SECTION 02740 ASPHALT PAVEMENT PART 1 1.01 SECTION INCLUDES A. 1.02 Section 02340 – Fly Ash Stabilization QUALITY ASSURANCE A. Test samples will be taken in the field by the OWNER’s independent testing service. Mix designs and material samples are to be submitted for review at least 4 weeks prior to material placement. All sampling and testing shall be done in accordance with the latest methods of AASHTO, unless otherwise specified. B. When placing the asphalt trench patch, saw cutting of the existing asphalt will not be permitted within the wheel path of a travel lane. All asphalt patches shall conform to the specifications outlined in the City of Fort Collins Design and Construction Standards for Streets of Public Right-of-way, “Construction Details” section. PART 2 2.01 This section covers paving of all new and existing asphalt surfaces. Existing pavement is to be replaced with similar material as herein set forth. RELATED SECTIONS A. 1.03 GENERAL PRODUCTS MATERIALS A. Cationic Emulsified Asphalt: The cationic emulsified asphalt for the tack coat shall be CSS-1h and shall meet the requirements of AASHTO M 208 (ASTM C 2397). B. Aggregate for Hot Plant Mix Bituminous Pavement: 1. Description – The asphaltic concrete surface shall consist of a mineral aggregate, uniformly mixed with asphalt cement. 2. Materials: a. Crushed Gravel: The crushed gravel shall consist of clean, hard, durable particles which have been crushed to the gradations shown in Table 1 (in accordance with the Colorado Department of Transportation Standard Specifications for Road and Bridge Construction). Aggregates for hot plant mix bituminous pavement shall be of uniform quality, composed of clean, hard, durable particles of crushed stone, crushed gravel, natural gravel, or crushed slag. Excess of fine material shall be wasted before crushing. For Gradings S, SX, and SG, a percentage of the aggregate retained on the 4.75 mm. (No. 4) sieve shall have at least two mechanically induced fractured Werner Elem. 02740-1 Asphalt Pavement faces when tested in accordance with Colorado Procedure 45. This percentage will be provided by the ENGINEER OWNER. The angularity of the fine aggregate shall be a minimum of 45.0% when determined according to CP L-5113, Method A. Aggregate samples representing each aggregate stockpile shall be non-plastic if the percent of aggregate passing the Number 4 sieve is greater than or equal to 10 percent by weight of the individual aggregate sample. Plasticity will be determined in accordance with AASHTO 90. Reclaimed material shall be of uniform quality. The maximum size of the reclaimed asphalt pavement shall be 38 mm (1 1/2 inches) prior to introduction into the mixer. The maximum aggregate size contained in the combination of reclaimed asphalt pavement and new aggregate shall not exceed the maximum specified in Table 1. The hot bituminous pavement shall not contain more than 15 percent reclaimed asphalt pavement. The material shall not contain clay balls, vegetable matter, or other deleterious substances. The aggregate for Gradings S, SX, and SG shall have a percentage of wear of 45 or less when tested in accordance with AASHTO T 96. TABLE 1 MASTER RANGE TABLE FOR HOT BITUMINOUS PAVEMENT Sieve Size Percent by Weight Passing Square Mesh Sieves Grading S Grading SG Grading SX 100 100 90 – 100 90 – 100 100 * * 90 – 100 * * * * * * 23 – 49 19 – 45 28 – 58 37.5 mm (1 1/2”) 25.0 mm (1”) 19.0 mm (3/4”) 12.5 mm (1/2”) 9.5 mm (3/8”) 4.75 mm (#4) 2.36 mm (#8) 1.18 mm (#16) * * * 600 m (#30) 300 m (#50) 150 m (#100) 2–8 1–7 2 –10 75 m (#200) * These additional Form 43 Screens will initially be established for the Contractor’s Quality Control Testing using values from the As Used Gradation shown on the Design Mix. The crushed gravel shall show no detrimental amount of stripping when tested as follows: A test sample consisting of the aggregate and bitumen to be used in the paving mixture shall be mixed at the temperature specified herein. The sample shall then be spread in a loose, thin layer and allowed to air-season for 24 hours before testing. A portion of the sample, not over ½ of the capacity of the Werner Elem. 02740-2 Asphalt Pavement jar, shall be placed in a glass jar and completely covered with distilled water. The jar shall be fitted with a tight screw cap and allowed to stand for a period of 24 hours. The jar shall be vigorously shaken for a period of 15 minutes and the sample of the mixture shall then be examined for stripping. If stripping occurs, the aggregate shall be rejected or an approved method of treating shall be specified to change the material from a hydrophilic to a hydrophobic state as directed by the ENGINEER OWNER. Superpave Performance Graded Binders. Superpave Performance Graded Binders shall conform to the requirements listed in Table 2. The oil to be used shall be Performance Graded Binder 64-22. TABLE 2 SUPERPAVE PERFORMANCE GRADED BINDERS Requirement for PG Binder 58-22 58-28 58-34 64-22 64-28 70-28 76-28 AASHTO Test No. 230 230 230 230 230 230 230 T 28 3 3 3 3 3 3 3 TP 48 58 58 58 64 64 70 76 TP 5 - - - - 50 - - T 51 Toughness, joules (inch-lbs) - - - - - - Tenacity, joules (inch-lbs) - - - - - - *CP L2210 *CP L2210 T 240 1.00 1.00 1.00 1.00 1.00 1.00 1.00 T 240 58 58 58 64 64 70 76 TP 5 - - - - - 50 50 *CP L2211 Method A - - - - 20*** - - T 51 Property Original Binder Properties Flash Point Temp., °C, minimum Viscosity at 135 °C, Pa●s, maximum Dynamic Shear, Temp. °C, where G*/Sin δ @ 10 rad/s ≥ 1.00 kPa Ductility, 4 °C (5 cm/min.), cm minimum 12.4 (110) 8.5 (75) RTFO Residue Properties Mass Loss, percent maximum Dynamic Shear, Temp. °C, where G*/Sin δ @ 10 rad/s ≥ 2.20 kPa Elastic Recovery, 25 °C, percent min. Ductility, 4 °C (5 cm/min.), cm minimum PAV Residue Properties, Aging Temperature 100 °C Dynamic Shear, Temp. °C, where G*●Sin δ @ 10 rad/s ≤ 5000 kPa Creep Stiffness, @ 60 s, Test Temperature in °C S, maximum, MPa m-value, minimum **Direct Tension, Temperature in °C, @ 1 mm/min., where failure strain ≥ 1.0 % PP 1 22 19 16 25 22 25 28 TP 5 -12 -18 -24 -12 -18 -18 -18 300 300 300 300 300 300 300 TP 1 0.300 0.300 0.300 0.300 0.300 0.300 0.300 TP 1 -12 -18 -24 -12 -18 -18 -18 TP 3 *Colorado Procedure **Direct tension measurements are required when needed to show conformance to AASHTO MP 1. ***If the PG 64-28 RTFO residue fails the ductility test, the binder will be accepted if the TFO residue (AASHTO T 179) has a ductility of 25 cm or more. Werner Elem. 02740-3 Asphalt Pavement 2.02 PAVING PLANT REQUIREMENT A. Werner Elem. General Requirements: 1. Uniformity: The plants shall be so designed, coordinated and operated as to produce a mixture within the job mix tolerances as covered in paragraph 2.03C under “Preparation and Composition of the Mixture.” 2. Equipment for Preparation of Asphalt: Tanks for storage of asphalt shall be capable of heating the material, under effective and positive control at all times, to temperature requirements set forth in the Specifications. Heating shall be accomplished by steam coils, electricity, or other means such that no flame shall come in contact with the heating tank. A circulating system for the asphalt shall be provided of adequate size to ensure the property and continuous circulation between storage tank and mixer during the entire operating period. All pipelines and fittings shall be steam jacketed or other properly insulated to prevent heat loss. Storage tank capacity shall be sufficient for at least one day’s run. 3. Dryer: A rotary dryer of any satisfactory design for drying and heating the mineral aggregates shall be provided. The dryer shall be capable of drying and heating the mineral aggregate to the temperature requirements set forth in the Specifications. 4. Screens: Plant screens, capable of screening all aggregates to the size required for proportioning, and having normal capacities slightly in excess of the full capacity of the mixer, shall be provided. The mesh of the screens shall be approved by the ENGINEER OWNER before paving operations. 5. Bins: The plant shall include a minimum of 3 dry aggregate storage bins with the total capacity of not less than 3 times the dead load capacity of the mixer. Each bin shall be provided with an overflow pipe that shall be of such size and at such locations as to prevent any backing up of material into other bins. Each bin shall have a suitable convenient means for sampling. The sampling openings shall be subject to the approval of the ENGINEER OWNER. 6. Thermometric Equipment: An armored thermometer reading from 200F to 500F shall be fixed in the asphalt feed line at a suitable location from the discharge valve at the mixer unit. The plant shall be further equipped with an approved dial scale mercury actuated thermometer, an electric pyrometer, or other approved thermometric instrument so placed at the discharge chute of the dryer as to register automatically or indicate the temperature of the heated aggregate. 7. Dust Collectors: When plants are located in any vicinity where dust may be objectionable, or when dust interferes with the efficient operation of the plant, proper housing, mixer covers, dust collecting systems shall be installed. Provision shall be made to waste the material so collected or to return it uniformly to the mixture as the ENGINEER OWNER may direct. 02740-4 Asphalt Pavement 8. B. Safety Equipment: Adequate and safe stairways to the mixer platform and guarded ladders to other plant units shall be placed at all points required for accessibility to all plant operations. All gears, pulleys, chains, sprockets, and other dangerous moving parts shall be thoroughly guarded and protected. Ample and unobstructed passage shall be maintained at all times in and around the truck loading space. This space shall be kept free from drippings from the mixing platform. Special Requirements of Batch Plants: 1. Plant Scale: Scales for any weight box or hopper may be either of the beam or springless dial type and shall be a standard make and design, sensitive to ½ of 1% of the maximum load that may be required. When of the beam type, there shall be a separate beam with telltale indicator for each size aggregate and a tare beam for balancing the hopper. 2. Control of Mixing Time: The plant shall be equipped with an approved means to govern the time of mixing and to maintain it. 3. Weight Box or Hopper: The equipment shall include a means for accurately weighing each bin size to hold a full batch without hand raking or running over. The weight box or hopper shall be supported on fulcrums and knife edges so constructed that they will not be easily thrown out of alignment or adjustment. Gates on both bins and hopper shall be so constructed as to prevent leakage when they are closed. 4. Asphalt Bucket: The asphalt bucket which is used for weighing the asphalt cement shall have sufficient capacity to hold not less than 10% of the weight of aggregate required for one batch. It shall be steam jacketed or equipped with properly insulated electric heat units and shall be suspended on dial scales or beam scales equipped with a telltale indicator so that the tare weight of asphalt cement can be measured accurately to within 2% above or below the weight required. The bucket shall be so arranged that it will deliver the molten asphalt cement in a thin uniform sheet or in multiple streams the full width of the mixer. 5. Mixer Unit: The plant shall include a batch mixer of an approved twin pugmill type or rotary drum type and shall be capable of producing a uniform mixture within the job mix tolerances fixed by these Specifications. It shall have a batch capacity of not less than 2,000 pounds. If of the pugmill type, worn or improper pugmill paddles will not be permitted. A mechanical batch counter shall be installed and shall be so designed as to register upon only the actuation of the asphalt bucket release and to preclude the register of any material through the operation of pulling bins. Werner Elem. 02740-5 Asphalt Pavement C. Special Requirements for Continuous Mixing Plants: 1. Gradation Control Unit: The plant shall include a means of accurately proportioning each bin size of aggregate either by weighing or by volumetric measurement. When gradation control is by volume, the unit shall have an accurately controlled individual gate to form an orifice for volumetrically measuring the material drawn from each respective bin compartment. Indicators shall be provided on each gate to show the gate opening in inches. 2. Weight Calibration or Aggregate Feed: The plant shall include a means for calibration of gate openings by means of weight test samples. The materials fed out of the bins through individual orifices shall be bypassed to a suitable test box, each compartment material confined in a separate box section. The plant shall be equipped to handle conveniently such test samples weighting up to 800 pounds and to weigh them on accurate scales. 3. Synchronization of Aggregate and Asphalt Feed: Satisfactory means shall be provided to afford positive interlocking control between the flow of aggregate from the bins and the flow of asphalt from the meter or other proportioning sources. This control shall be accomplished by interlocking mechanical means or any positive method under the control of the ENGINEER OWNER. 4. Mixer Unit for Continuous Method: The plant shall include a continuous mixer of an approved twin pugmill type, and shall be capable of producing a uniform mixture within the job mix tolerance fixed by these Specifications. The paddles shall be of a type adjustable for angular position on the shafts and reversible to retard the flow of the mix. The mixer shall carry a manufacturer’s plate giving the net volumetric contents of the mixer at the several heights inscribed on a permanent gauge and also giving the rate of feed of aggregate per minute at plant operating speed. Unless otherwise required, determination of mixing time shall be by weight methods under the following formula. The weights shall be determined for the job by tests made by the ENGINEER OWNER. Mixing time in seconds = Pugmill dead capacity in pounds Pugmill output in pounds/seconds The mixing time shall be approved by the ENGINEER OWNER. 2.03 PREPARATION OF MATERIAL A. Preparation of Asphalt Cement: The asphalt cement shall be heated at the paving plant to a temperature not exceeding 325F. The penetration of the asphalt cement shall be maintained within the limits of penetration specified through the period of use. B. Preparation of Mineral Aggregates: The mineral aggregates shall be dried and heated at the paving plant so that when delivered to the mixer, they shall be at as Werner Elem. 02740-6 Asphalt Pavement low a temperature as is consistent with proper mixing and laying, and in no case to exceed 350F. They may be fed simultaneously into the same drier but in all cases, immediately after heating, they shall be screened into three or more bins. The screen sizes shall be approved by the ENGINEER OWNER prior to the start of construction. C. Preparation and Composition of the Mixture: Each size of hot aggregate, the mineral filler and the asphalt cement shall be measured separately and accurately to the proportions in which they are to be mixed. After the hot aggregate and mineral filler have been charged into the mixer and thoroughly mixed as directed by the ENGINEER OWNER, the asphalt cement shall be added and the mixing continued for a period of at least 20 seconds, or longer if necessary, to produce a homogeneous mixture, in which all particles of the mineral aggregates are coated uniformly. The constituents of the surface course shall be combined in such proportions to produce a mixture conforming to the gradations shown in Table 1. All mix furnished for the project shall conform to within the range of tolerances shown in Table 3. TABLE 3 MIX TOLERANCES Bitumen Content Asphalt Recycling Agent Temperature of Mixture When Discharged from Mixer 0.3% 0.2% 10°C 1 Hot Bituminous Pavement Passing the 9.5 mm (3/8 inch) and larger sievers 6% 2 Passing the 4.75 mm (No. 4 and 2.36 mm (No. 8 sieves) 5% 2 Passing the 600 m (No. 30) sieve 4% 2 Passing the 75 m (No. 200) sieve 2% 1 When 100% passing is designated, there shall be no tolerance. When 90-100% passing is designated, 90% shall be the minimum; no tolerance shall be used. 2 These tolerances apply to the Contractor’s Quality Control Testing. 2 Superpave Performance Graded Binders shall conform to the requirements listed in Table 4 at 75 gyrations. Werner Elem. 02740-7 Asphalt Pavement TABLE 4 MIX DESIGN CRITERIA AT OPTIMUM OIL Property Asphalt Content (%) Voids @ N (INI) Voids @ N (DES) Voids @ N (MAX) V.M.A. (%) % Voids Filled Tensile Strength Retention Dry Tensile Strength (psi) Mixing Temperature Compaction Temperature D. PART 3 3.01 3.02 Specification +/-0.3% 11 Min. 3%-5% 2 Min. 14 Min. 65%-78% 80 Min. 30 Min. 325 Deg. F 300 Deg. F Paving Plant Inspection: For the verification of weights or proportions and character of materials and determination of temperatures used in the preparation of the mixture, the ENGINEER OWNER or his authorized representative shall have access at any time to all parts of the paving plant. EXECUTION SURFACE PREPARATION A. All final pavement cuts shall be made in straight lines using saw cut. Initial pavement cuts may be made using wheel cut or other suitable method. B. Prior to placing the prime coat, the base course shall be thoroughly cleaned. Loose material shall be removed from the existing surface as directed by the ENGINEER OWNER. PRIME COAT A. Werner Elem. All previously prepared bases or existing surface shall be primed with a cationic emulsified asphalt in accordance with the requirements of these Specifications, and at the locations that are shown on the Plans or as directed by the ENGINEER OWNER. The prime coat shall be placed by means of an approved pressure distributor. Before application, the asphaltic oil shall be heated as directed by the ENGINEER OWNER. However, it shall not be heated to more than 180F. In general, the rate of application shall be from 0.25 to 0.35 gallons per square yard as directed by the ENGINEER OWNER. The prime coat shall be carefully applied, particularly around curbs and sidewalks. If excessive amounts of curb, sidewalks, or other structures are sprayed with asphaltic oil, they shall be cleaned as directed by the ENGINEER OWNER at the CONTRACTOR’s expense. All vertical contact faces shall be primed by painting with cationic emulsified asphaltic oil. 02740-8 Asphalt Pavement 3.03 ASPHALTIC CONCRETE SURFACE A. Transportation of Mixture: The mixture shall be transported from the paving plant to the work in vehicles equipped with tight metal compartments previously cleaned of all foreign materials. When directed by the ENGINEER OWNER, the compartments shall be sufficiently insulated and each load shall be covered with canvas or other suitable materials of sufficient size to protect it from weather conditions. The inside surface of all vehicle compartments used for hauling mixture must be lightly lubricated with a tin oil or soap solution just before loading, but excess lubricant will not be permitted. No load shall be sent out so late in the day as to interfere with spreading and compacting the mixture during daylight unless artificial light, satisfactory to the ENGINEER, is provided. B. General Conditions: The mixture shall be laid only when the base is dry and only when weather conditions are suitable. The mixture shall be laid when atmospheric temperatures are consistent with the placement temperature limitations as outlined in Table 5. Asphalt shall not be placed when frost exists in the subgrade. Any material laid shall be rolled with pneumatic rollers in addition to the specified rolling, as directed by the ENGINEER OWNER. C. Placing Asphalt Mixture: If traffic is allowed to use the prepared subgrade or sub-base, the subgrade or sub-base shall be checked and corrected as needed immediately ahead of placing bituminous materials. Prior to placement of the bituminous surface, the base shall be cleaned of all dirt or other foreign matter. When the new pavement abuts the old pavement, the Contractor shall cut the old pavement as directed by the Engineer and paint the edge of the pavement with a tack coat. TABLE 5 PLACEMENT TEMPERATURE LIMITATIONS Compacted Layer Thickness, in mm (inches) Minimum Air and Surface Temperature, °C(°F) Top Layer of Payment Note (1) 15 (60) 10 (50) Note (2) 20 (70) 15 (60) Layers Below Top Layer Note (1) 10 (50) 5 (40) Note (2) 15 (60) 10 (50) 25(1) or less >25 to 75 (1 to 3) >75 (3) --0 (30) 5 (40) Notes: Air Temperature is taken in the shade. Surface is defined as the existing base on which the new pavement is to be placed. (1) Temperatures to be used when mix contains unmodified asphalt cement (PG 5828, PG 58-22, PG 64-22). Temperatures to be used with PG 76-28, PG 70-34, PG 64-28 and Pg 58-40. (2) Temperature to be used when mix contains AC-20R [AC-20 (Rubberized)]. The asphaltic pavement shall be placed only when the base is stable and weather conditions are suitable. The asphaltic pavement shall have a density of ninetytwo percent (92%) to ninety-six percent (96%) of the maximum theoretical Werner Elem. 02740-9 Asphalt Pavement density, determined according to Colorado Procedure 51. Field density determinations will be made in accordance with Colorado Procedure 44 or 81. While the surface is being compacted and finished, the Contractor shall carefully trim the outside edges of the pavement to the proper alignment. Unless otherwise permitted by the ENGINEER OWNER, the mixture shall be spread by means of a mechanical self-powered paver, capable of spreading the mixture true to the line, grade, and crown set by the ENGINEER OWNER. Pavers shall be equipped with hoppers and distributing screws of the reversing type to place the mixture evenly in front of adjustable screeds. The mixture shall be dumped in the center of the hoppers and care exercised to avoid overloading and spilling over of the mixture upon the base. Pavers shall operate when laying mixtures at such speed between 10 feet and 20 feet per minute, as may be decided by the ENGINEER OWNER. Pavers shall be equipped with a quick and efficient steering device and shall have forward and reverse speeds of not less than 100 feet per minute. Unless operating on fixed side forms, pavers shall employ mechanical devices such as equalizing runners, straightedge runners, evener arms, or other compensating devices to adjust the grade and confine the edges of the mixture to true lines within the use of stationary side forms. The pavers shall be capable of spreading the mixtures, without segregation, in thickness of from ½ inch to 3 inches, to a maximum width of 10 feet in increments of 1 foot or less and to a minimum width of 8 feet. They shall be equipped with blending or joint leveling devices for smoothing and adjusting all longitudinal joints between adjacent strips of courses of the same thickness. When asphalt concrete pavement thickness in excess of 2 inches is called for, they shall be laid in separate courses of not less than 1 inch or more than 2 inches or as directed by the ENGINEER OWNER. The term “screed” includes a “strike-off” device operating by cutting, crawling, or other practical action which is effective on the mixture at a workable temperature without tearing, shoving, or gouging and which produces a finished surface of the evenness and texture specified. The screed shall be adjustable as to level and shall have an indicating level attached. Longitudinal and transverse joints shall be made in a careful manner. Well bonded and sealed joints are required. If necessary to obtain this result, joints shall be painted with cationic emulsified asphaltic cement. In making the joint along any adjoining edges such as curb, gutter, or an adjoining pavement and after the hot mixture is placed by the finished machine, just enough of the hot material shall be carried back to fill any space left open. This joint shall be properly “set” up with the back of rake at proper height and level to receive the maximum compression under rolling. The work of “setting up” this joint shall be performed always by competent workmen who are capable of making correct, clean, and neat joints. Immediately after any course is screeded, and before roller compaction is started, the surface shall be checked, any inequalities adjusted, all fat, sandy accumulations from the screed removed by a rake or hoe, and all fat spots in any Werner Elem. 02740-10 Asphalt Pavement course removed and replaced with satisfactory material. Irregularities in alignment and grade along the outside edge shall also be corrected by the addition or removal of mixture before the edge is rolled. In narrow, deep, or irregular sections, intersections, turnouts, or driveways where it is impractical to spread and finish the mixtures by machine methods, the CONTRACTOR may used approved spreading equipment or acceptable hand methods as directed by the ENGINEER OWNER. When the mixture is to be spread by hand, upon arrival on the work it shall be dumped upon a steel dump board outside the area on which it is to be spread. Immediately thereafter it shall be distributed into place by means of hot shovels and spread with hot rakes in a loose layer of uniform density and correct depth. Tines of the rakes shall not be less than ½ inch longer than the loose depth of the mixture, and spaces between tines shall not be less than the maximum diameter of aggregate particle except that in no case should the spaces be less than 1 inch. Loads shall not be dumped any faster than can be properly handled by the shovelers. The shovelers shall not distribute the dumped load faster than it can be properly handled by the rakers. The rakers will not be permitted to stand in the hot mixture while raking it, except where necessary to correct errors in the first raking. The raking must be carefully and skillfully done in such a manner that after the first passage of the roller over the raked mixture, a minimum amount of back patching will be required. Placing mixtures shall be as continuous as possible and the roller shall pass over the unprotected edge of the freshly laid mixture only when the laying of this course is to be discontinued for such intervals of time as to permit the mixture to become chilled. D. Joints: Joints between old and new pavements, or between successive days’ work, shall be carefully made in such a manner as to insure a thorough and continuous bond between the old and new surfaces. The edge of the previously laid course shall be cut back to its full depth so as to expose a fresh surface, after which the hot surface mixture shall be placed in contact with it and raked to a proper depth and grade. Hot smoothers or tampers shall be carefully used in such a manner as to heat up the old pavement sufficiently (without burning it) to insure a proper bond. Before placing mixture against them, all contact surfaces of curbs, gutters, headers, manholes, etc., shall be painted with a thin uniform coating of cationic emulsified asphaltic cement. E. Compaction of the Mixture: After spreading, the mixture shall be thoroughly and uniformly compressed by a power-driven roller or rollers, weighing not less than 8 tons, as soon after being spread as it will bear the roller without undue displacement. Delays in rolling freshly spread mixture will not be tolerated. Rolling shall start longitudinally at the sides and shall proceed toward the center of the pavement overlapping on successive trips by at least ½ the width of a rear wheel. Alternate trips of the roller shall be of slightly different lengths. If the width of the pavement permits, it shall, in addition, be rolled at right angles to the center line. Werner Elem. 02740-11 Asphalt Pavement The speed of the roller shall not exceed 3 miles per hour and shall, at all times, be slow enough to avoid displacements of the hot mixture, and any displacement occurring as a result of reversing the direction of the roller, or from any other cause, shall at once be corrected by the use of rakes and of fresh mixture where required. Rolling shall proceed continuously until all roller marks are eliminated. To prevent adhesion of the mixture to the roller, the wheels shall be kept properly moistened, but excess water will not be permitted. The rollers shall be in good condition, capable of reversing without back-lash and shall weight not less than 200 pounds to the inch of tread. They shall be operated by competent and experienced rollermen and must be kept in continuous operation as nearly as practicable in such a manner that all parts of the pavements shall receive substantially equal compression. Along curbs, headers, manholes, and similar structures, and all places not accessible to the roller, thorough compactions must be secured by means of hot tampers and at all contacts of this character, the joints between these structures and the surface mixture must be effectively sealed. The course, after final compaction, shall conform to the following requirements: It shall be smooth and true to the established crown and grade. It shall have the average thickness specified and shall at no point vary more than ¼ inch from the thickness shown on the typical cross-section in the Plans. Any low or defective places shall immediately be remedied by cutting out the course at such spots and replacing it with fresh, hot mixture which shall be immediately compacted to conform with the surrounding area and shall be free from depressions exceeding ¼-inch as measured with a 10-foot straightedge paralleling the centerline of the roadway. After final compaction, the finished surface course shall at no point have a density less than 92% of the maximum density possible to be obtained in a voidless pavement composed of the same materials in like proportions. Density shall be determined from specimens cut from the finished pavement as directed by the ENGINEER OWNER. 3.04 TEMPORARY ASPHALT COLD-PATCH In the event the CONTRACTOR cannot install hot bituminous pavement, for whatever reason, pursuant to the requirements of these documents, he shall install a temporary asphalt cold-patch pursuant to said requirement and subsequently remove said cold-patch and replace with hot bituminous pavement at the earliest possible date. A. Place suitably prepared base course. B. Minimum thickness: 2 inches on 6-1/2 inches of aggregate base course. C. The CONTRACTOR is responsible for maintaining cold-patch. Werner Elem. 02740-12 Asphalt Pavement 3.05 MANHOLE FRAMES AND VALVE BOXES A. Manhole frames and water valve vaults can be completed after paving operation by using “plates.” B. Foreign matter which is introduced into manholes and valve vaults shall be removed immediately to provide free access to the facilities. C. Valve vaults and manhole rings shall be straight and properly aligned. Adjustments to be made with concrete rings and mortar only (maximum tolerance is ¼”). Valve boxes shall be inspected by placing a valve key on the operating nut to assure a proper alignment. END OF SECTION Werner Elem. 02740-13 Asphalt Pavement THIS PAGE INTENTIONALLY LEFT BLANK. Werner Elem. 02740-14 Asphalt Pavement