 315 I=1,3 II= (I- 1)*4 +2 315 OUTFR(I I) = FORFX(I+3)*OUTPD( I C ACCUMUL ATED COST TO DATE 00 320 1=1,3 ll=(I-1 )*4+3 320 OUTFR(I I) =FOREX(I+3)*SUM(I) C COMPUTF ACCUMULATED COSTS DISCOUNTED TO DATE DO 325 I=1,3 II= 1*4 325 OUTFR(II)= FOREX(T+3)*SUM 0(I) C TOTAL FORPEIGN COSTS FOR CCNSTRUCT ION OUTFR(13) =0. OUTFR(14) =0. OUTFR(15) =0. OUTFR(16) =0. J=U DO 327 I=13,16 J=J+1 DO 327 JJ=J,12,4 327 OUTFR(1) =OUTFR(I) +OUTFR (J J) C COMPUTE FOREIGN COSTS IN DCLLARS DO 330 I=1,16 330 OUTFRS(I)= OUTFR(I)-XRATE 332 331 CON CON CON 4 CON CON CON CON CON CON CON CON CON CON CON CON CON 1830 1840 1850 1860 1870 1980 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 CON 1900 CON CON CON CON 2000 2010 2020 2030 CON 2040 CON CON CON CON IF ( OTRACE.GT.0) GO TO 331 CON WRITE(OU,332) CON 1 FMONY, (CUTFR(),IOUTFR(I+1),CUTFR(I+2),OUTFR(I÷+3),O IUTFRS( I )CON I ,OUTFRS(I+1),OUTFRS(I+2),OUTFRS(I+3), CON I=1,13,4 ) FORMAT(1H0,T50,'OFFSHORE COSTS FOR CONSTRUCTION'/ T30,'IN ',3A4, CON ) /CON 2 T80,'IN DOLLARS'/ T14,2(7X,'THIS PERIOD',15X,'SUM TO DATE ',7X CON 2 T14, 4( 6X,'ACTUAL DISCOUNTED' ) / 2 ' LABOR',T13,8F13.0/' FQUJIPMENT',T13,8Fl3.0/ ' MATERIAL' ,T13 9 CON ) CON 3 8F13.0 /'TOTAL',T13,8F13.0 RETURN CON 2050 2060 2070 2080 2090 2100 2110 2120 2130 2140 2150 2170 2180 2190 194