USACE / NAVFAC / AFCESA / NASA UFGS-32 12 16 (August 2008) --------------------------- Preparing Activity: USACE Superseding UFGS-32 12 16 (April 2006) UNIFIED FACILITIES GUIDE SPECIFICATIONS References are in agreement with UMRL dated January 2009 SECTION 32 12 16 HOT-MIX ASPHALT (HMA) FOR ROADS 08/08 NOTE: This guide specification covers the requirements for hot-mix asphalt (HMA) courses (central-plant hot-mix) for roads. Edit this guide specification for project specific requirements by adding, deleting, or revising text. For bracketed items, choose applicable items(s) or insert appropriate information. Remove information and requirements not required in respective project, whether or not brackets are present. Comments and suggestions on this guide specification are welcome and should be directed to the technical proponent of the specification. A listing of technical proponents, including their organization designation and telephone number, is on the Internet. Recommended changes to a UFGS should be submitted as a Criteria Change Request (CCR). PART 1 GENERAL NOTE: Modifications must be made to this guide specification during conversion to a project specification in accordance with the NOTES which are located throughout the document. These NOTES are instructions to the designer, and will not appear in the project specification. This guide specification only pertains to the hot-mix asphalt aspects of the project and not to any surface preparation requirements dealing with aggregate base courses, milling, or tack and prime coats. Surface preparation requirements should be covered by either including them in this guide specification or by adding pertinent sections to the project documents. This specification utilizes a Quality Assurance and Quality Control (QA/QC) construction management philosophy. Quality Assurance refers to the actions performed by the Government or designated representative to assure the final product meets the job requirements. This specification has been developed for QC testing to be used as a basis of pay. The Government's QA testing should include as a minimum 10% of the QC tests. The specification can be edited to utilize QA testing results (similar to UFGS-32 12 15 HOT-MIX ASPHALT (HMA) FOR AIRFIELDS) in determining the basis for pay. Quality Control refers to the actions of the Contractor to monitor the Contractor's construction and production processes and to correct these processes when out of control. Results of QC testing are reported daily on the process control charts maintained by the Contractor. Quality Control is covered in paragraph CONTRACTOR QUALITY CONTROL. Quality Control also includes the testing for pay and is covered in paragraphs MATERIAL ACCEPTANCE and PERCENT PAYMENT. For projects less than 500 tons, State DOT material's requirements may be specified. Only material requirements may be substituted as an option. The designer should select which DOT mix design is appropriate for the project. Construction procedures and acceptability of work requirements shall stay the same. The lot size should be the entire paving portion of the project. Designer has the option to eliminate submittal requirement for material samples for this size project. For projects requiring 500 tons to 1000 tons this guide may be used "as is". The lot size should contain the entire paving limits. For projects over 1000 tons use this guide as is. Lot size should be specified appropriately. 1.1 UNIT PRICES 1.1.1 Method of Measurement NOTE: This paragraph will be deleted if the project's paving portion of the work is in one lump-sum contract price. Lump-sum contracts should not be used when the job exceeds 1000 metric tons (tons). The amount paid for will be the number of metric short tons of hot-mix asphalt mixture used in the accepted work. Hot-mix asphalt mixture shall be weighed after mixing, and no separate payment will be made for weight of asphalt cement material incorporated herein. 1.1.2 Basis of Payment NOTE: Delete the first paragraph if the asphalt paving will be bid as part of a lump-sum procurement. For lump-sum payment, include prescriptive unit price based on the Government estimate. Delete the second paragraph if the asphalt paving will be bid as unit price item. Lump-sum contracts should not be used when the job exceeds 1000 metric tons (tons). [Quantities of hot-mix asphalt mixtures, determined as specified above, will be paid for at respective contract unit prices or at reduced prices adjusted in accordance with paragraphs MATERIAL ACCEPTANCE and PERCENT PAYMENT. Payment shall constitute full compensation for furnishing all materials, equipment, plant, and tools; and for all labor and other incidentals necessary to complete work required by this section of the specification.] [The measured quantity of hot-mix asphalt will be paid for and included in the lump-sum contract price. Payment shall constitute full compensation for furnishing all materials, equipment, plant, and tools; and for all labor and other incidentals necessary to complete work required by this section of the specification. If less than 100 percent payment is due based on the pay factors stipulated in paragraphs MATERIAL ACCEPTANCE and PERCENT PAYMENT, a unit price of [_____] per metric short ton shall be used for purposes of calculating the payment reduction.] 1.1.3 _{Percent Payment} NOTE: and pay. On critical projects, it is recommended that testing for pay be changed to a QA responsibility and an independent material testing company be hired by the Government to provide the testing for pay.The basis of pay testing program includes material tests to determine laboratory air voids and in-place density, which are needed to determine percent payment. When a lot of material fails to meet the specification requirements for 100 percent pay as outlined in the following paragraphs, that lot shall be removed and replaced, or accepted at a reduced price which will be computed by multiplying the unit price by the lot's pay factor. The lot pay factor is determined by taking the lowest computed pay factor based on either laboratory air voids, in-place density, grade or smoothness (each discussed below). At the end of the project, an average of all lot pay factors will be calculated. If this average lot pay factor equals or exceeds 95.0 percent, and no individual lot has a pay factor less than 75.1 percent, then the percent payment for the entire project will be 100 percent of the unit bid price. If the average lot pay factor is less than 95.0 percent, then each lot will be paid for at the unit price multiplied by the lot's pay factor. For any lots which are less than 2000 metric 2000 short tons, a weighted lot pay factor will be used to calculate the average lot pay factor. 1.1.4 Laboratory Air Voids and Theoretical Maximum Density Laboratory air voids will be calculated by determining the Marshall or Superpave density of each lab compacted specimen using the laboratory-prepared, thoroughly dry method of ASTM D 2726 and determining the theoretical maximum density of every other sublot sample using ASTM D 2041. Laboratory air void calculations for each sublot will use the latest theoretical maximum density values obtained, either for that sublot or the previous sublot. The mean absolute deviation of the four laboratory air void contents (one from each sublot) from the JMF air void content will be evaluated and a pay factor determined from Table 1. All laboratory air void tests will be completed and reported within 24 hours after completion of construction of each lot. 1.1.5 Mean Absolute Deviation An example of the computation of mean absolute deviation for laboratory air voids is as follows: Assume that the laboratory air voids are determined from 4 random samples of a lot (where 3 specimens were compacted from each sample). The average laboratory air voids for each sublot sample are determined to be 3.5, 3.0, 4.0, and 3.7. Assume that the target air voids from the JMF is 4.0. The mean absolute deviation is then: Mean Absolute Deviation = (|3.5 - 4.0| + |3.0 - 4.0| + |4.0 - 4.0| + |3.7 - 4.0|/4 = (0.5 + 1.0 + 0.0 + 0.3)/4 = (1.8)/4 = 0.45 The mean absolute deviation for laboratory air voids is determined to be 0.45. It can be seen from Table 1 that the lot's pay factor based on laboratory air voids, is 100 percent. Table 1.  Pay Factor Based on Laboratory Air Voids Mean Absolute Deviation of Lab Air Voids from JMF     Pay Factor, %                    O.60 or less                            100                    0.61 - 0.80                              98                    0.81 - 1.00                              95                    1.01 - 1.20                              90                    Above 1.20                        reject (0) 1.1.6 In-place Density NOTE: Designer should edit paragraph below if asphalt layers are required to be one inch or less. For determining in-place density, one random core (100 mm 4 inches or 150 mm 6 inches in diameter) will be taken by the Government from the mat (interior of the lane) of each sublot, and one random core will be taken from the joint (immediately over joint) of each sublot. Each random core will be full thickness of the layer being placed. When the random core is less than 25 mm 1 inch thick, it will not be included in the analysis. In this case, another random core will be taken. After air drying to a constant weight, cores obtained from the mat and from the joints will be used for in-place density determination. 1.1.7 Mat and Joint Densities The average in-place mat and joint densities are expressed as a percentage of the average TMD for the lot. The TMD for each lot will be determined as the average TMD of the two random samples per lot. The average in-place mat density and joint density for a lot are determined and compared with Table 2 to calculate a single pay factor per lot based on in-place density, as described below. First, a pay factor for both mat density and joint density are determined from Table 2. The area associated with the joint is then determined and will be considered to be 1.5 m 5 feet wide times the length of completed longitudinal construction joint in the lot. This area will not exceed the total lot size. The length of joint to be considered will be that length where a new lane has been placed against an adjacent lane of hot-mix asphalt pavement, either an adjacent freshly paved lane or one paved at any time previously. The area associated with the joint is expressed as a percentage of the total lot area. A weighted pay factor for the joint is determined based on this percentage (see example below). The pay factor for mat density and the weighted pay factor for joint density is compared and the lowest selected. This selected pay factor is the pay factor based on density for the lot. When the TMD on both sides of a longitudinal joint is different, the average of these two TMD will be used as the TMD needed to calculate the percent joint density. All density results for a lot will be completed and reported within 24 hours after the construction of that lot. Table 2.  Pay Factor Based on In-place Density Average Mat Density                            Average Joint Density        (4 Cores)            Pay Factor, %               (4 Cores)   --------------------------------------------------------------------   94.0 or 96.0                   100.0                 92.5 or above      93 9                        100.0                     92.4   93.8 or 96.1                    99.9                     92.3      93.7                         99.8                     92.2   93.6 or 96.2                    99.6                     92.1      93.5                         99.4                     92.0   93.4 or 96.3                    99.1                     91.9      93.3                         98.7                     91.8   93.2 or 96.4                    98.3                     91.7      93.1                         97.8                     91.6   93.0 or 96.5                    97.3                     91.5      92.9                         96.3                     91.4   92.8 or 96.6                    94.1                     91.3      92.7                         92.2                     91.2   92.6 or 96.7                    90.3                     91.1      92.5                         87.9                     91.0   92.4 or 96.8                    85.7                     90.9      92.3                         83.3                     90.8   92.2 or 96.9                    80.6                     90.7      92.1                         78.0                     90.6   92.0 or 97.0                    75.0                     90.5   below 92.0 or above 97.0         0.0 (reject)      below 90.5 1.1.8 Pay Factor Based on In-place Density An example of the computation of a pay factor (in I-P units only) based on in-place density, is as follows: Assume the following test results for field density made on the lot: (1) Average mat density = 93.2 percent of TMD. (2) Average joint density = 91.5 percent of TMD. (3) Total area of lot = 30,000 square feet. (4) Length of completed longitudinal construction joint = 2000 feet. a. Step 1: Determine pay factor based on mat density and on joint density, using Table 2: Mat density of 93.2 percent = 98.3 pay factor. Joint density of 91.5 percent = 97.3 pay factor. b. Step 2: Determine ratio of joint area (length of longitudinal joint x 5 ft) to mat area (total paved area in the lot): Multiply the length of completed longitudinal construction joint by the specified 5 ft. width and divide by the mat area (total paved area in the lot). (2000 ft. x 5 ft.)/30000 sq.ft. = 0.3333 ratio of joint area to mat area (ratio). c. Step 3: Weighted pay factor (wpf) for joint is determined as indicated below: wpf = joint pay factor + (100 - joint pay factor) (1 - ratio) wpf = 97.3 + (100-97.3) (1-.3333) = 99.1% d. Step 4: Compare weighted pay factor for joint density to pay factor for mat density and select the smaller: Pay factor for mat density: 98.3%. Weighted pay factor for joint density: 99.1% Select the smaller of the two values as pay factor based on density: 98.3% 1.1.9 Pay Factor for Grade When more than 5 percent of all measurements made within a lot are outside the 15 mm 0.05 foot tolerance, the pay factor based on grade for that lot will be 95 percent. In areas where the grade exceeds the tolerance by more than 50 percent, the Contractor shall remove the surface lift full depth; the Contractor shall then replace the lift with hot-mix asphalt to meet specification requirements, at no additional cost to the Government. 1.1.10 Payment Adjustment for Smoothness a. Straightedge Testing. Location and deviation from straightedge for all measurements shall be recorded. When between 5.0 and 10.0 percent of all measurements made within a lot exceed the tolerance specified in paragraph Smoothness Requirements above, after any reduction of high spots or removal and replacement, the computed pay factor for that lot based on surface smoothness, will be 95 percent. When more than 10.0 percent of all measurements exceed the tolerance, the computed pay factor will be 90 percent. When between 15.0 and 20.0 percent of all measurements exceed the tolerance, the computed pay factor will be 75 percent. When 20.0 percent or more of the measurements exceed the tolerance, the lot shall be removed and replaced at no additional cost to the Government. Regardless of the above, any small individual area with surface deviation which exceeds the tolerance given above by more than 50 percent, shall be corrected by diamond grinding to meet the specification requirements above or shall be removed and replaced at no additional cost to the Government. b. Profilograph Testing. Location and data from all profilograph measurements shall be recorded. When the Profile Index of a 0.1 km 0.1 mile segment of a lot exceeds the tolerance specified in paragraph Smoothness Requirements above by 16 mm/km 1.0 inch/mile, but less than 32 mm/km 2.0 inches/mile, after any reduction of high spots or removal and replacement, the computed pay factor for that lot based on surface smoothness will be 95 percent. When the Profile Index exceeds the tolerance by 32 mm/km 2.0 inches/mile, but less than 47 mm/km 3.0 inches/mile, the computed pay factor will be 90 percent. When the Profile Index exceeds the tolerance by 47 mm/km 3.0 inches/mile, but less than 63 mm/km 4.0 inches/mile , the computed pay factor will be 75 percent. When the Profile Index exceeds the tolerance by 63 mm/km 4.0 inches/mile or more, the lot shall be removed and replaced at no additional cost to the Government. Regardless of the above, any small individual area with surface deviation which exceeds the tolerance given above by more than 79 mm/km 5.0 inches/mile or more, shall be corrected by grinding to meet the specification requirements above or shall be removed and replaced at no additional cost to the Government. c. Bumps ("Must Grind" Areas). Any bumps ("must grind" areas) shown on the profilograph trace which exceed 7.5 mm 0.3 inch in height shall be reduced by diamond grinding until they do not exceed 7.5 mm 0.3 inch when retested. Such grinding shall be tapered in all directions to provide smooth transitions to areas not requiring grinding. The following will not be permitted: (1) skin patching for correcting low areas, (2) planing or milling for correcting high areas. At the Contractor's option, pavement areas, including ground areas, may be rechecked with the profilograph in order to record a lower Profile Index. 1.2 REFERENCES NOTE: This paragraph is used to list the publications cited in the text of the guide specification. The publications are referred to in the text by basic designation only and listed in this paragraph by organization, designation, date, and title. Use the Reference Wizard's Check Reference feature when you add a RID outside of the Section's Reference Article to automatically place the reference in the Reference Article. Also use the Reference Wizard's Check Reference feature to update the issue dates. References not used in the text will automatically be deleted from this section of the project specification when you choose to reconcile references in the publish print process. The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only. AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS (AASHTO)AASHTO M 320(2005) Performance-Graded Asphalt BinderASPHALT INSTITUTE (AI)AI MS-02(6th Edition; 1997) Mix Design Methods for AsphaltAI MS-22(2nd Edition; 2001) Construction of Hot-Mix Asphalt PavementsAI SP-2(2001e3) Superpave Mix DesignASTM INTERNATIONAL (ASTM)ASTM C 117(2004) Standard Test Method for Materials Finer than 75-um (No. 200) Sieve in Mineral Aggregates by WashingASTM C 1252(2006) Standard Test Methods for Uncompacted Void Content of Fine Aggregate (as Influenced by Particle Shape, Surface Texture, and Grading)ASTM C 131(2006)Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles MachineASTM C 136(2006) Standard Test Method for Sieve Analysis of Fine and Coarse AggregatesASTM C 142(1997; R 2004) Standard Test Method for Clay Lumps and Friable Particles in AggregatesASTM C 29/C 29M(2007) Standard Test Method for Bulk Density ("Unit Weight") and Voids in AggregateASTM C 566(1997; R 2004) Standard Test Method for Total Evaporable Moisture Content of Aggregate by DryingASTM C 88(2005) Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or Magnesium SulfateASTM D 140(2001; R 2007) Sampling Bituminous MaterialsASTM D 1461(1985; R 2006) Moisture or Volatile Distillates in Bituminous Paving MixturesASTM D 2041(2003a) Theoretical Maximum Specific Gravity and Density of Bituminous Paving MixturesASTM D 2172(2005) Quantitative Extraction of Bitumen from Bituminous Paving MixturesASTM D 2419(2002) Sand Equivalent Value of Soils and Fine AggregateASTM D 242(2004) Mineral Filler for Bituminous Paving MixturesASTM D 2489/D 2489M(2008) Estimating Degree of Particle Coating of Bituminous-Aggregate MixturesASTM D 2726(2008) Bulk Specific Gravity and Density of Non-Absorptive Compacted Bituminous MixturesASTM D 2950(2005) Density of Bituminous Concrete in Place by Nuclear MethodsASTM D 3381(2005) Viscosity-Graded Asphalt Cement for Use in Pavement ConstructionASTM D 3665(2007) Random Sampling of Construction MaterialsASTM D 3666(2007e1) Minimum Requirements for Agencies Testing and Inspecting Road and Paving MaterialsASTM D 4125(2005) Asphalt Content of Bituminous Mixtures by the Nuclear MethodASTM D 4791(2005e1) Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse AggregateASTM D 4867/D 4867M(2004) Effect of Moisture on Asphalt Concrete Paving MixturesASTM D 5444(2008) Mechanical Size Analysis of Extracted AggregateASTM D 6307(2005) Asphalt Content of Hot Mix Asphalt by Ignition MethodASTM D 6926(2004) Preparation of Bituminous Specimens Using Marshall ApparatusASTM D 6927(2006) Standard Test Method for Marshall Stability and Flow of Bituminous MixturesASTM D 946(1982; R 2005) Penetration-Graded Asphalt Cement for Use in Pavement ConstructionASTM D 995(1995b; R 2002) Mixing Plants for Hot-Mixed, Hot-Laid Bituminous Paving MixturesSTATE OF CALIFORNIA DEPARTMENT OF TRANSPORTATION (CDT)CDT Test 526(2002) Operation of California Profilograph and Evaluation of ProfilesU.S. ARMY CORPS OF ENGINEERS (USACE)COE CRD-C 171(1994) Standard Test Method for Determining Percentage of Crushed Particles in Aggregate1.3 SYSTEM DESCRIPTION The work shall consist of pavement courses composed of mineral aggregate and asphalt material heated and mixed in a central mixing plant and placed on a prepared course. HMA designed and constructed in accordance with this section shall conform to the lines, grades, thicknesses, and typical cross sections shown on the drawings. Each course shall be constructed to the depth, section, or elevation required by the drawings and shall be rolled, finished, and approved before the placement of the next course. 1.3.1 Asphalt Mixing Plant Plants used for the preparation of hot-mix asphalt shall conform to the requirements of ASTM D 995 with the following changes: a. Truck Scales. The asphalt mixture shall be weighed on approved certified scales at the Contractor's expense. Scales shall be inspected and sealed at least annually by an approved calibration laboratory. b. Testing Facilities. The Contractor shall provide laboratory facilities at the plant for the use of the Government's acceptance testing and the Contractor's quality control testing. c. Inspection of Plant. The Contracting Officer shall have access at all times, to all areas of the plant for checking adequacy of equipment; inspecting operation of the plant; verifying weights, proportions, and material properties; checking the temperatures maintained in the preparation of the mixtures and for taking samples. The Contractor shall provide assistance as requested, for the Government to procure any desired samples. d. Storage Bins. Use of storage bins for temporary storage of hot-mix asphalt will be permitted as follows: (1) The asphalt mixture may be stored in non-insulated storage bins for a period of time not exceeding 3 hours. (2) The asphalt mixture may be stored in insulated storage bins for a period of time not exceeding 8 hours. The mix drawn from bins shall meet the same requirements as mix loaded directly into trucks. 1.3.2 Hauling Equipment Trucks used for hauling hot-mix asphalt shall have tight, clean, and smooth metal beds. To prevent the mixture from adhering to them, the truck beds shall be lightly coated with a minimum amount of paraffin oil, lime solution, or other approved material. Petroleum based products shall not be used as a release agent. Each truck shall have a suitable cover to protect the mixture from adverse weather. When necessary to ensure that the mixture will be delivered to the site at the specified temperature, truck beds shall be insulated or heated and covers (tarps) shall be securely fastened. 1.3.3 Asphalt Pavers Asphalt pavers shall be self-propelled, with an activated screed, heated as necessary, and shall be capable of spreading and finishing courses of hot-mix asphalt which will meet the specified thickness, smoothness, and grade. The paver shall have sufficient power to propel itself and the hauling equipment without adversely affecting the finished surface. 1.3.3.1 Receiving Hopper The paver shall have a receiving hopper of sufficient capacity to permit a uniform spreading operation. The hopper shall be equipped with a distribution system to place the mixture uniformly in front of the screed without segregation. The screed shall effectively produce a finished surface of the required evenness and texture without tearing, shoving, or gouging the mixture. 1.3.3.2 Automatic Grade Controls NOTE: Delete information on automatic grade control if not needed. Automatic grade control is needed when the design requires elevations for the hot-mix asphalt surface. If an automatic grade control device is used, the paver shall be equipped with a control system capable of automatically maintaining the specified screed elevation. The control system shall be automatically actuated from either a reference line and/or through a system of mechanical sensors or sensor-directed mechanisms or devices which will maintain the paver screed at a predetermined transverse slope and at the proper elevation to obtain the required surface. The transverse slope controller shall be capable of maintaining the screed at the desired slope within plus or minus 0.1 percent. A transverse slope controller shall not be used to control grade. The controls shall be capable of working in conjunction with any of the following attachments: a. Ski-type device of not less than 9.14 m 30 feet in length. b. Taut stringline set to grade. c. Short ski or shoe for joint matching. d. Laser control. 1.3.4 Rollers Rollers shall be in good condition and shall be operated at slow speeds to avoid displacement of the asphalt mixture. The number, type, and weight of rollers shall be sufficient to compact the mixture to the required density while it is still in a workable condition. Equipment which causes excessive crushing of the aggregate shall not be used. 1.4 SUBMITTALS NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL PROCEDURES and edit the following list to reflect only the submittals required for the project. Submittals should be kept to the minimum required for adequate quality control. A “G” following a submittal item indicates that the submittal requires Government approval. Some submittals are already marked with a “G”. Only delete an existing “G” if the submittal item is not complex and can be reviewed through the Contractor’s Quality Control system. Only add a “G” if the submittal is sufficiently important or complex in context of the project. For submittals requiring Government approval on Army projects, a code of up to three characters within the submittal tags may be used following the "G" designation to indicate the approving authority. Codes for Army projects using the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO" for District Office (Engineering Division or other organization in the District Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project Office. Codes following the "G" typically are not used for Navy, Air Force, and NASA projects. Choose the first bracketed item for Navy, Air Force and NASA projects, or choose the second bracketed item for Army projects. Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for [Contractor Quality Control approval.] [information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government.] Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES: _{SD-03 Product Data Mix Design}[; _G][; _{G, [_____]}] Proposed JMF. _{Contractor Quality Control}[; _G][; _{G, [_____]}] Quality control plan. _{Material Acceptance}[; _G][; _{G, [_____]}] Acceptance test results. _{Percent Payment}[; _G][; _{G, [_____]}] Pay calculations. _{SD-04 Samples Asphalt Cement Binder} A 20 L 5 gallon sample for mix design verification. _Aggregates Sufficient materials to produce 90 kg 200 lb of blended mixture for mix design verification. _{SD-06 Test Reports Aggregates}[; _G][; _{G, [_____]}] _{QC Monitoring} Aggregate and QC test results. _{SD-07 Certificates Asphalt Cement Binder}[; _G][; _{G, [_____]}] Copies of certified test data. Amount, type and description of any modifiers blended into the asphalt cement binder _{Testing Laboratory} Certification of compliance. Plant Scale Calibration Certification 1.5 ENVIRONMENTAL REQUIRENMENTS The hot-mix asphalt shall not be placed upon a wet surface or when the surface temperature of the underlying course is less than specified in Table 3. The temperature requirements may be waived by the Contracting Officer, if requested; however, all other requirements, including compaction, shall be met. Table 3.  Surface Temperature Limitations of Underlying Course                Mat Thickness, mm                        Degrees C                  75 or greater                              4                  Less than 75                               7 Table 3.  Surface Temperature Limitations of Underlying Course                Mat Thickness, inches                    Degrees F                  3 or greater                              40                  Less than 3                               45 PART 2 PRODUCTS 2.1 _AGGREGATES Aggregates shall consist of crushed stone, crushed gravel, crushed slag, screenings, natural sand and mineral filler, as required. The portion of material retained on the 4.75 mm No. 4 sieve is coarse aggregate. The portion of material passing the 4.75 mm No. 4 sieve and retained on the 0.075 mm No. 200 sieve is fine aggregate. The portion passing the 0.075 mm No. 200 sieve is defined as mineral filler. All aggregate test results and samples shall be submitted to the Contracting Officer at least 14 days prior to start of construction. 2.1.1 Coarse Aggregate NOTE: The requirement for magnesium sulfate or sodium (requirement b., below) may be deleted in climates where freeze-thaw does not occur. However, in these areas where freeze-thaw does not occur, requirement b., should remain if experience has shown that this test separates good performing aggregates from bad performing aggregates. Coarse aggregate shall consist of sound, tough, durable particles, free from films of material that would prevent thorough coating and bonding with the asphalt material and free from organic matter and other deleterious substances. All individual coarse aggregate sources shall meet the following requirements: a. The percentage of loss shall not be greater than 40 percent after 500 revolutions when tested in accordance with ASTM C 131. b. The percentage of loss shall not be greater than 18 percent after five cycles when tested in accordance with ASTM C 88 using magnesium sulfate [or 12 percent when using sodium sulfate]. c. At least 75 percent by weight of coarse aggregate shall have at least two or more fractured faces when tested in accordance with COE CRD-C 171. Fractured faces shall be produced by crushing. d. The particle shape shall be essentially cubical and the aggregate shall not contain more than 20% percent, by weight, of flat and elongated particles (3:1 ratio of maximum to minimum) when tested in accordance with ASTM D 4791. e. Slag shall be air-cooled, blast furnace slag, and shall have a compacted weight of not less than 1200 kg/cubic meter 75 lb/cu ft when tested in accordance with ASTM C 29/C 29M. f. Clay lumps and friable particles shall not exceed 0.3 percent, by weight, when tested in accordance with ASTM C 142. 2.1.2 Fine Aggregate NOTE: The lower limit for uncompacted void content (requirement b., below) should be set at 45 for fine aggregate angularity unless local experiences indicate that a lower value can be used. There are some aggregates which have a good performance record and have an uncompacted void content less than 45. In no case should the limit be set less than 43. Fine aggregate shall consist of clean, sound, tough, durable particles. The aggregate particles shall be free from coatings of clay, silt, or any objectionable material and shall contain no clay balls. a. All individual fine aggregate sources shall have a sand equivalent value not less than 45 when tested in accordance with ASTM D 2419. b. The fine aggregate portion of the blended aggregate shall have an uncompacted void content not less than 45.0 percent when tested in accordance with ASTM C 1252 Method A. c. The quantity of natural sand (noncrushed material) added to the aggregate blend shall not exceed 25 percent by weight of total aggregate. d. Clay lumps and friable particles shall not exceed 0.3 percent, by weight, when tested in accordance with ASTM C 142 2.1.3 Mineral Filler Mineral filler shall be nonplastic material meeting the requirements of ASTM D 242. 2.1.4 Aggregate Gradation NOTE: Delete from Table 4, the gradations that will not be used as a part of this project. Generally, the layer thickness should be at least 57 mm (2.25 inches) for gradation 1, 37 mm (1.5 inches) for gradation 2, and 28 mm (1 inch) for gradation 3 shown in Table 4. The combined aggregate gradation shall conform to gradations specified in Table 2, when tested in accordance with ASTM C 136 and ASTM C 117, and shall not vary from the low limit on one sieve to the high limit on the adjacent sieve or vice versa, but grade uniformly from coarse to fine. Table 4.  Aggregate Gradations                     Gradation 1      Gradation 2      Gradation 3                    Percent Passing  Percent Passing  Percent Passing   Sieve Size, mm      by Mass          by Mass                 25.0              100               ---               ---       19.0             76-96              100               ---       12.5             68-88             76-96              100        9.5             60-82             69-89             76-96        4.75            45-67             53-73             58-78        2.36            32-54             38-60             40-60        1.18            22-44             26-48             28-48        0.60            15-35             18-38             18-38        0.30             9-25             11-27             11-27        0.15             6-18              6-18              6-18        0.075            3-6               3-6               3-6 Table 4.  Aggregate Gradations                        Gradation 1       Gradation 2       Gradation 3                        Percent Passing   Percent Passing   Percent Passing   Sieve Size, inch      by Mass            by Mass           by Mass       1                 100               ---               ---       3/4              76-96              100               ---       1/2              68-88             76-96              100       3/8              60-82             69-89             76-96      No. 4             45-67             53-73             58-78      No. 8             32-54             38-60             40-60      No. 16            22-44             26-48             28-48      No. 30            15-35             18-38             18-38      No. 50             9-25             11-27             11-27      No. 100            6-18              6-18              6-18      No. 200            3-6               3-6               3-6 2.2 _{ASPHALT CEMENT BINDER} NOTE: Performance Grade (PG) asphalt should be specified wherever available. When selecting PG asphalt cements, it is recommended that 98 percent reliability be used. For Design Indexes (DI) of 3 and below use a 50% reliability. Also, consider local experience of State Department of Transportation and availability of desired asphalt grade. Asphalt cement binder shall conform to AASHTO M 320 Performance Grade (PG) [_____]. [As an alternate, ASTM D 3381 Table 4, Viscosity Grade [_____] or ASTM D 946 penetration grade [_____] may be used.] Test data indicating grade certification shall be provided by the supplier at the time of delivery of each load to the mix plant. Copies of these certifications shall be submitted to the Contracting Officer. The supplier is defined as the last source of any modification to the binder. The Contracting Officer may sample and test the binder at the mix plant at any time before or during mix production. Samples for this verification testing shall be obtained by the Contractor in accordance with ASTM D 140 and in the presence of the Contracting Officer. These samples shall be furnished to the Contracting Officer for the verification testing, which shall be at no cost to the Contractor. Samples of the asphalt cement specified shall be submitted for approval not less than 14 days before start of the test section. 2.3 _{MIX DESIGN} NOTE: For state DOT Superpave mixes, specify the design EASLs from site-specific traffic studies or the following: Design EASLs (millions) Typical Roadway Application < 0.3 Very light traffic; no trucks (local/county roads, city streets) 0.3 to < 3 Medium traffic (collector roads, most county roads) 3 to 30 High traffic (most of interstate system, climbing lanes, truck weigh stations) Specify the nominal maximum aggregate size (NMAS) in accordance with state DOT guidance. a. The Contractor shall develop the mix design. The asphalt mix shall be composed of a mixture of well-graded aggregate, mineral filler if required, and asphalt material. The aggregate fractions shall be sized, handled in separate size groups, and combined in such proportions that the resulting mixture meets the grading requirements of the job mix formula (JMF). No hot-mix asphalt for payment shall be produced until a JMF has been approved. The hot-mix asphalt shall be designed using procedures contained in AI MS-02 and the criteria shown in Table 5. The hand-held hammer shall be used to compact the specimens. If the Tensile Strength Ratio (TSR) of the composite mixture, as determined by ASTM D 4867/D 4867M is less than 75, the aggregates shall be rejected or the asphalt mixture treated with an approved anti-stripping agent. The amount of anti-stripping agent added shall be sufficient to produce a TSR of not less than 75. If an antistrip agent is required, it shall be provided by the Contractor at no additional cost. Sufficient materials to produce 90 kg 200 pound of blended mixture shall be provided to the Contracting Officer for verification of mix design at least 14 days prior to construction of test section. b. At the option of the Contractor a currently used DOT Superpave hot mix may be used in lieu of developing a Marshall hot mix design as described herein. The Superpave volumetric mix shall be designed in accordance with AI SP-2. The nominal maximum aggregate size (NMAS) shall be [37.5] [25.0] [19.0] [12.5] [9.5] mm [1-1/2] [1] [3/4] [1/2] [3/8] inch. Other DOT hot mix design methods (Hveem, etc.) may be suitable, as determined by the Contracting Officer. The number of compaction gyrations, Ndes, shall be based on a design traffic of [_____] equivalent single axle loads (EASLs). 2.3.1 JMF Requirements NOTE: In Table 5, use a 75 Blow (compactive effort) Marshall Mix for all pavements designed for tire pressures of 690 kPa (100 psi) or higher. For pavements designed for tire pressures less than 690 kPa (100 psi), use a 50 Blow Mix. Also, use a 50 Blow Mix for shoulder pavements. In Table 5, delete the column which does not apply, unless the project includes both 75 Blow and 50 Blow mixes. If both mixes are used on a project, identify which mix is applicable to which location. Select the appropriate gradation and VMA requirements in Table 5 to be consistent with the gradation chosen in Table 4 and delete the other two lines. Remove item t., below if RAP is not used in the job. The job mix formula shall be submitted in writing by the Contractor for approval at least 14 days prior to the start of the test section and shall include as a minimum: a. Percent passing each sieve size. b. Percent of asphalt cement. c. Percent of each aggregate and mineral filler to be used. d. Asphalt viscosity grade, penetration grade, or performance grade. e. Number of blows of hand-held hammer per side of molded specimen. f. Laboratory mixing temperature. g. Lab compaction temperature. h. Temperature-viscosity relationship of the asphalt cement. i. Plot of the combined gradation on the 0.45 power gradation chart, stating the nominal maximum size. j. Graphical plots of stability, flow, air voids, voids in the mineral aggregate, and unit weight versus asphalt content as shown in AI MS-02. k. Specific gravity and absorption of each aggregate. l. Percent natural sand. m. Percent particles with 2 or more fractured faces (in coarse aggregate). n. Fine aggregate angularity. o. Percent flat or elongated particles (in coarse aggregate). p. Tensile Strength Ratio(TSR). q. Antistrip agent (if required) and amount. r. List of all modifiers and amount. s. Correlation of hand-held hammer with mechanical hammer. t. Percentage and properties (asphalt content, binder properties, and aggregate properties) of reclaimed asphalt pavement (RAP) in accordance with paragraph RECYCLED HOT-MIX ASPHALT, if RAP is used. Table 5.  Marshall Design Criteria         Test Property          50 Blow Mix            75 Blow Mix      Stability, newtons      minimum                      *4450                  *8000      Flow, 0.25 mm                 8-18                   8-16      Air voids, percent            3-5                    3-5      Percent Voids in      mineral aggregate (VMA),      (minimum)                           Gradation 1                13.0                  13.0          Gradation 2                14.0                  14.0          Gradation 3                15.0                  15.0      TSR, minimum percent           75                     75 Table 5.  Marshall Design Criteria         Test Property          50 Blow Mix            75 Blow Mix      Stability, pounds      minimum                      *1000                  *1800      Flow, 0.01 inch               8-18                   8-16      Air voids, percent            3-5                     3-5      Percent Voids in      mineral aggregate VMA,      (minimum)                           Gradation 1               13.0                   13.0          Gradation 2               14.0                   14.0          Gradation 3               15.0                   15.0      TSR, minimum percent           75                     75 * This is a minimum requirement. The average during construction shall be significantly higher than this number to ensure compliance with the specifications. ** Calculate VMA in accordance with AI MS-02, based on ASTM D 2726 bulk specific gravity for the aggregate. 2.3.2 Adjustments to Field JMF The Laboratory JMF for each mixture shall be in effect until a new formula is approved in writing by the Contracting Officer. Should a change in sources of any materials be made, a new laboratory jmf design shall be performed and a new JMF approved before the new material is used. The Contractor will be allowed to adjust the Laboratory JMF within the limits specified below to optimize mix volumetric properties with the approval of the Contracting Officer. Adjustments to the Laboratory JMF shall be applied to the field (plant) established JMF and limited to those values as shown. Adjustments shall be targeted to produce or nearly produce 4 percent voids total mix (VTM). TABLE 6. Field (Plant) Established JMF Tolerances Sieves         Adjustments (plus or minus), percent             12.5 mm                     3             4.75 mm                     3             2.36 mm                     3             0.075 mm                    1             Binder Content              0.4 TABLE 6. Field (Plant) Established JMF Tolerances Sieves         Adjustments (plus or minus), percent             1/2 inch                    3             No. 4                       3             No. 8                       3             No. 200                     1             Binder Content              0.40 If adjustments are needed that exceed these limits, a new mix design shall be developed. Tolerances given above may permit the aggregate grading to be outside the limits shown in Table 4; while not desirable, this is acceptable, except for the 0.075 mm No. 200 sieve, which shall remain within the aggregate grading of Table 4. 2.4 RECYCLED HOT MIX ASPHALT NOTE: Reclaimed Asphalt Pavement (RAP)can be used up to 30% as long as the resulting recycled mix meets all requirements that are specified for virgin mixtures. The 30% is a general limit. If the existing asphalt pavement is relatively old, the amount of RAP used will not approach this limit. If the recycling involves relatively new RAP materials, the percentage of RAP specified below could be greater than 30%. Remove these paragraphs if RAP is not used. In addition to MS-02, refer to UFC 3-250-03, "Standard Practice Manual for Flexible Pavements" for further design guidance. Recycled HMA shall consist of reclaimed asphalt pavement (RAP), coarse aggregate, fine aggregate, mineral filler, and asphalt cement. The RAP shall be of a consistent gradation and asphalt content and properties. When RAP is fed into the plant, the maximum RAP chunk size shall not exceed 50 mm 2 inches. The recycled HMA mix shall be designed using procedures contained in AI MS-02 and AI MS-22. The job mix shall meet the requirements of paragraph MIX DESIGN. The amount of RAP shall not exceed 30 percent. 2.4.1 RAP Aggregates and Asphalt Cement The blend of aggregates used in the recycled mix shall meet the requirements of paragraph AGGREGATES. The percentage of asphalt in the RAP shall be established for the mixture design according to ASTM D 2172 using the appropriate dust correction procedure. 2.4.2 RAP Mix NOTE: The appropriate test should be selected to conform to the grade of new asphalt specified. If a PG grade is specified, use the dynamic shear rheometer and bending beam tests. If a penetration grade is specified, use penetration test. If a viscosity grade is specified, use a viscosity test. The blend of new asphalt cement and the RAP asphalt binder shall meet [the dynamic shear rheometer at high temperature and bending beam at low temperature] [penetration] [viscosity] requirements in paragraph ASPHALT CEMENT BINDER. The virgin asphalt cement shall not be more than two standard asphalt material grades different than that specified in paragraph ASPHALT CEMENT BINDER. PART 3 EXECUTION NOTE: For Performance Graded (PG) asphalt cements, insert the plant temperature range from the Table below into the last sentence of the following paragraph. Performance Graded Asphalt Plant Mixing Temperatures Binder Grade   Mixing Temp Range (deg F)   Mixing Temp Range (deg C)   PG 46-28            240 - 295                  115 - 146   PG 46-34            240 - 295                  115 - 146   PG 46-40            240 - 295                  115 - 146   PG 52-28            240 - 300                  115 - 149   PG 52-34            240 - 300                  115 - 149   PG 52-40            240 - 300                  115 - 149   PG 52-46            240 - 300                  115 - 149   PG 58-22            260 - 310                  127 - 154   PG 58-28            260 - 310                  127 - 154   PG 58-34            260 - 310                  127 - 154   PG 64-22            265 - 320                  129 - 160   PG 64-28            265 - 320                  129 - 160   PG 64-34            265 - 320                  129 - 160   PG 67-22            275 - 325                  135 - 163   PG 70-22            280 - 330                  138 - 166   PG 70-28            275 - 325                  135 - 163   PG 76-22            285 - 335                  141 - 168   PG 76-28            280 - 330                  138 - 166   PG 82-22            290 - 340                  143 - 171 3.1 PREPARATION OF ASPHALT BINDER MATERIAL The asphalt cement material shall be heated avoiding local overheating and providing a continuous supply of the asphalt material to the mixer at a uniform temperature. The temperature of unmodified asphalts shall be no more than 160 degrees C 325 degrees F when added to the aggregates. Performance-Graded (PG) asphalts shall be within the temperature range of [_____] degreesC F when added to the aggregate. 3.2 PREPARATION OF MINERAL AGGREGATE The aggregate for the mixture shall be heated and dried prior to mixing. No damage shall occur to the aggregates due to the maximum temperature and rate of heating used. The temperature of the aggregate and mineral filler shall not exceed 175 degrees C 350 degrees F when the asphalt cement is added. The temperature shall not be lower than is required to obtain complete coating and uniform distribution on the aggregate particles and to provide a mixture of satisfactory workability. 3.3 PREPARATION OF HOT-MIX ASPHALT MIXTURE The aggregates and the asphalt cement shall be weighed or metered and introduced into the mixer in the amount specified by the JMF. The combined materials shall be mixed until the aggregate obtains a uniform coating of asphalt binder and is thoroughly distributed throughout the mixture. Wet mixing time shall be the shortest time that will produce a satisfactory mixture, but no less than 25 seconds for batch plants. The wet mixing time for all plants shall be established by the Contractor, based on the procedure for determining the percentage of coated particles described in ASTM D 2489/D 2489M, for each individual plant and for each type of aggregate used. The wet mixing time will be set to at least achieve 95 percent of coated particles. The moisture content of all hot-mix asphalt upon discharge from the plant shall not exceed 0.5 percent by total weight of mixture as measured by ASTM D 1461. 3.4 PREPARATION OF THE UNDERLYING SURFACE NOTE: If the underlying surface to be paved is an unbound granular layer, a prime coat should be applied, especially if this layer will be exposed to weather for an extended period of time prior to covering with an asphalt mixture. The prime coat may be deleted if the base course is covered with hot mix within 7 days and no significant rainfall is anticipated. If the base course is to receive traffic prior to application of the surface course, it should first be primed and cured. If the underlying surface to be paved is an existing asphalt or concrete layer, a tack coat should always be used to ensure an adequate bond between layers. Delete requirement for prime coat if a drainage layer is used beneath the hot mix layer. Immediately before placing the hot mix asphalt, the underlying course shall be cleaned of dust and debris. A [prime coat] [and/or] [tack coat] shall be applied in accordance with the contract specifications. 3.5 TEST SECTION NOTE: Delete requirement for a test section if the project requires less than 2000 tons. Prior to full production, the Contractor shall place a test section for each JMF used. The Contractor shall construct a test section 75 - 150 m 250 - 500 feet long and two paver passes wide placed for two lanes, with a longitudinal cold joint. The test section shall be of the same thickness as the course which it represents. The underlying grade or pavement structure upon which the test section is to be constructed shall be the same as the remainder of the course represented by the test section. The equipment and personnel used in construction of the test section shall be the same equipment to be used on the remainder of the course represented by the test section. The test section shall be placed as part of the project pavement as approved by the Contracting Officer. 3.5.1 Sampling and Testing for Test Section NOTE: Table 7 applies only to the test section. The limits in Tables 6, 7, and 8, apply to the results of 4 full scale production tests run for each lot. This is why the limits listed in Table 7 are different from those listed in Tables 6, 7, and 8. Select the appropriate VMA requirement to match the selected gradation. Select the appropriate stability and flow value to match the laboratory compactive effort (50 or 75 blows). One random sample shall be taken at the plant, triplicate specimens compacted, and tested for stability, flow, and laboratory air voids. A portion of the same sample shall be tested for theoretical maximum density (TMD), aggregate gradation and asphalt content. Four randomly selected cores shall be taken from the finished pavement mat, and four from the longitudinal joint, and tested for density. Random sampling shall be in accordance with procedures contained in ASTM D 3665. The test results shall be within the tolerances shown in Table 7 for work to continue. If all test results meet the specified requirements, the test section shall remain as part of the project pavement. If test results exceed the tolerances shown, the test section shall be removed and replaced at no cost to the Government and another test section shall be constructed. The test section shall be paid for with the first lot of paving Table 7.  Test Section Requirements for Material and Mixture Properties           Property                             Specification Limit   Aggregate Gradation-Percent Passing (Individual Test Result)      4.75 mm and larger                        JMF plus or minus 8      2.36, 1.18, 0.60, and 0.30 mm             JMF plus or minus 6      0.15 and 0.075 mm                         JMF plus or minus 2.0   Asphalt Content, Percent                     JMF plus or minus 0.5   (Individual Test Result)   Laboratory Air Voids, Percent   (Average of 3 specimens)                     JMF plus or minus 1.0   VMA, Percent (Average of 3 specimens)        [13] [14] [15] minimum   Stability, newtons (Average of 3 specimens)  [4450] [8000] minimum   Flow, 0.25 mm (Average of 3 specimens)       [8 - 16] [8 - 18]   Mat Density, Percent of TMD   (Average of 4 Random Cores)                  92.0 - 96.0   Joint Density, Percent of TMD   (Average of 4 Random Cores)                  90.5 - 92.5 Table 7.  Test Section Requirements for Material and Mixture Properties           Property                             Specification Limit   Aggregate Gradation-Percent Passing (Individual Test Result)      No. 4 and larger                          JMF plus or minus 8      No. 8, No. 16, No. 30, and No. 50         JMF plus or minus 6      No. 100 and No. 200                       JMF plus or minus 2.0   Asphalt Content, Percent                     JMF plus or minus 0.5   (Individual Test Result)   Laboratory Air Voids, Percent   (Average of 3 specimens)                     JMF plus or minus 1.0   VMA, Percent (Average of 3 specimens)        [13] [14] [15] minimum   Stability, pounds (Average of 3 specimens)   [1000] [1800] minimum   Flow, 0.01 inches (Average of 3 specimens)   [8 - 16] [8 - 18]   Mat Density, Percent of TMD   (Average of 4 Random Cores)                  92.0 - 96.0   Joint Density, Percent of TMD   (Average of 4 Random Cores)                  90.5 - 92.5 3.5.2 Additional Test Sections If the initial test section should prove to be unacceptable, the necessary adjustments to the JMF, plant operation, placing procedures, and/or rolling procedures shall be made. A second test section shall then be placed. Additional test sections, as required, shall be constructed and evaluated for conformance to the specifications. Full production shall not begin until an acceptable section has been constructed and accepted. 3.6 _{TESTING LABORATORY} The laboratory used to develop the JMF shall meet the requirements of ASTM D 3666. The Government will inspect the laboratory equipment and test procedures prior to the start of hot mix operations for conformance to ASTM D 3666 . The laboratory shall maintain the Corps certification for the duration of the project. A statement signed by the manager of the laboratory stating that it meets these requirements or clearly listing all deficiencies shall be submitted to the Contracting Officer prior to the start of construction. The statement shall contain as a minimum: a. Qualifications of personnel; laboratory manager, supervising technician, and testing technicians. b. A listing of equipment to be used in developing the job mix. c. A copy of the laboratory's quality control system. d. Evidence of participation in the AASHTO Materials Reference Laboratory (AMRL) program. 3.7 TRANSPORTING AND PLACING 3.7.1 Transporting NOTE: A material transfer vehicle has been shown to provide a pavement with improved smoothness and less segregation. A material transfer vehicle is recommended when doing major road construction. The designer should look at design index, speed of vehicle utilizing road and other factors in determining the requirement for a material load transfer vehicle. Remove last sentence if material transfer vehicle is not used. The hot-mix asphalt shall be transported from the mixing plant to the site in clean, tight vehicles. Deliveries shall be scheduled so that placing and compacting of mixture is uniform with minimum stopping and starting of the paver. Adequate artificial lighting shall be provided for night placements. Hauling over freshly placed material will not be permitted until the material has been compacted as specified, and allowed to cool to 60 degrees C 140 degrees F. To deliver mix to the paver, the Contractor shall use a material transfer vehicle which shall be operated to produce continuous forward motion of the paver. 3.7.2 Placing The mix shall be placed and compacted at a temperature suitable for obtaining density, surface smoothness, and other specified requirements. Upon arrival, the mixture shall be placed to the full width by an asphalt paver; it shall be struck off in a uniform layer of such depth that, when the work is completed, it shall have the required thickness and conform to the grade and contour indicated. The speed of the paver shall be regulated to eliminate pulling and tearing of the asphalt mat. Unless otherwise permitted, placement of the mixture shall begin along the centerline of a crowned section or on the high side of areas with a one-way slope. The mixture shall be placed in consecutive adjacent strips having a minimum width of 3 m 10 feet. The longitudinal joint in one course shall offset the longitudinal joint in the course immediately below by at least 300 mm 1 foot; however, the joint in the surface course shall be at the centerline of the pavement. Transverse joints in one course shall be offset by at least 3 m 10 feet from transverse joints in the previous course. Transverse joints in adjacent lanes shall be offset a minimum of 3 m 10 feet. On isolated areas where irregularities or unavoidable obstacles make the use of mechanical spreading and finishing equipment impractical, the mixture may be spread and luted by hand tools. 3.8 COMPACTION OF MIXTURE After placing, the mixture shall be thoroughly and uniformly compacted by rolling. The surface shall be compacted as soon as possible without causing displacement, cracking or shoving. The sequence of rolling operations and the type of rollers used shall be at the discretion of the Contractor. The speed of the roller shall, at all times, be sufficiently slow to avoid displacement of the hot mixture and be effective in compaction. Any displacement occurring as a result of reversing the direction of the roller, or from any other cause, shall be corrected at once. Sufficient rollers shall be furnished to handle the output of the plant. Rolling shall continue until the surface is of uniform texture, true to grade and cross section, and the required field density is obtained. To prevent adhesion of the mixture to the roller, the wheels shall be kept properly moistened but excessive water will not be permitted. In areas not accessible to the roller, the mixture shall be thoroughly compacted with hand tampers. Any mixture that becomes loose and broken, mixed with dirt, contains check-cracking, or is in any way defective shall be removed full depth, replaced with fresh hot mixture and immediately compacted to conform to the surrounding area. This work shall be done at the Contractor's expense. Skin patching will not be allowed. 3.9 JOINTS The formation of joints shall be made ensuring a continuous bond between the courses and to obtain the required density. All joints shall have the same texture as other sections of the course and meet the requirements for smoothness and grade. 3.9.1 Transverse Joints The roller shall not pass over the unprotected end of the freshly laid mixture, except when necessary to form a transverse joint. When necessary to form a transverse joint, it shall be made by means of placing a bulkhead or by tapering the course. The tapered edge shall be cut back to its full depth and width on a straight line to expose a vertical face prior to placing material at the joint . The cutback material shall be removed from the project. In both methods, all contact surfaces shall be given a light tack coat of asphalt material before placing any fresh mixture against the joint. 3.9.2 Longitudinal Joints Longitudinal joints which are irregular, damaged, uncompacted, cold (less than 80 degrees C 175 degrees F at the time of placing adjacent lanes), or otherwise defective, shall be cut back a maximum of 75 mm 3 inches from the top of the course with a cutting wheel to expose a clean, sound vertical surface for the full depth of the course. All cutback material shall be removed from the project. All contact surfaces shall be given a light tack coat of asphalt material prior to placing any fresh mixture against the joint. The Contractor will be allowed to use an alternate method if it can be demonstrated that density, smoothness, and texture can be met. 3.10 _{CONTRACTOR QUALITY CONTROL} NOTE: The Contractor may be able to meet the specified quality control requirements with in-house capability or may have to hire a material testing firm to provide the required quality control testing. 3.10.1 General Quality Control Requirements The Contractor shall develop an approved Quality Control Plan. Hot-mix asphalt for payment shall not be produced until the quality control plan has been approved. The plan shall address all elements which affect the quality of the pavement including, but not limited to: a. Mix Design b. Aggregate Grading c. Quality of Materials d. Stockpile Management e. Proportioning f. Mixing and Transportation g. Mixture Volumetrics h. Moisture Content of Mixtures i. Placing and Finishing j. Joints k. Compaction l. Surface Smoothness 3.10.2 Testing Laboratory NOTE: For projects less than 1000 tons delete the requirements for a job site laboratory. For small projects the Contractor may use a commercially approved laboratory. The Contractor shall provide a fully equipped asphalt laboratory located at the plant or job site. The laboratory shall meet the requirements as required in ASTM D 3666. Laboratory facilities shall be kept clean and all equipment maintained in proper working condition. The Contracting Officer shall be permitted unrestricted access to inspect the Contractor's laboratory facility, to witness quality control activities, and to perform any check testing desired. The Contracting Officer will advise the Contractor in writing of any noted deficiencies concerning the laboratory facility, equipment, supplies, or testing personnel and procedures. When the deficiencies are serious enough to adversely affect test results, the incorporation of the materials into the work shall be suspended immediately and will not be permitted to resume until the deficiencies are corrected. 3.10.3 Quality Control Testing The Contractor shall perform all quality control tests applicable to these specifications and as set forth in the Quality Control Program. The testing program shall include, but shall not be limited to, tests for the control of asphalt content, aggregate gradation, temperatures, aggregate moisture, moisture in the asphalt mixture, laboratory air voids, stability, flow, in-place density, grade and smoothness. A Quality Control Testing Plan shall be developed as part of the Quality Control Program. 3.10.3.1 Asphalt Content A minimum of two tests to determine asphalt content will be performed per lot (a lot is defined in paragraph MATERIAL ACCEPTANCE and PERCENT PAYMENT) by one of the following methods: the extraction method in accordance with ASTM D 2172, Method A or B, the ignition method in accordance with ASTM D 6307, or the nuclear method in accordance with ASTM D 4125. Calibrate the ignition oven or the nuclear gauge for the specific mix being used. For the extraction method, the weight of ash, as described in ASTM D 2172, shall be determined as part of the first extraction test performed at the beginning of plant production; and as part of every tenth extraction test performed thereafter, for the duration of plant production. The last weight of ash value obtained shall be used in the calculation of the asphalt content for the mixture. 3.10.3.2 Gradation Aggregate gradations shall be determined a minimum of twice per lot from mechanical analysis of recovered aggregate in accordance with ASTM D 5444. When asphalt content is determined by the ignition oven or nuclear method, aggregate gradation shall be determined from hot bin samples on batch plants, or from the cold feed on drum mix plants. For batch plants, aggregates shall be tested in accordance with ASTM C 136 using actual batch weights to determine the combined aggregate gradation of the mixture. 3.10.3.3 Temperatures Temperatures shall be checked at least four times per lot, at necessary locations, to determine the temperature at the dryer, the asphalt cement in the storage tank, the asphalt mixture at the plant, and the asphalt mixture at the job site. 3.10.3.4 Aggregate Moisture The moisture content of aggregate used for production shall be determined a minimum of once per lot in accordance with ASTM C 566. 3.10.3.5 Moisture Content of Mixture The moisture content of the mixture shall be determined at least once per lot in accordance with ASTM D 1461 or an approved alternate procedure. 3.10.3.6 Laboratory Air Voids, Marshall Stability and Flow Mixture samples shall be taken at least four times per lot and compacted into specimens, using [50] [75] blows per side with the hand-held Marshall hammer as described in ASTM D 6926. Hot-mix provided under the DOT Superpave option shall be compacted in accordance with the DOT requirements. After compaction, the laboratory air voids of each specimen shall be determined. Stability and flow shall be determined for the Marshall-compacted specimens, in accordance with ASTM D 6927. 3.10.3.7 In-Place Density The Contractor shall conduct any necessary testing to ensure the specified density is achieved. A nuclear gauge may be used to monitor pavement density in accordance with ASTM D 2950. 3.10.3.8 Grade and Smoothness NOTE: Retain requirements for grade for projects having large paved areas where standing water or ponding of water may occur and projects with plan and profile details. All other projects shall be evaluated for the possibility of standing water before removing the grade requirements. The Contractor shall conduct the necessary checks to ensure the grade and smoothness requirements are met in accordance with paragraphs MATERIAL ACCEPTANCE and PERCENT PAYMENT. 3.10.3.9 Additional Testing Any additional testing, which the Contractor deems necessary to control the process, may be performed at the Contractor's option. 3.10.3.10 _{QC Monitoring} The Contractor shall submit all QC test results to the Contracting Officer on a daily basis as the tests are performed. The Contracting Officer reserves the right to monitor any of the Contractor's quality control testing and to perform duplicate testing as a check to the Contractor's quality control testing. 3.10.4 Sampling When directed by the Contracting Officer, the Contractor shall sample and test any material which appears inconsistent with similar material being produced, unless such material is voluntarily removed and replaced or deficiencies corrected by the Contractor. All sampling shall be in accordance with standard procedures specified. 3.10.5 Control Charts NOTE: For projects less than 2000 tons the control chart requirements may be deleted For process control, the Contractor shall establish and maintain linear control charts on both individual samples and the running average of last four samples for the parameters listed in Table 8, as a minimum. These control charts shall be posted as directed by the Contracting Officer and shall be kept current at all times. The control charts shall identify the project number, the test parameter being plotted, the individual sample numbers, the Action and Suspension Limits listed in Table 8 applicable to the test parameter being plotted, and the Contractor's test results. Target values from the JMF shall also be shown on the control charts as indicators of central tendency for the cumulative percent passing, asphalt content, and laboratory air voids parameters. When the test results exceed either applicable Action Limit, the Contractor shall take immediate steps to bring the process back in control. When the test results exceed either applicable Suspension Limit, the Contractor shall halt production until the problem is solved. The Contractor shall use the control charts as part of the process control system for identifying trends so that potential problems can be corrected before they occur. Decisions concerning mix modifications shall be made based on analysis of the results provided in the control charts. The Quality Control Plan shall indicate the appropriate action which shall be taken to bring the process into control when certain parameters exceed their Action Limits. (Table 8.  Action and Suspension Limits for the Parameters to be Plotted on Individual and Running Average Control  Charts                                  Running Average of                                  Individual Samples   Last Four Samples                                 Action    Suspension  Action  Suspension   Parameter to be Plotted        Limit    Limit       Limit   Limit       ----------------------------------------------------------------------   4.75 mm sieve, Cumulative %      6         8         4        5   Passing, deviation from JMF   target; plus or minus values   0.6 mm sieve, Cumulative %       4         6         3        4   Passing, deviation from JMF   target; plus or minus values   0.075 mm sieve, Cumulative %     1.4       2.0       1.1      1.5   Passing, deviation from JMF   target; plus or minus values   Stability, newtons (minimum)         75 Blow JMF                     8000      7560      8440     8000    50 Blow JMF                     4450      4000      4900     4450   Flow, 0.25 mm    75 Blow JMF                     8 min.    7 min.    9 min.   8 min.                                    16 max.   17 max.   15 max.  16 max.    50 Blow JMF                     8 min.    7 min.    9 min.   8 min.                                    18 max.   19 max.   17 max.  18 max   Asphalt content, % deviation     0.4       0.5       0.2      0.3   from JMF target; plus or   minus value   Laboratory Air Voids, %          No specific action and suspension   deviation from JMF target        limits set since this parameter is   value                            used to determine percent payment   In-place Mat Density,            No specific action and suspension   % of TMD                         limits set since this parameter is                                    used to determine percent payment   In-place Joint Density,          No specific action and suspension   % of TMD                         limits set since this parameter is                                    used to determine percent payment) Table 8.  Action and Suspension Limits for the Parameters to be Plotted on Individual and Running Average Control  Charts                                                                   Running Average of                                  Individual Samples    Last Four Samples                                     Action   Suspension  Action  Suspension   Parameter to be Plotted        Limit      Limit     Limit    Limit         ----------------------------------------------------------------------   No. 4 sieve, Cumulative %        6         8         4        5   Passing, deviation from JMF   target; plus or minus values   No. 30 sieve, Cumulative %       4         6         3        4   Passing, deviation from JMF   target; plus or minus values   No. 200 sieve, Cumulative %      1.4       2.0       1.1      1.5   Passing, deviation from JMF   target; plus or minus values   Stability, pounds  (minimum)        75 Blow JMF                     1800      1700      1900     1800    50 Blow JMF                     1000      900       1100     1000   Flow, 0.01 inches                    75 Blow                         8 min.    7 min.    9 min.   8 min.                                    16 max.   17 max.   15 max.  16 max.    50 Blow                         8 min.    7 min.    9 min.   8 min.                                    18 max.   19 max.   17 max.  18 max.   Asphalt content, % deviation     0.4       0.5       0.2      0.3   from JMF target; plus or minus   value   Laboratory Air Voids, %          No specific action and suspension   deviation from JMF target        limits set since this parameter is   value                            used to determine percent payment   In-place Mat Density,            No specific action and suspension   % of TMD                         limits set since this parameter is                                    used to determine percent payment   In-place Joint Density,          No specific action and suspension   % of TMD                         limits set since this parameter is                                    used to determine percent payment 3.11 _{MATERIAL ACCEPTANCE} NOTE: As written, this specification requires the Contractor to hire an independent material testing laboratory to perform the testing listed in this Section. The results are required to be forwarded daily to the Contracting Officer as the basis for acceptance. The project engineer may choose to have additional tests conducted by the QA test agency to monitor aggregate gradation, asphalt content, Marshall stability and flow. These tests would serve as a check to the Contractor's QC testing. Marshall stability and flow could be done at minimal cost since the specimens have to be made anyway for laboratory air void determination. For lot size determination, use a lot size that will represent an amount of asphalt placed in one day or any half day's pavement production, depending on the extent of the project. The lot size should not be small enough to overburden the testing laboratory but large enough to get a representative sample of the work being performed. Testing for acceptability of work will be performed by an independent laboratory hired by the Contractor. Test results and payment calculations shall be forwarded daily to the Contracting Officer. Acceptance of the plant produced mix and in-place requirements will be on a lot to lot basis. A standard lot for all requirements will be equal to [_____] [2000 metric 2000 short tons] [8 hours of production]. Where appropriate, adjustment in payment for individual lots of hot-mix asphalt will be made based on in-place density, laboratory air voids, grade and smoothness in accordance with the following paragraphs. Grade and surface smoothness determinations will be made on the lot as a whole. Exceptions or adjustments to this will be made in situations where the mix within one lot is placed as part of both the intermediate and surface courses, thus grade and smoothness measurements for the entire lot cannot be made. In order to evaluate laboratory air voids and in-place (field) density, each lot will be divided into four equal sublots. 3.11.1 Sublot Sampling One random mixture sample for determining laboratory air voids, theoretical maximum density, and for any additional testing the Contracting Officer desires, will be taken from a loaded truck delivering mixture to each sublot, or other appropriate location for each sublot. All samples will be selected randomly, using commonly recognized methods of assuring randomness conforming to ASTM D 3665 and employing tables of random numbers or computer programs. Laboratory air voids will be determined from three laboratory compacted specimens of each sublot sample in accordance with ASTM D 6926. The specimens will be compacted within 2 hours of the time the mixture was loaded into trucks at the asphalt plant. Samples will not be reheated prior to compaction and insulated containers will be used as necessary to maintain the temperature. 3.11.2 Additional Sampling and Testing The Contracting Officer reserves the right to direct additional samples and tests for any area which appears to deviate from the specification requirements. The cost of any additional testing will be paid for by the Government. Testing in these areas will be in addition to the lot testing, and the requirements for these areas will be the same as those for a lot. 3.11.3 Grade NOTE: The grade and surface smoothness requirements specified below are for the final wearing surface only. If there is a requirement to test and control the grade and smoothness for the intermediate courses, i.e., when the intermediate courses will be exposed to traffic, slight modifications to this specification will be required. The final wearing surface of pavement shall conform to the elevations and cross sections shown and shall vary not more than 15 mm 0.05 foot from the plan grade established and approved at site of work. Finished surfaces at juncture with other pavements shall coincide with finished surfaces of abutting pavements. Deviation from the plan elevation will not be permitted in areas of pavements where closer conformance with planned elevation is required for the proper functioning of drainage and other appurtenant structures involved. The grade will be determined by running lines of levels at intervals of 7.6 m 25 feet, or less, longitudinally and transversely, to determine the elevation of the completed pavement surface. Within 5 working days, after the completion of a particular lot incorporating the final wearing surface, the Contractor shall test the final wearing surface of the pavement for conformance with the specified plan grade. Diamond grinding may be used to remove high spots to meet grade requirements. Skin patching for correcting low areas or planing or milling for correcting high areas will not be permitted. 3.11.4 Surface Smoothness NOTE: Edit these paragraphs as appropriate to the project. Specify the profilograph method for testing in the longitudinal direction for road length exceeding 1/4 mile (0.4 km). Specify the straightedge method for longitudinal testing on road lengths less than 1/4 mile (0.4 km) and for all transverse smoothness testing. Use straightedge testing in both longitudinal and transverse directions for parking lots and all other roads and for roads with design speeds less than 30 mph. The Contractor shall use one of the following methods to test and evaluate surface smoothness of the pavement. All testing shall be performed in the presence of the Contracting Officer. Detailed notes of the results of the testing shall be kept and a copy furnished to the Government immediately after each day's testing. [The profilograph method shall be used for all longitudinal testing, except where the runs would be less than 60 m 200 feet in length and the ends where the straightedge shall be used.] Where drawings show required deviations from a plane surface (crowns, drainage inlets, etc.), the surface shall be finished to meet the approval of the Contracting Officer. 3.11.4.1 Smoothness Requirements a. Straightedge Testing: The finished surfaces of the pavements shall have no abrupt change of 6 mm 1/4 inch or more, and all pavements shall be within the tolerances of 6 mm 1/4 inch in both the longitudinal and transverse directions, when tested with an approved 4 m 12 feet straightedge. b. Profilograph Testing: The finished surfaces of the pavements shall have no abrupt change of 3 mm 1/8 inch or more, and each 0.1 km 0.1 mile segment of each pavement lot shall have a Profile Index not greater than 140 mm/km 9 inches/mile when tested with an approved California-type profilograph. If the extent of the pavement in either direction is less than 60 m 200 feet, that direction shall be tested by the straightedge method and shall meet requirements specified above. 3.11.4.2 Testing Method After the final rolling, but not later than 24 hours after placement, the surface of the pavement in each entire lot shall be tested by the Contractor in such a manner as to reveal all surface irregularities exceeding the tolerances specified above. Separate testing of individual sublots is not required. If any pavement areas are ground, these areas shall be retested immediately after grinding. Each lot of the pavement shall be tested in both a longitudinal and a transverse direction on parallel lines. The transverse lines shall be 4.5 m 15 feet or less apart, as directed. The longitudinal lines shall be at the centerline of each paving lane for lanes less than 6.1 m 20 feet wide and at the third points for lanes 6.1 m 20 feet or wider. Other areas having obvious deviations shall also be tested. Longitudinal testing lines shall be continuous across all joints. a. Straightedge Testing. The straightedge shall be held in contact with the surface and moved ahead one-half the length of the straightedge for each successive measurement. The amount of surface irregularity shall be determined by placing the freestanding (unleveled) straightedge on the pavement surface and allowing it to rest upon the two highest spots covered by its length, and measuring the maximum gap between the straightedge and the pavement surface in the area between these two high points. b. Profilograph Testing. Profilograph testing shall be performed using approved equipment and procedures described in CDT Test 526. The equipment shall utilize electronic recording and automatic computerized reduction of data to indicate "must-grind" bumps and the Profile Index for each 0.1 km 0.1 mile segment of each pavement lot. Grade breaks on parking lots shall be accomodated by breaking the profile segment into shorter sections and repositioning the blanking band on each segment. The "blanking band" shall be 5 mm 0.2 inches wide and the "bump template" shall span 25 mm 1 inch with an offset of 7.5 mm 0.3 inch. The Profile Index shall be computed for each pass of the profilograph in each 0.1 km 0.1 mile segment. The Profile Index for each segment shall be the average of the Profile Indices for each pass in each segment. The profilograph shall be operated by a DOT approved operator. A copy of the reduced tapes shall be furnished the Government at the end of each day's testing.