See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/273177732 Risk Management for Asphalt Road Construction and Maintenance under Performance-Based Contracts Article in International Journal of Construction Education and Research · January 2015 DOI: 10.1080/15578771.2014.990121 CITATIONS READS 10 13,178 2 authors: Mohammed S. Hashem M. Mehany Angela Acree Guggemos Colorado State University Colorado State University 41 PUBLICATIONS 126 CITATIONS 27 PUBLICATIONS 946 CITATIONS SEE PROFILE SEE PROFILE All content following this page was uploaded by Mohammed S. Hashem M. Mehany on 12 January 2016. The user has requested enhancement of the downloaded file. This article was downloaded by: [Missouri State University] On: 09 February 2015, At: 07:08 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK International Journal of Construction Education and Research Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/uice20 Risk Management for Asphalt Road Construction and Maintenance under Performance-Based Contracts a b Mohammed S. Hashem M. Mehany Ph.D. & Angela Guggemos Ph.D. a Missouri State University, Springfield, Missouri, USA b Colorado State University, Fort Collins, Colorado, USA Published online: 06 Jan 2015. Click for updates To cite this article: Mohammed S. Hashem M. Mehany Ph.D. & Angela Guggemos Ph.D. (2015): Risk Management for Asphalt Road Construction and Maintenance under Performance-Based Contracts, International Journal of Construction Education and Research, DOI: 10.1080/15578771.2014.990121 To link to this article: http://dx.doi.org/10.1080/15578771.2014.990121 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. 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Terms & Downloaded by [Missouri State University] at 07:08 09 February 2015 Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions International Journal of Construction Education and Research, 00:1–24, 2015 Copyright © Associated Schools of Construction ISSN: 1557-8771 print/1550-3984 online DOI: 10.1080/15578771.2014.990121 Risk Management for Asphalt Road Construction and Maintenance under Performance-Based Contracts MOHAMMED S. HASHEM M. MEHANY, PH .D. Downloaded by [Missouri State University] at 07:08 09 February 2015 Missouri State University, Springfield, Missouri, USA ANGELA GUGGEMOS, PH .D. Colorado State University, Fort Collins, Colorado, USA Contractors have been the main risk bearers in most road construction and maintenance projects, especially when they are working under higher-risk delivery systems such as Performance Based Contracts (PBC), where the contractors are more likely to be responsible for both the construction and maintenance of the road for a certain warranty period. This research identified and analyzed the risks that the contractor is subject to under PBCs for hot mix asphalt (HMA) road construction and maintenance projects. The study used a mixed methods research design and was divided into three phases. In the first phase, employing a detailed literature review along with industry interviews, twenty-nine risks were identified in the construction and maintenance phases. In the second phase, risk severity rankings were calculated using probability and impact data that was collected from several contractors and a state agency. In the final phase, a correlation analysis was conducted. The results of this analysis will enable contractors to make adjustments and modifications to address the highest and most severe risks. Keywords asphalt contractors, asphalt road construction, asphalt road maintenance, performance based contracts, risk management Introduction Government agencies and the Federal Highway Administration (FHWA) are starting to see the benefits of using contracts in which a contractor is responsible for both the construction and maintenance of roadways. This work is often performed under a Performance-Based Contract (PBC) where payments for the construction and maintenance of roads are explicitly linked to the contractor successfully meeting or exceeding certain clearly defined minimum performance indicators and measurements stated in the contract specifications (Stankevich, Qureshi & Queiroz, 2005). To be successful under a PBC, contractors should take into account most of the risks associated with construction and maintenance throughout the contractual period. Risk in the construction and maintenance industry has increased with project size and cost. One might even say that today construction is mainly risk management. Risks are found throughout all phases of a project and vary greatly according Address correspondence to Mohammed S. Hashem M. Mehany, Missouri State University, Glass Hall 207, 901 South National Avenue, Springfield, MO 65806, USA. E-mail: mohammedmehany@missouristate.edu 1 Downloaded by [Missouri State University] at 07:08 09 February 2015 2 M. S. Hashem M. Mehany and A. Guggemos to the type of construction, the contracts involved, and the type of delivery system. This article focuses on a very specific subset of the overall industry where the contractors are contracted to build and maintain hot mix asphalt (HMA) roadways under PBC. For these conditions, managing risk during the maintenance phase may be even more important than during construction since risk management for maintenance can be more complex. Also, the duration of maintenance is much longer than construction; and estimating costs and risks is more difficult and must take into consideration the time value of money, the fluctuation of markets, as well as inflation. Moreover, road projects have always been among the riskiest construction projects due to their long duration of construction phase, quality concerns, and likely cost overruns. Like any construction project, road construction and maintenance projects have three main components that can be subjected to risks. These main components are cost, time and quality. But in road construction, problems and risks in any of these three areas can be amplified because of project size and duration and a lot more unforeseen conditions. Material and energy price increases combined with economic problems that raise inflation worldwide have an impact on all industries. Road construction and maintenance projects are particularly affected since rising energy costs drive up material costs and when energy and material prices increase, construction projects decline or slow down. As a result, road construction and maintenance contractors are facing substantial economic and technical risks. Specifically, under contracts where they build and maintain HMA roadways such as PBCs which are fixed price contracts that cover a long span of time with a warranty period included in the contract. Warranties can be used as part of a PBC to ensure that performance goals are met for the required maintenance period. One example of a PBC with a warranty period is the M115 project completed by Michigan DOT (MDOT) where a warranty period of 5 years was used to ensure the ride quality after construction. As part of the bidding process, MDOT allowed the bidders to offer a warranty period longer than 5 years, giving them additional points towards the best value award (Rao, Mallela, & Hoffman, 2009). This is very different from the more commonly used unit price contracts where the specifications for the construction or maintenance are literally prescribed rather than performance-based. The purpose of this research is to develop a better understanding of the risks associated with the construction and maintenance phases under contracts where the contractors both build and maintain HMA roadways. The first objective is to identify the most severe risks and their impact for road construction and maintenance contractors who build and maintain HMA roadways. The second objective is to quantify the severity/magnitude of those risks. The scope and application of this study is limited to contractors for HMA road projects under PBCs for construction and maintenance. Literature Review Risk Management Risk management is the process concerned with planning, identification, assessment, analysis, responses, monitoring, and controlling project risk (PMBOK, 2004). This definition is fairly comprehensive as it includes the three main steps of any risk management process which are risk identification, assessment/analysis, and response. Much research focuses on risk management tools and their use through the risk management process to enable the creation of project-specific risk response plans (Hall, 2000; PMBOK, 2004). The output of these tools falls under two categories: (1) risk mitigation and/or (2) preventive actions. Mitigating actions allow the contractor to reduce the probability and impact of the adverse risks to acceptable limits (e.g., acquiring more expertise on the management team Downloaded by [Missouri State University] at 07:08 09 February 2015 Risk Management for Asphalt Road Construction and Maintenance 3 to eliminate some risk from the start of the project procurement process). Contractors use preventive actions to eliminate threats to safeguard the project’s objectives (e.g., choosing more stable suppliers). One of the noted deficiencies in the construction industry is unbalanced risk allocation in which most of the risk is allocated to the contractor instead of allocating the risk to those in the best position to carry it because they have the best resources, the best information, or the best expertise (Diepenbrock, Davison, Lichtig, & Rudolph, 2002). According to various studies (Bing, Akintoye, Edwards, & Hardcastle, 2005; Gruneberg, Hughes, & Ancell, 2007; Hartman & Snelgrove, 1996; Kartam & Kartam, 2001), it is apparent that the contractor is affected by risks of all types including economic and environmental. Consequently, risk accountability can be higher under PBCs that extend and magnify the contractor’s risk accountability towards the project. For this reason, this research is focused on quantifying the risks for contractors involved in both road construction and maintenance. Contractor Risk Accountability In general, the construction industry is highly risky for all participants. The level of risk, however, varies throughout the life cycle phases of a project and is influenced not only by the type of contract and its particular specifications, but also by the political and economic environment. Risk allocation was created to help distribute these risks. Risk allocation can be defined simply as the “allocation of proportional risk to all parties of a contract” and that the risk should be borne by those in the best position to carry it because they have the best resources, the best information, or the best expertise (Diepenbrock et al., 2002). In reality, most participants try to transfer the risk to others, resulting in disputes, especially between the project owner and the contractor. Many researchers have shown that the contractor typically bears most of the risk, especially during the construction phase. Kartam and Kartam (2001) examined risk allocation and significance in the Kuwaiti construction industry and the study results indicated that the contractor has some allocation of every risk except the force majeure. Contractors also had the highest percentage of the most significant risks (e.g., labor, material and equipment availability), including those that are least controllable (e.g., differing site conditions and inflation). This accountability will be more significant under PBCs where the risks are allocated for an even longer period of time. The delivery system of the contract is the vehicle for risk allocation and risk management in the contract (Molenaar, Ashley, & Diekmann, 2006). Generally, road projects delivery systems falls under the normal Design-Bid-Build (DBB), Design Build (DB), Construction Manager at Risk (CM At-Risk) (AGC, 2014). Other delivery systems coming into the recent decades are the Integrated Project Delivery (IPD), Private Public Partnership (PPP), Build Operate Transfer (BOT) and Performance Based Contracts delivery (PBC) along with others. Much Literature discussed the DBB, DB and CM At-risk risk management allocation in road projects. Much of this literature has been devoted to comparing the DBB and DB risk management. They mostly pointed that owner bears a lot more risk in the case of DBB projects such as design and specification changes, Errors and Omissions (E&O), integration of multiple prime’s contractors risk and exposure to multi-party disputes. In contrast, most of these risk are transferred to the contractor (Design-Builder) in the case of DB delivery system (Prieto, 2012). Others have compared the three delivery systems together and the risk allocation ratios among the major three delivery systems such as the Utah Department of Transportation (UDOT) (McMinimee et al., 2009) as in Figure 1. Downloaded by [Missouri State University] at 07:08 09 February 2015 4 M. S. Hashem M. Mehany and A. Guggemos Figure 1. UDOT risk ratios. Source: McMinimee et al. (2009). The review of the published literature of similar studies suggests that most of the past efforts were focused either on general risks for different parties or independent phases of construction or on conventional delivery systems (Ashley et al., 2006; Berdica, 2002; Perera, Dhanasinghe & Rameezdeen, 2009). No study adopted a holistic approach to examine the construction and maintenance risks under the performance-based delivery system. The presented research study fills this gap by thoroughly examining the critical risks during the construction and maintenance phases of HMA roadways under the PBC delivery system that should be considered by contractors. Methodology and Data Sources After examining the research methodologies adopted in similar studies, it was decided that a mixed-methods research methodology would be adopted using both quantitative and qualitative data to accomplish the research objectives. Mixed-methods research design is a procedure for collecting, analyzing, and mixing both quantitative and qualitative research and methods in a single study to understand a research problem (Creswell, 2008). The qualitative research includes expert interviews to validate risk identification and assist with the selection of the most significant risks. Quantitative research includes risk probability and risk impact scores to assess the ranking, frequency, and magnitude of risks as well as correlation analysis of the most significant risks. The research design is shown in the methodology framework as illustrated in Figure 2. The framework is divided into three main phases representing the risk management framework: risk identification, risk assessment, and risk analysis. Phase 1 – Risk Identification Risk identification is the first phase in any risk management process where risks are identified, shortlisted and documented. It develops the foundation for the next phases of assessment and analysis and ensures the risk management effectiveness (Tchankova, 2002). This phase is very important for the success of the risk management process since failure to identify the significant risks will result in ineffective risk management considering the fact that those non-identified risks will become non-manageable (Greene, Trieschmann, & Gustavson, 1991). Elements of this phase include: extensive literature review, creation of a risk breakdown structure (RBS) tool, and expert interviews to identify the most significant risks for the HMA construction and maintenance phases. Risk Management for Asphalt Road Construction and Maintenance Risk Identification using RBS Shortlisting the most significant Risks Risk Probability (P) & Impact (I) Data Collection Risk Severity scores Identification of the most severe risks for HMA Construction & maintenance phases Phase 1 – Risk Identification 5 Correlation Analysis Phase 3 – Risk Analysis Downloaded by [Missouri State University] at 07:08 09 February 2015 Phase 2–Risk Assessment Figure 2. Research design and methodology framework. Risks Identification using Risk Breakdown Structure (RBS) An in-depth literature review in conjunction with the author’s 10 years of road construction experience were used to identify the risks associated with HMA construction and maintenance. A risk breakdown structure was utilized to identify the risks at different stages of the construction and maintenance phases. A RBS is a source oriented grouping of risks to organize and define the total project risk exposure through the different levels that represent the overall project sources of risk (Hillson, 2002). It is considered a good fit for this research since it is the best way to deal with a large amount of data through different processes in the HMA construction and maintenance phases by providing a hierarchical structuring of risks for different processes instead of just listing the risks (Hillson, 2003). This is because a simple list of risks cannot represent the different areas and processes of HMA construction and maintenance project phases in a comprehensive manner as can be done with a RBS. Shortlisting the Most Significant Risks To shortlist the RBS identified risks into the most significant risks for the construction and maintenance phases, open-ended expert interviews were conducted each of which lasted for several hours. All of the expert professionals were identified through academic and industry referrals with the qualifications of having at least 10 years of HMA road construction and/or maintenance project experience and have worked with PBC delivery systems. The expert interviews were conducted with 3 industry professionals (1 county road and bridge director, 1 consultant and 1 HMA contractor) who combined have about 60 years of experience in the road projects industry. They were asked to add, delete, combine or modify the list of risks for both the construction and maintenance phases that resulted from the RBS process to identify the most significant risks. Phase 2 – Risk Assessment Risk assessment is the next phase of the risk management process where the risks are objectively evaluated and their nature, types, and effects are explored. The risk assessment can be a determination of quantitative or qualitative values of the risk and in this research, a quantitative approach was taken to measure the risks’ values. 6 M. S. Hashem M. Mehany and A. Guggemos Quantitative risk assessment has two main components for the evaluation. The first component, risk impact (I), measures the magnitude of the risk if it happens while the second component, risk probability (P), measures the likelihood or frequency that the risk can occur. All values are measured in percentages. Downloaded by [Missouri State University] at 07:08 09 February 2015 Risk Probability and Impact Data Collection The risk probability and impact data were collected from 5 different HMA contractors and the Larimer county roads department through different expert interviews where they were asked to provide P and I scores for every shortlisted risk in the HMA construction and maintenance phases. This sample size of 6 represents about 60% of the volume ($) of the road construction and maintenance industry in the state of Colorado which is thought to be an appropriate sample size to represent the road industry in Colorado. Risk Severity Scores After receiving the P and I scores for every risk on the shortlist, the risk severity scores on which a risk can be assessed were calculated. Severity (S) is calculated as a product of both probability and impact as in the following equation: S=P × I (1) Identification of the Most Severe Risks for HMA Construction and Maintenance Phases After the risk severity scores have been calculated in the previous step, the risks were categorized according to their severity scores where the most severe risks were identified so as to be further analyzed in the next phase. Phase 3- Risk Analysis Risk analysis is usually referred to as quantitative risk analysis. The key purpose of this phase is to combine the effects of the various identified and assessed risks into an overall holistic approach to provide the basis for evaluating the effectiveness of the risk management framework and lay the foundation for any future risk allocation strategies and risk response plans (Ashley et al., 2006). Risk analysis can be achieved using different tools and methods which are selected according to the nature of the study and the risks measurement capabilities. This research will use one of the most common risk analysis tools, correlation statistical analysis. Correlation Statistical Analysis Correlation analysis is generally defined as a statistical analysis that is used to test, describe and measure the degree of association between two or more variables and in this research case, it is the association between the different risks (Creswell, 2008). Correlation analysis is performed in this research to determine the tendency and the patterns for the occurrence of different risks in the different processes and express the degree of association between the risks. Different types of correlation can be applied. However, a Pearson correlation statistical analysis was selected rather than a Spearman correlation type since most of the correlations Risk Management for Asphalt Road Construction and Maintenance 7 of the variables tend to have a linear relationship which was checked and proofed through several scatter plots drawn between those variables. The end results were represented in the form of a correlation matrix using Statistical Package for Social Science (SPSS) software indicating the different risk correlation scores and their association factors. Data Collection and Analysis Downloaded by [Missouri State University] at 07:08 09 February 2015 Phase 1 - Risk Identification using Risk Breakdown Structure (RBS) The RBS was used to identify the risks for each activity within both the construction and maintenance phases. As a result of the extensive literature review as mentioned in the methodology section, the RBS was created to represent the different risks during each process within the construction and maintenance phases. Figure 3 shows the different processes during the construction phase from the site investigation until the project handover process. The bold boxes represent the major construction processes; sub-processes are unboxed, and risks are shown in italics. At the top, risks that occur throughout the construction phase are noted. Using this RBS, the risks associated with the different processes in the construction phase can be easily identified. For example, during paving, the paving speed is a risk associated with the sub-process of the laydown operation. It is worthy to note that at the HMA mixing facility, there are two categories: (1) risks that can occur within the mixer itself such as the mixing temperature, and (2) risks that can occur for the supplemental components for the mixing facility such as the operator and the feeding equipment. Another RBS was created to identify the maintenance phase risks as shown in Figure 4. However, the maintenance was organized in a slightly different manner to address different types of maintenance. The maintenance phase was divided into two main types of maintenance, preventive and corrective. Within each maintenance type, there are different maintenance applications and techniques and the risks associated with each. Finally, some of the risks identified are associated directly with the equipment crew’s knowledge and experience during the maintenance project. After using the RBS to identify the risks for both the construction and maintenance phases, the risks were listed in Table 1 (construction risks)and Table 2 (maintenance risks). The risk types, nature, and effects are based on the following definitions and categorization: Risk Type. The risk type refers to the risk categorization when it happened and materialized in the construction or maintenance process. In other words, it is how the risk is considered when it happened. The types of risks can be categorized as economic, technical, time, safety, and force majeure. Risk Nature. The risk nature refers to the reason or phenomenon for the origin of the risk. The nature of risks can be categorized as contractual, technical, timing, hazard, and act of God. Risk Effects. The risks in the construction and maintenance phases can affect several aspects of a HMA road project. Mainly the risks can have an effect as additional cost, additional time, added extensive maintenance, negative environmental effects and, in some cases, it can affect the contractor’s portfolio. The categories of the risk effects that were addressed in Tables 1 and 2 are the following: 1. Cost effect—additional cost to the project and in some cases, a cost to the public 2. Schedule effect—additional time required to complete the project 8 M. S. Hashem M. Mehany and A. Guggemos Throughout the Construction phase Risk of innovation investment Force Majeure Bonding Capacity Price Fluctuations Site investigation Hauling Road conditions Traffic Adjustments Available spaces for Equipment HMA Mixing (Facility) Mix Temp. Changing Mixes Emergency repairs Downloaded by [Missouri State University] at 07:08 09 February 2015 Feeding Equipment Long term storage Voids control Operator Break Down Absenteeism Transportation Plant Positioning Truck Loading Lubrication Dumping segregation Truck Hauling inefficient use Weather Covering Distance Bad covering procedures Paving MTV Waiting time for grading contractor Feeding pavers Availability Soft Sub base Stoppage time Laydown paving speed screed adjustments Compaction % of crushed Aggreg. Mass Non- Driven drums & PTR use Modification of mix design Parking HMA cooling rate Speed Traffic vibratory rolls Distance to paver Handing over PBC end results Test variability Go - no go approach Q.C & Q.A. Testing Frequency Extraction Test Solvent Core & nuclear gage Figure 3. RBS for the risks associated with the HMA construction phase. 3. Maintenance effec—additional maintenance with associated maintenance costs 4. Negative environmental effect—in terms of non-environmentally friendly substances used in testing and inspection processes 5. Portfolio effect—limits the contractor’s financial ability to take on more projects. Phase 1 – Shortlisting the Most Significant Risks Through the expert interviews mentioned in the methodology section and with feedback and suggestions from the interviewees, a shortlist of the most significant risks was created and approved by them. As a result, the risks listed in Table 1 and Table 2 were reduced from 42 to 18 different risks for the construction phase and from 18 to 11 risks in the maintenance phase as shown in Table 3. Risk Management for Asphalt Road Construction and Maintenance 9 Table 1. Risks associated with HMA construction Downloaded by [Missouri State University] at 07:08 09 February 2015 Risk name Throughout the project Risk of investment in innovation Prices fluctuation Bonding capacity Delayed owner payments Weather changes Site investigation Traffic adjustments Hauling road condition Available equipment spaces HMA facility Emergency repairs Mix temperature Changing mixes Voids control Long term storage Feeding equipment breakdown Operator absenteeism Transportation Plant positioning Segregation at dumping Distance to site Inefficient use Bad covering procedures Paving Waiting time for contractor Soft sub base MTV-availability Stoppage time Paving speed Screed adjustments Compaction Percent crushed aggregates mass Usage of non-driven drums/PTR Modification of mix design mistakes Parking HMA cooling rate Compaction speed Risk type Risk nature Risk effect Economic Contractual Cost Economic Economic Economic Force majeure Contractual Contractual Contractual Act of God Cost-Schd. Portfolio Cost-Schd. Cost-Schd. Technical Technical Technical Location Location Location Cost-Schd. Cost-Schd. Cost-Schd. Technical Technical Technical Technical Technical Technical Technical Technical Technical Technical Technical Technical Cost-Schd. Cost-Schd. Cost-Schd. Cost-Schd.-Maint. Cost-Schd.-Maint. Cost-Schd. Technical Technical Cost-Schd. Technical Technical Technical Technical Technical Location Technical Location Technical Technical Cost-Schd. Cost-Schd.-Maint. Cost-Schd. Cost-Schd. Cost-Schd.-Maint. Time Technical Economic Technical Technical Technical Contractual Contractual Technical Technical Technical Technical Cost-Schd. Cost-Schd. Schd.-Maint. Cost-Schd.-Maint. Cost-Schd.-Maint. Cost-Schd.-Maint. Technical Technical Cost-Schd.-Maint. Technical Technical Cost-Schd.-Maint. Technical Technical Cost Technical Technical Technical Location Time Technical Cost-Schd.-Maint. Schd Cost-Schd.-Maint. (Continued) 10 M. S. Hashem M. Mehany and A. Guggemos Table 1. (Continued) Downloaded by [Missouri State University] at 07:08 09 February 2015 Risk name Risk type Risk nature Risk effect Traffic effect on joints Vibratory rolls on long. joints Distance to paver Handing over Test variability “Go No-Go” approach Testing frequency Extraction test solvent Technical Technical Technical Technical Maintenance Cost-Schd.-Maint. Technical Technical Maintenance Technical Technical Technical Technical Contractual Contractual Technical Contractual Core & nuclear Technical Contractual Cost-Schd. Schd. Cost-Maint. Negative environmental Cost-Maint. Schd. = Schedule, Maint. = Maintenance. Although most of the risks are clear as listed, some require explanation. For the construction phase, • Long-term storage: Problems due to long term storage causing drainage and oxidation of the asphalt cement. • Distance to paver: Distance of the compactor to paver affecting the cooling rate of HMA and length of time the material is hot enough to be compacted. • Go, No-Go approach: Stopping during the paving process due to rejection by inspection for not meeting the required performance specifications for the project, causing delay of the whole construction phase due to a controllable section of the road being rejected. For the maintenance phase: • Cleaning procedure as well as the cleanness of cover aggregate should be done at its best practices; otherwise the asphalt will form a strong bond with the debris on the surface instead of the road surface. • Roughness components consideration: If not taken into consideration, the thin overlay will not remove that roughness (doesn’t achieve its goal). The total overlay thickness should vary depending on the type of roughness components present in the road profile in order to allow greater overlay depths when warranted by a roughness survey. • Use of 1 size cover aggregate for a chip seal is more expensive but can reduce the amount of future maintenance required in the performance period. Phase 2 - Risk Probabilities and Impacts Data Collection After the risks were identified and categorized (Tables 1 through 3), the probability (P) and impact (I) scores of the most significant risks were collected through interviews. For each risk, all the respondents provided both the P and I scores. The respondents were represented by five HMA contractors and a public works (Larimer County) director. The responses are shown in Table 4 for construction risks and Table 5 for maintenance risks. Risk Management for Asphalt Road Construction and Maintenance 11 Table 2. Risks associated with HMA maintenance Downloaded by [Missouri State University] at 07:08 09 February 2015 Risk name Throughout the performance period Weather changes Infrastructure deterioration Preventive maintenance Excess asphalt application Non-porous HMA surface Excess/High viscosity rejuvenators Loose aggregate on high speed/vol. roads Cleanness of cover aggregate Use of 1 size aggregate Binder & cover aggregate quant. calibration Cleaning procedure Excessive aggregate application Compaction by steel-wheeled roller Uniform asphalt binder spray Adjustment of asphalt binder to aggregate absorption Early traffic opening Use of natural sands when skid resistance required Safety issues associated Corrective maintenance Insufficient compaction Edges leveling Temporary (cold) repair costs Roughness components consideration Levelling courses overruns Performance LCC Risk type Risk nature Risk effect Force majeure Technical Act of God Technical Cost Cost Technical Technical Technical Technical Technical Technical Cost Cost Cost Technical Location Public cost Technical Technical Technical Time Technical Technical Cost Cost Cost Technical Technical Technical Technical Technical Technical Cost Cost Cost Technical Technical Technical Technical Cost Cost Technical Technical Location Technical Cost Cost Safety Hazard Cost Technical Technical Technical Technical Technical Technical Technical Technical Cost Cost Cost Cost Technical Economic Technical Contractual Cost Cost One should note the major discrepancies between the different ratings for the P and I scores not only between the governmental agency and the contractors but also between the contractors themselves. The weather probability score was high (60% to 100%) from all the parties surveyed with only one contractor giving it 30%. However, the weather impact had a very high range from almost nothing to a score of 65% with the majority scoring the weather fairly low. This can be attributed to the fact that weather is one of those risks that is almost impossible to account for or to make a contingency account in your bid as a contractor. The “segregation at dumping” risk had consistent P and I scores (50% to 60% for both) from all respondents. However, those scores are not as accurate as they seem since they measure impact or probability on their own. For that reason, a severity score can make a better assessment for those risks as is discussed in the following section. 12 M. S. Hashem M. Mehany and A. Guggemos Table 3. Most significant construction and maintenance risks Level/Process Downloaded by [Missouri State University] at 07:08 09 February 2015 Throughout the construction phase Construction risks Level/Process Maintenance risks Risk of investment in innovations Price Fluctuation Bonding capacity Delayed owner payments Weather changes Throughout the maintenance phase HMA mixing facility Emergency repairs Changing mixes Voids control Long term storage Preventive maintenance Cleanness of cover aggregate Binder & cover aggregate quant. calibration Cleaning procedure Excessive aggregate application Transportation paving Segregation at dumping MTV-availability Stoppage time Paving speed Screed Corrective maintenance Insufficient compaction Roughness components consideration Leveling courses overruns Compaction % of crushed aggregate mass Compaction speed Distance to paver “Go No-Go” Approach Handing over Weather changes Infrastructure deterioration Non-porous HMA surface Excess/high viscosity rejuvenators Phase 2 – Risk Severity Scores The risk severity scores were used as a bridge between the risk identification and the risk analysis where each table has the severity scores resulting from the product of probability and impacts associated with each risk that were provided in Tables 4 and 5. The severity of each risk was calculated as an average of the different scores of the collected data as shown 13 Risk of investment in innovations Price fluctuations Bonding capacity Delayed owner payments Weather changes Emergency repairs Changing mixes Voids control Long-term storage Segregation at dumping MTV-availability Stoppage time Paving speed Screed adjustments % of crushed aggregate mass Compaction speed Distance to paver “Go No-Go” approach Risk P% 50 80 80 20 60 4 5 50 5 65 5 60 60 60 50 60 60 5 I% 1 50 4 5 0 10 10 25 50 20 10 20 20 20 20 20 20 10 Larimer County P% 50 40 80 1 60 4 50 5 1 65 5 80 80 80 5 10 10 5 I% 1 40 4 15 5 10 5 60 5 60 0 5 5 5 60 10 10 55 Contr.1 Table 4. Construction risk probability (P) and impact (I) raw data P% 85 90 80 65 30 4 0 50 0 65 5 90 90 90 50 85 85 1 I% 0.5 50 4 4 65 10 5 30 5 50 10 10 10 10 30 5 5 0 Contr.2 P% 10 70 10 5 100 5 10 15 5 70 0 60 60 60 20 50 50 5 I% 5 30 30 15 8 10 10 50 20 35 0 10 10 10 25 20 20 20 Contr.3 Downloaded by [Missouri State University] at 07:08 09 February 2015 P% 10 65 11 10 100 3 5 20 3 60 10 50 50 50 35 50 50 10 I% 5 40 28 15 5 10 8 50 50 50 10 20 20 20 20 30 30 50 Contr.4 P% 57 80 30 12 100 5 15 20 10 60 10 40 40 40 10 35 35 5 I% 1 43 11 17 10 8 10 25 7 58 2 20 20 20 20 20 20 40 Contr.5 14 Weather changes Infrastructure deterioration Non-porous HMA surface Excess/high viscosity rejuvenators Cleanness of cover aggregate Binder & cover aggregate quant. calibration Cleaning procedure Excessive aggregate application Insufficient compaction Roughness components consideration Leveling courses overruns Risk P% 60 5 4 4 50 10 5 30 10 50 5 I% 0 10 10 11 5 5 10 10 10 60 40 Larimer County I% 5 1 15 25 4 4 10 4 25 60 40 Contr.1 P% 5 5 5 8 7 5 25 5 10 50 5 Table 5. Maintenance risk probability (P) and impact (I) raw data P% 7 5 10 10 3 5 10 5 20 10 85 I% 4 10 9 30 10 8 20 10 27 18 10 Contr.2 P% 40 10 5 10 4 5 20 10 8 50 50 I% 10 8 10 40 20 16 20 8 50 60 40 Contr.3 Downloaded by [Missouri State University] at 07:08 09 February 2015 P% 30 5 10 10 10 5 20 20 15 20 50 I% 10 20 10 38 15 8 15 5 23 70 30 Contr.4 P% 50 10 5 13 5 5 20 12 10 25 57 I% 4 20 20 20 20 10 18 10 20 80 30 Contr.5 Risk Management for Asphalt Road Construction and Maintenance 15 Downloaded by [Missouri State University] at 07:08 09 February 2015 in Table 6 for the construction risks and Table 7 for the maintenance risks. The risks were listed in order of decreasing severity. Based on these severity scores, the two most severe risks during the construction phase are price fluctuation (30%) and segregation at dumping (29%). A second group of risks have severity scores in the range of 7% to 9%: voids control, compaction speed, distance to paver, stoppage time, paving speed, screed adjustments, weather changes and percentage of crushed aggregates. The remaining risks have severity factors of approximately 3% or less. For the maintenance risks, based on the severity scores, the most severe risks are the roughness components consideration (21%) and the leveling course overruns (11%). The remaining risks have very low scores (< 3%) compared to the top two risks. Phase 3 – Correlation Analysis for Construction Phase The Correlation analysis was performed using SPSS statistical software. The variables in this research are the shortlisted construction risks listed in Table 3. Those variables were measured in an ordinal and scale measures since they are not dichotomous variables to be measured in nominal measurement nor are they intervals to be measured in ratio measurement. A Pearson correlation statistical analysis was performed after descriptive statistics were determined for each variable (risk). A sample of the correlation statistical analysis results is included in the Appendix. The first table in the appendix provides descriptive statistics (mean, standard deviation, and N) for the variables to be correlated. The correlation table shows the Pearson correlation coefficients, and two tailed significance (Sig.) levels. As an example, the Pearson correlation coefficient between “voids control” and “insufficient compaction” is .84; the significance value is .036. So the correlation between the two risks is statistically significant because the sig. value (.036) < .05 so we can state that there is an association between “voids control” and “insufficient compaction”. Since the correlation is positive, the more insufficient compaction happens onsite, the more undesired voids ratios will be encountered in the project. The same interpretation can be applied to the rest of the variables in the table. Table 8 demonstrates the relationship between the different construction phase variables (risks), where the first two columns describe the correlated variables, the third column is the significance value which represents the significance of the relationships (X < .05), and the last column is the Pearson correlation coefficient which indicates the degree of the association (correlation) between the variables in the table. It is worthy to note that those are not only the significant relationships but also they are the most logical correlations meaning that those relationships are practical to the onsite construction environment. Phase 3 – Correlation Analysis for Maintenance Phase In the maintenance phase, however, the research has accounted for only two of the risks (not included in the correlation analysis) encountered during the maintenance phase since they are the most common and most severe risks. The first was the roughness component consideration, where the HMA overlay’s main purpose is to reduce roughness, restoring the skid resistance and protecting pavement deterioration in parallel. If not taken into account during the determination of the overlay thickness, a thin insufficient HMA overlay will be just another inefficient structural layer that will not help in the road improvement process the way it was intended. The other risk in the HMA overlay is the leveling course application, since it can cause a cost overrun for the contractor due to excess thickness in some 16 Larimer .50 40.00 3.20 1.00 0 .40 .50 12.50 2.50 13.00 0.50 12.00 12.00 12.00 10.00 12.00 12.00 .50 Construction risks Risk of investment in innovations Price fluctuation Bonding capacity Delayed owner payments Weather changes Emergency repairs Changing mixes Voids control Long-term storage Segregation at dumping MTV-availability Stoppage time Paving speed Screed adjustments % of crushed aggregate mass Compaction speed Distance to paver “Go No-Go” approach Table 6. Construction risks severity analysis .50 16.00 3.20 0.15 3.00 .40 2.50 3.00 .05 39.00 0 4.00 4.00 4.00 3.00 1.00 1.00 2.75 Contr. 1 .43 45.00 3.20 2.60 19.50 .40 0 15.00 0 32.50 .50 9.00 9.00 9.00 15.00 4.25 4.25 0 Contr. 2 .50 21.00 3.00 0.75 8.00 .50 1.00 7.50 1.00 25.00 0 6.00 6.00 6.00 5.00 10.00 10.00 1.00 Contr. 3 Individual Severity Scores % .5 26.00 3.10 1.50 5.00 .30 .40 10.00 1.50 30.00 1.00 10.00 10.00 10.00 7.00 15.00 15.00 5.00 Contr. 4 Downloaded by [Missouri State University] at 07:08 09 February 2015 .57 34.00 3.30 2.00 10.00 .40 1.50 5.00 .70 35.00 .20 8.00 8.00 8.00 2.00 7.00 7.00 2.00 Contr. 5 .50 30.33 3.17 1.33 7.58 .40 .98 8.83 .96 29.08 .37 8.17 8.17 8.17 7.00 8.21 8.21 1.88 Avg. .05 11.25 .10 .89 6.83 .06 .91 4.55 .95 9.18 .38 2.86 2.86 2.86 4.86 5.15 5.15 1.83 SD Severity % 17 Larimer 0 .50 .40 .44 2.50 .50 .50 3.00 1.00 30.00 2.00 Risk name Weather changes Infrastructure deterioration Non-porous HMA surface Excess or high viscosity rejuvenators Cleanness of cover aggregate Binder & cover aggregate quantity calibration Cleaning procedure Excessive aggregate application Insufficient compaction roughness components consideration Leveling courses overruns Table 7. Maintenance risks severity analysis .25 .05 .75 2.00 .28 .20 2.50 .20 2.50 30.00 2.00 Contr.1 .28 .50 .90 3.00 .30 .40 2.00 .50 5.40 1.80 8.50 Contr.2 4.00 .80 .50 4.00 .80 .80 4.00 0.80 4.00 30.00 20.00 Contr.3 Individual Severity Scores % 3.00 1.00 1.00 3.80 1.50 .40 3.00 1.00 3.45 14.00 15.00 Contr.4 Downloaded by [Missouri State University] at 07:08 09 February 2015 2.00 2.00 1.00 2.60 1.00 .50 3.60 1.20 2.00 20.00 17.10 Contr.5 1.59 .81 .76 2.64 1.06 .47 2.60 1.12 3.06 20.97 10.77 Avg. 1.67 .67 .26 1.31 .84 .20 1.26 .99 1.56 11.50 7.77 SD Severity % 18 Table 8. Correlation analysis of significant risk relationships in the construction phase Variable 2 Sig. value Pearson coefficient Paving speed Screed adjustments Screed adjustments Distance to paver % of crushed aggregate mass Stoppage time Paving speed Screed adjustments Insufficient compaction 0 0 0 0 .017 .036 .036 .036 .036 1 1 1 1 .89 .84 .84 .84 .84 Downloaded by [Missouri State University] at 07:08 09 February 2015 Variable 1 Stoppage time Stoppage time Paving speed Compaction speed Voids control Voids control Voids control Voids control Voids control Throughout the Maintenance Phase Price Fluctuations Weather Preventive Maintenance Fog Seals Excess Asphalt Application Non-Porous HMA surface Loose Aggregate on high Vol./ speed roads Excess/high Viscosity rejuvenators Cleanness of cover aggregate Crack Sealing Slurry Seals Rejuvenators Chip Seals/ Surface treatment Use of 1 size cover aggregate Safety issues associated with application Use of natural sands when skid resistance required Binder & cover aggregate quantities method of calibration Cleaning Procedures Compaction by Steel Wheeled roller Excessive Aggregate application Corrective Maintenance Patching Insufficient Compaction Edge Leveling Thin HMA Overlays Temporary repair costs Roughness components consideration Leveling course overruns Performance LCC Typical Construction problems arise from maintaining equipment Crew’s knowledge Uniform Asphalt binder Spray Adjustment of Asphalt binder to aggregate absorption Early Traffic opening Figure 4. RBS for the risks associated with the HMA maintenance phase. Risk Management for Asphalt Road Construction and Maintenance 19 sections due to surface irregularities where the builder must apply more HMA material than estimated. The contractor can avoid or mitigate those risks by designing an overlay thickness that varies depending on the type of roughness components in the road profile and may use milling machines to mill the old road to a lane surface rather than using leveling courses (Roberts, Kandhal, Brown, Lee, & Kennedy, 1996). Downloaded by [Missouri State University] at 07:08 09 February 2015 Conclusions Currently, Design-Bid-Build (DBB) contracts are used extensively in road construction. However, the use of modern delivery systems represented in PBCs introduces a new challenge for contractors in terms of risk allocation due to the increased risks they have to bear for a longer project commitment through warranty and maintenance periods stated in their contracts. For that reason, risk management has never been more important to contractors since they are taking on more responsibilities that can exploit more risks whether by triggering more risks or dealing with more severe ones. This study identified the most significant risks for HMA contractors during construction and maintenance. During the construction phase, it was found that voids control is one of the most significant risks that have an adverse effect and association with: stoppage time, paving speed, screed adjustment and percent of crushed aggregate mass in the construction phase and insufficient compaction in the maintenance phase. This risk can be mitigated and hopefully eliminated by the contractor by enforcing more quality control procedures in their mixing facility which in turn eliminates a series of dependent risks in the paving, compaction, and corrective maintenance processes and makes those risks more controllable, too. Another important finding is that most of the associated significant risks happen in the paving process: stoppage time, paving speed, and screed adjustments which stress the need for a high level of monitoring and control to be applied during this process. For the maintenance phase, it was found that there are two severe and significant risks which are the roughness components consideration and the leveling course overruns. This is due to the fact that the HMA overlay is the most frequent maintenance procedure applied and most of the contractors treat it as a standard thickness that they apply regardless of what triggers these two risks. Close attention to the roughness component coefficient along with the milling process is essential to mitigate and eliminate these two risks. Some of the most severe and significant risks such as weather, risk of innovation, and price fluctuations were excluded from the correlation analysis due to their nature since they are outside the contractor’s influence to control. However, these risks can be mitigated or transferred through other channels like contractual modifications, variation and change orders, or insurance. Most of the contracting agencies and the contract experts have developed many contractual provisions and clauses to avoid these kinds of risks during construction because of their negative effect on both the owner and the contractor. Based on the above discussion, a contractor should be mindful of such contract language in the first place to avoid these uncontrollable risks. Finally, it is worthy to note that most of these risks can be considered long-term risks and that is the main reason behind their effect under performance-based contracts. Their effect will take place in the performance of the road and its condition, especially if there is a warranty period included in the PBC. However, through the data collection efforts, it was noted that only a few contractors are involved or even willing to be involved in projects under performance-based contracts since they are a relatively new type of delivery system where a lot of risks and responsibilities are allocated to the contractor. There are also some limitation on this study represented in the HMA road and highway industry, the Downloaded by [Missouri State University] at 07:08 09 February 2015 20 M. S. Hashem M. Mehany and A. Guggemos contractors, the area of Colorado and the PBC delivery system. Although, those limitations constrict some of the results of this study, it is still a great step towards the addition to the body of knowledge within this new delivery system. There are several areas of continuing research for this study. One of the most important ones is the study of the risk effects on the costs of the projects and specifically the Life Cycle Cost (LCC) of the project since the PBCs specify a construction period along with maintenance or a warranty life for the project. Another area of expansion on this research is the duplication of this research to study other road types such as concrete roads or other delivery systems such Design-Build (DB) or Integrated Project Delivery (IPD). Finally, studying other key risk items such as safety can be very beneficial for all the parties involved since safety does affect time, cost and speaks to the quality of the job from each of the participants (owner, engineer, subcontractor and contractor). However, it will be quite a challenge since it is one of those risks that very hard to quantify accurately because of its high variability between different jobs and contractors. References AGC. (2014). Project delivery systems for construction. Retrieved October 31, 2014, from http:// www.agc.org/cs/cm_atrisk Berdica, K. (2002). An introduction to road vulnerability: What has been done, is done and should be done. Transport Policy, 9(2), 117–127. Bing, L., Akintoye, A., Edwards, P. J., & Hardcastle, C. (2005). The allocation of risk in PPP/PFI construction projects in the UK. International Journal of Project Management, 23(1), 25–35. Creswell, J. W. (2008). Educational research: Planning, conducting, and evaluating quantitative and qualitative research (3rd ed.). Upper Saddle River, NJ: Pearson. CTC. (1999). Construction Contractors’ rank classification. Central tendering committee, Kuwait. Diepenbrock, E. M., Davison, J. C., Lichtig W. A., & Rudolph, S. P. (2002). Risk allocation in the construction projects. Eau Claire, WI: Lorman Education Services. Greene, M. R., Trieschmann, J. S., & Gustavson, S. G. (1991). Risk and insurance (8th ed.). Cincinnati, OH: South-Western College Publishing. Gruneberg, S., Hughes, W., & Ancell, D. (2007). Risk under performance-based contracting in the UK construction sector. Construction Management & Economics, 25(7), 691–699. Hall, M. (2000). Risk management. Computerworld, 34(3), 58. Hartman, F., & Snelgrove, P. (1996). Risk allocation in lump-sum contracts—Concept of latent dispute. Journal of Construction Engineering & Management, 122(3), 291. Hillson, D. A. (2002, October). Using the risk breakdown structure (RBS) to understand risks. Proceedings of the 33rd Annual Project Management Institute Seminars & Symposium (PMI 2002), San Antonio, Texas. Hillson, D. (2003). Research paper: Using a risk breakdown structure in project management. Journal of Facilities Management, 2(1), 85–97. Kartam, N. A., & Kartam, S. A. (2001). Risk and its management in the Kuwaiti construction industry: A contractors’ perspective. International Journal of Project Management, 19(6), 325–335. McMinimee, J. C., Schaftlein, S., Warne, T. R., Detmer, S. S., Lester, M. C., Mrockza, G. F., . . . Yew, C. (2009). Best practices in project delivery management. Lawrencevill, NJ: American Association of State Highway and Transportation Officials. Molenaar, K. R., Ashley, D. B., & Diekmann, J. E. (2006). Guide to risk assessment and allocation for highway construction management. Retrieved May 1, 2014, from http://international.fhwa.dot.gov/riskassess/pl06032.pdf Perera, B., Dhanasinghe, I., & Rameezdeen, R. (2009). Risk management in road construction: The case of Sri Lanka. International Journal of Strategic Property Management, 13(2), 87–102. Downloaded by [Missouri State University] at 07:08 09 February 2015 Risk Management for Asphalt Road Construction and Maintenance 21 PMBOK Guide. (2004). A guide to the project management body of knowledge (4th ed.). Philadelphia: Project Management Institute. Prieto, B. (2012). Comparison of design bid build and design build finance operate maintain project delivery. PM World Journal, I(V). Rao, S., Mallela, J., & Hoffman, G. (2009). Michigan Demonstration Project: Performance contracting for construction on M-115 in Clare County, MI. Retrieved March 1, 2014, from http://www.fhwa.dot.gov/hfl/summary/pdfs/mi_090209.pdf Roberts, F. L., Kandhal, P. S., Brown, E. R., Lee, D., & Kennedy, T. W. (1996). Hot mix asphalt materials, mixtures, mixture design and construction. Lanham, MD: NAPA Education Foundation. Stankevich, N., Qureshi, N., & Queiroz, C. (2005). Performance-based contracting for preservation and improvement of road assets. Washington DC: The World Bank. Tchankova, L. (2002). Risk identification—Basic stage in risk management. Environmental Management and Health, 13(3), 290–297. 22 Risk of investment in Prices fluctuations Bonding capacity Owner delayed payments Weather Emergency repairs Changing mixes Voids control Long term storage Segregation at dumping MTV-availability Stoppage time Paving speed Screed adjustments % of crushed aggregate mass Compaction speed Distance to paver “Go No-Go” approach Valid N (listwise) Table A1. Descriptive statistics 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 N Statistic Appendix SPSS – Statistical Data Output Results RISKS STATISTICAL ANALYSIS 0.43 16 3 0.15 0 0.3 0 3 0 13 0 4 4 4 2 1 1 0 Minimum Statistic 0.57 45 3.3 2.6 19.5 0.5 2.5 15 2.5 39 1 12 12 12 15 15 15 5 Maximum Statistic 2.97 182 19 8 45.5 2.4 5.9 53 5.75 174.5 2.2 49 49 49 42 49.52 49.25 11.25 Sum Statistic Descriptive Statistics 0.495 30.3333 3.1667 1.3333 7.5833 0.4 0.9833 8.83333 0.9583 29.0833 0.3667 8.1667 8.1667 8.1667 7 8.2083 8.2083 1.875 Mean Statistic 0.0493 11.25463 0.10328 0.88638 6.82947 0.06325 0.90646 4.54606 0.94679 9.17833 0.38297 2.85774 2.85774 2.85774 4.85798 5.15368 5.15368 1.82859 Std. Deviation Statistic Downloaded by [Missouri State University] at 07:08 09 February 2015 0.002 126.667 0.011 0.786 46.642 0.004 0.822 20.667 0.896 84.242 0.147 8.167 8.167 8.167 23.6 26.556 26.556 3.344 Variance Statistic 0.409 0.056 −0.666 0.19 0.982 0 0.952 0.09 0.769 −0.466 2.446 −0.25 −0.25 −0.25 0.895 −0.142 −0.142 0.313 Statistic 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 0.845 Std.Error Skewness 23 a a a a a a a a a a a a a a a a Pearson Correl Sig. (2-tailed) Person Correl Sig. (2-tailed) Person Correl Sig. (2-tailed) Person Correl Sig. (2-tailed) Emergency Person Correl repairs Sig. (2-tailed) Changing mixes Pearson Corel Sig. (2-tailed) Voids control Pearson Corel Sig. (2-tailed) Long term Pearson Corel storage Sig. (2-tailed) Segregation at Pearson Corel dumping Sig. (2-tailed) a a a a Prices fluctuations Pearson Correl Sig. (2-tailed) Rist of investment in innovations Prices fluctuations Bonding capacity Owner delayed payments Weather Table A2. Ordinal correlation results Risk of investment in innovations Downloaded by [Missouri State University] at 07:08 09 February 2015 Bonding capacity a a a a a a a a a a Owner delayed payments a a a Weather −0.707 0 0.116 1 0.686 0.086 0.132 0.872 0 −0.35 1 0.492 a a 0.125 0.813 0.125 1 0.813 a a 1 a a a Emergency repairs a a a a a a a a a a Changing mixes Voids control a a a 0.686 0 0.132 1 0.086 −0.35 0.872 0.492 a a a a a Long term storage −0.728 −0.33 0.101 0.519 −0.728 1 0.243 0.101 0.643 −0333 0.243 1 0.519 0.613 a a a 1 −0.707 0.116 0 1 a a a a Segregation at dumping a a a a a a a a a a MTV-availability Stoppage time Paving speed a a a Screed adjustment a a a % of crushed aggregate mass a a a a a a Compaction speed a a a a a a 0.612 0.612 0.612 0.433 0.433 0.433 −0.17 0.196 0.196 0.196 0.391 0.391 0.391 0.745 −0.306−0.306−0.306 0 −0.433−0.433 0.171 0.555 0.555 0.555 1 0.391 0.391 0.745 a a a a a a a a a a Distance to paver (Continued) −0.447−0.577−0.577−0.577 −.816 −0.408−0.408 0.243 0.374 0.23 0.23 0.23 0.047 0.422 0.422 0.643 −0.108 .840∗ .840∗ .840∗ .891∗ 0.297 0.297 −0.65 0.383 0.036 0.036 0.036 0.017 0.568 0.568 0.165 0.447 0.577 0.577 0.577 0.408 .816∗ .816∗ 0.243 0.374 0.23 0.23 0.23 0.422 0.047 0.047 0.643 a a a a a a a a 0.316 0.541 0.158 0.765 a a a a “Go No-Go” approach 24 View publication stats Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) Pearson Corel Sig. (2-tailed) a a a a a a a a a a a a a a a a Risk of investment in innovations a Prices fluctuations a a a a a a a a a a Bonding capacity ∗∗ Correlation significant at the .05 level (2-tailed). Correlation significant at the .01 level (2-tailed). a. Listwise N = 6. ∗ Screed adjustment % of crushed aggregate mass Compaction speed Distance to paver “Go No-Go” approach Paving speed Paving speed MTVavailability Stoppage time Table A2. (Continued) Downloaded by [Missouri State University] at 07:08 09 February 2015 Owner delayed payments 0.158 0.765 −0.31 0.555 −0.31 0.555 −0.31 0.555 −0.31 0.555 0 1 Weather 0.433 −0.43 0.391 0.391 0.433 −0.43 0.391 0.391 −0.171 0.171 0.745 0.745 0.316 0.541 0.612 0.196 0.612 0.196 0.612 0.196 0.612 0.196 0.433 0.391 Emergency repairs a a a a a a a a a Voids control Changing mixes −0.408 0.297 0.422 0.568 −0.408 0.297 0.422 0.568 0.243 −0.647 0.643 0.165 −0.447−0.108 0.374 0.838 −0.577 .840∗ 0.23 0.036 −0.577 .840∗ 0.23 0.036 −0.577 .840∗ 0.23 0.036 −0.577 .840∗ 0.23 0.036 −816∗ .891∗ 0.047 0.017 Long term storage .816∗ 0.047 .816 0.047 0.243 0.643 0.447 0.374 0.577 0.23 0.577 0.23 0.577 0.23 0.577 0.23 0.408 0.422 a a a a a a a a 0.548 0.261 0.548 0.261 0.759 0.08 0 1 0 1 0 1 0 1 0 1 a Segregation at dumping 1 MTV-availability a Screed adjustment Paving speed 0.707 0.116 0.707 0.116 −0.42 0.407 0.707 0.116 0.707 0.116 −0.42 0.407 % of crushed aggregate mass 0 1 0.707 0.116 0.707 0.116 0.707 0.116 0.707 0.116 1 Compaction speed 0.548 0.261 0.707 0.116 0.707 0.116 0.707 0.116 0.707 0.116 0.25 0.633 0.48 0.261 0.707 0.116 0.707 0.116 0.707 0.116 0.707 0.116 0.25 0.633 Distance to paver 0.707 0.25 1 1.000∗∗ 0.116 0.633 0 0.707 0.25 1.000∗∗ 1 0.116 0.633 0 −0.42 −0.594 0.297 0.297 0.407 0.214 0.568 0.568 0 0 1 1 1.000∗∗1.000∗∗ 0 0 1.000∗∗ 1 1.000∗ 0 0 1.000∗∗ 1 1.000∗ 0 0 1.000∗∗1.000∗∗ 1 0 0 0.707 0.707 0.707 0.116 0.116 0.116 Stoppage time 0 1 1 0.297 0.568 0.297 0.568 1 0.759 0.08 −0.42 0.407 −0.42 0.407 −0.42 0.407 −0.42 0.407 −0.59 0.214 “Go No-Go” approach