UFGS_32-12-16_HMA.doc

USACE / NAVFAC / AFCESA / NASA UFGS-32 12 16 (August 2009)

UFGS-32 12 16 (August 2008)

UNIFIED FACILITIES GUIDE SPECIFICATIONS

Edited For Contract # FA8201-11-D-0004 Task-0006 Project Engineering Technician: Kevin Patzer

SECTION TABLE OF CONTENTS

DIVISION 32 - EXTERIOR IMPROVEMENTS

SECTION 32 12 16

HOT-MIX ASPHALT (HMA) FOR ROADS

08/09

PART 1 GENERAL

1.1 UNIT PRICES

1.1.1 Method of Measurement

1.1.2 Basis of Payment

1.1.3 Percent Payment

1.1.4 Laboratory Air Voids and Theoretical Maximum Density

1.1.5 Mean Absolute Deviation

1.1.6 In-place Density

1.1.7 Mat and Joint Densities

1.1.8 Pay Factor Based on In-place Density

1.1.9 Pay Factor for Grade

1.1.10 Payment Adjustment for Smoothness

1.2 REFERENCES

1.3 SYSTEM DESCRIPTION

1.3.1 Asphalt Mixing Plant

1.3.2 Hauling Equipment

1.3.3 Asphalt Pavers

1.3.3.1 Receiving Hopper

1.3.3.2 Automatic Grade Controls

1.3.4 Rollers

1.4 SUBMITTALS

1.5 ENVIRONMENTAL REQUIREMENTS

PART 2 PRODUCTS

2.1 AGGREGATES

2.1.1 Coarse Aggregate

2.1.2 Fine Aggregate

2.1.3 Mineral Filler

2.1.4 Aggregate Gradation

2.2 ASPHALT CEMENT BINDER

2.3 MIX DESIGN

2.3.1 JMF Requirements

2.3.2 Adjustments to Field JMF

2.4 RECYCLED HOT MIX ASPHALT

2.4.1 RAP Aggregates and Asphalt Cement

2.4.2 RAP Mix

PART 3 EXECUTION

3.1 PREPARATION OF ASPHALT BINDER MATERIAL

3.2 PREPARATION OF MINERAL AGGREGATE

3.3 PREPARATION OF HOT-MIX ASPHALT MIXTURE

3.4 PREPARATION OF THE UNDERLYING SURFACE

3.5 TEST SECTION

3.5.1 Sampling and Testing for Test Section

3.5.2 Additional Test Sections

3.6 TESTING LABORATORY

3.7 TRANSPORTING AND PLACING

3.7.1 Transporting

3.7.2 Placing

3.8 COMPACTION OF MIXTURE

3.9 JOINTS

3.9.1 Transverse Joints

3.9.2 Longitudinal Joints

3.10 CONTRACTOR QUALITY CONTROL

3.10.1 General Quality Control Requirements

3.10.2 Testing Laboratory

3.10.3 Quality Control Testing

3.10.3.1 Asphalt Content

3.10.3.2 Gradation

3.10.3.3 Temperatures

3.10.3.4 Aggregate Moisture

3.10.3.5 Moisture Content of Mixture

3.10.3.6 Laboratory Air Voids, Marshall Stability and Flow

3.10.3.7 In-Place Density

3.10.3.8 Grade and Smoothness

3.10.3.9 Additional Testing

3.10.3.10 QC Monitoring

3.10.4 Sampling

3.10.5 Control Charts

3.11 MATERIAL ACCEPTANCE

3.11.1 Sub-lot Sampling

3.11.2 Additional Sampling and Testing

3.11.3 Grade

3.11.4 Surface Smoothness

3.11.4.1 Smoothness Requirements

3.11.4.2 Testing Method

-- End of Section Table of Contents --

USACE / NAVFAC / AFCESA / NASA UFGS-32 12 16 (August 2009) Preparing Activity: USACE Superseding UFGS-32 12 16 (August 2008)

UNIFIED FACILITIES GUIDE SPECIFICATIONS

References are in agreement with UMRL dated January 2011

SECTION 32 12 16

HOT-MIX ASPHALT (HMA) FOR ROADS

08/09

PART 1 GENERAL

1.1 UNIT PRICES

1.1.1 Method of Measurement

[The measured quantity of hot-mix asphalt will be paid for and included in the lump-sum contract price. Payment will 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.]

1.1.3 Percent Payment

NOT APPLICABLE TO THIS PROJECT

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 lot sample using ASTM D 2041. The laboratory air voids and Theoretical Maximum Density for each lot will be determined as the average of the two random samples per lot. Laboratory air void calculations for each lot will use the latest theoretical maximum density values obtained, either for that lot or the previous lot. The mean absolute deviation of the laboratory air void contents from the JMF air void content will be evaluated and a pass or fail determination will be made based on the established JMF target tolerances. All laboratory air void tests will be completed and reported within 24 hours after completion of construction of each sub-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 sub-lot sample are determined to be 3.5, 3.0, 4.0, and 3.7. Assume that the target air voids from the JMF are 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.

1.1.6 In-place Density

For determining in-place density, 4 random cores (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 sub-lot. Each random core will be full thickness of the layer being placed. After air drying to a constant weight, cores obtained from the mat will be used for in-place density determination. Core locations will be determined by the Project Manager.

1.1.7 Mat and Joint Densities

The average in-place mat and joint densities are expressed as a percentage of the average Theoretical Maximum Density (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 for a lot are determined and compared to the tolerances and a pass or fail determination will be made by the Project Manager.

1.1.8 Pay Factor Based on In-place Density

NOT APPLICABLE TO THIS PROJECT

1.1.9 Pay Factor for Grade

NOT APPLICABLE TO THIS PROJECT

1.1.10 Payment Adjustment for Smoothness

NOT APPLICABLE TO THIS PROJECT

1.2 REFERENCES

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 (2010) Standard Specification for Performance-Graded Asphalt Binder

ASPHALT INSTITUTE (AI)

AI MS-02 (1997 6th Ed) Mix Design Methods AI MS-22 (2001; 2nd Ed) Construction of Hot-Mix Asphalt Pavements AI SP-2 (2001; 3rd Ed) Superpave Mix Design

ASTM INTERNATIONAL (ASTM)

ASTM C 117 (2004) Standard Test Method for Materials Finer than 75-um (No. 200) Sieve in Mineral Aggregates by Washing ASTM C 1252 (2010) Standard Test Methods for Un-compacted Void Content of Fine Aggregate (as Influenced by Particle Shape, Surface Texture, and Grading) ASTM C 127 (2007) Standard Test Method for Density, Relative Density (Specific Gravity), and Absorption of Coarse Aggregate ASTM C 128 (2007a) Standard Test Method for Density, Relative Density (Specific Gravity), and Absorption of Fine Aggregate ASTM C 131 (2006) Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine ASTM C 136 (2006) Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates ASTM C 142 (1997; R 2004) Standard Test Method for Clay Lumps and Friable Particles in Aggregates ASTM C 29/C 29M (2009) Standard Test Method for Bulk Density ("Unit Weight") and Voids in Aggregate ASTM C 566 (1997; R 2004) Standard Test Method for Total Evaporable Moisture Content of Aggregate by Drying ASTM C 88 (2005) Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or Magnesium Sulfate ASTM D 140/D 140M (2009) Standard Practice for Sampling SECTION 32 12 16 Page 10 Bituminous Materials ASTM D 1461 (1985; R 2006) Moisture or Volatile Distillates in Bituminous Paving Mixtures ASTM D 2041 (2003a) Theoretical Maximum Specific Gravity and Density of Bituminous Paving Mixtures ASTM D 2172 (2005) Quantitative Extraction of Bitumen from Bituminous Paving Mixtures ASTM D 2419 (2009) Sand Equivalent Value of Soils and Fine Aggregate ASTM D 242/D 242M (2009) Mineral Filler for Bituminous Paving Mixtures ASTM D 2489/D 2489M (2008) Estimating Degree of Particle Coating of Bituminous-Aggregate Mixtures ASTM D 2726 (2010) Bulk Specific Gravity and Density of Non-Absorptive Compacted Bituminous Mixtures ASTM D 2950 (2009) Density of Bituminous Concrete in Place by Nuclear Methods ASTM D 3665 (2007) Random Sampling of Construction Materials ASTM D 3666 (2009a) Minimum Requirements for Agencies Testing and Inspecting Road and Paving Materials ASTM D 4125 (2005) Asphalt Content of Bituminous Mixtures by the Nuclear Method ASTM D 4791 (2010) Flat Particles, Elongated Particles or Flat and Elongated Particles in Coarse Aggregate ASTM D 4867/D 4867M (2009) Effect of Moisture on Asphalt Concrete Paving Mixtures ASTM D 5444 (2008) Mechanical Size Analysis of Extracted Aggregate ASTM D 6307 (2005; R 2010) Asphalt Content of Hot Mix Asphalt by Ignition Method ASTM D 6925 (2009) Standard Test Method for Preparation and Determination of the Relative Density of Hot Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor ASTM D 6926 (2010) Standard Practice for Preparation of Bituminous Specimens Using Marshall SECTION 32 12 16 Page 11 Apparatus ASTM D 6927 (2006) Standard Test Method for Marshall Stability and Flow of Bituminous Mixtures ASTM D 995 (1995b; R 2002) Mixing Plants for Hot-Mixed, Hot-Laid Bituminous Paving Mixtures ASTM D3381/D3381M (2009a) Viscosity-Graded Asphalt Cement for Use in Pavement Construction ASTM D946/D946M (2009a) Penetration-Graded Asphalt Cement for Use in Pavement Construction

STATE OF CALIFORNIA DEPARTMENT OF TRANSPORTATION (CALTRANS)

CALTRANS Test 526 (2002) Operation of California Profilograph and Evaluation of Profiles

U.S. ARMY CORPS OF ENGINEERS (USACE)

COE CRD-C 171 (1995) Standard Test Method for Determining Percentage of Crushed Particles in Aggregate

1.3 SYSTEM DESCRIPTION

Perform the work consisting 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. Construct each course to the depth, section, or elevation required by the drawings and roll, finish, and approve it 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. Weigh the asphalt mixture on approved, certified scales at the Contractor's expense. Inspect and seal scales at least annually by an approved calibration laboratory.

b. Testing Facilities. 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. Provide the Project Manager with 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.

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

Provide trucks for hauling hot-mix asphalt having 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

Provide asphalt pavers which are self-propelled, with an activated screed, heated as necessary, and 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

Provide paver with a receiving hopper of sufficient capacity to permit a uniform spreading operation and 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

If an automatic grade control device is used, equip the paver 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. Provide controls 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 string line 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. Do not use equipment which causes excessive crushing of the aggregate.

1.4 SUBMITTALS

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, [___PM__]] Proposed JMF.

Contractor Quality Control[; G][; G, [_PM____]] Quality control plan.

Material Acceptance[; G][; G, [__PM___]] Acceptance test results. [; G][; G, [__PM___]]

SD-04 Samples

Asphalt Cement Binder A 20 L 5 gallon sample for mix design verification. [; G][; G, [__PM___]]

Aggregates Sufficient materials to produce 90 kg 200 lb of blended mixture for mix design verification. [; G][; G, [__PM___]]

SD-06 Test Reports

Aggregates[; G][; G, [__PM___]]

QC Monitoring QC test results. [; G][; G, [__PM___]]

SD-07 Certificates

Asphalt Cement Binder[; G][; G, [_PM____]] 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 [; G][; G, [__PM___]]

1.5 ENVIRONMENTAL REQUIREMENTS

Do not place the hot-mix asphalt 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

Provide aggregates consisting 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. Submit all aggregate test results and samples to the Contracting Officer at least 14 days prior to start of construction.

2.1.1 Coarse Aggregate

Provide coarse aggregate consisting 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, with 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

Fine aggregate shall consist of clean, sound, tough, durable particles free from coatings of clay, silt, or any objectionable material and containing 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 un-compacted void content not less than 45.0 percent when tested in accordance with ASTM C 1252 Method A.

c. The quantity of natural sand (non-crushed 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 non-plastic material meeting the requirements of ASTM D 242/D 242M.

2.1.4 Aggregate Gradation

The combined aggregate gradation shall conform to gradations specified in Table 4 Gradation 3 for this project, 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

Table 4. Aggregate Gradations

2.2 ASPHALT CEMENT BINDER

Asphalt cement binder shall conform to AASHTO M 320 Performance Grade (PG) [_58-28____]. Data indicating grade certification shall be provided by the supplier at the time of delivery of each load to the mix plant. Submit copies of these certifications to the Project Manager. The supplier is defined as the last source of any modification to the binder. The Project Manager may sample and test the binder at the mix plant at any time before or during mix production. Obtain samples for this verification testing in accordance with ASTM D 140/D 140M and in the presence of the Project Manager.

Furnish these samples to the Project Manager for the verification testing, which shall be at no cost to the Contractor? Submit samples of the asphalt cement specified for approval not less than 14 days before start of the test section.

2.3 MIX DESIGN

a. 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).

Do not produce hot-mix asphalt for payment until a JMF has been approved. The hot-mix asphalt shall be designed in accordance with Marshall (MS-02), procedures and the criteria shown in Table 5. Use the hand-held hammer to compact the specimens for Marshall mix design.

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. Provide an anti-strip agent, if required, 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.

2.3.1 JMF Requirements

Submit in writing the job mix formula for approval at least 14 days prior to the start of the test section including 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. (NA for Superpave)

f. Number of gyrations of Superpave gyratory compactor, (NA for Marshall mix design)

g. Laboratory mixing temperature.

h. Lab compaction temperature.

i. Temperature-viscosity relationship of the asphalt cement.

j. Plot of the combined gradation on the 0.45 power gradation chart, stating the nominal maximum size.

k. Graphical plots of stability (NA for Superpave), flow (NA for Superpave), air voids, voids in the mineral aggregate, and unit weight versus asphalt content as shown in AI MS-02.

l. Specific gravity and absorption of each aggregate.

m. Percent natural sand.

n. Percent particles with 2 or more fractured faces (in coarse aggregate).

o. Fine aggregate angularity.

p. Percent flat or elongated particles (in coarse aggregate).

q. Tensile Strength Ratio(TSR).

r. Anti-strip agent (if required) and amount.

s. List of all modifiers and amount.

t. Correlation of hand-held hammer with mechanical hammer (NA for Superpave).

u. 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. Mix Design Criteria

Test Property 50 Blows Mix 75 Blows 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)

TSR, minimum percent 75 75 SECTION 32 12 16 Page 21

Table 5. Mix Design Criteria

Test Property 50 Blows Mix 75 Blows 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)

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 C 127 and ASTM C 128 bulk specific gravity for the aggregate.

2.3.2 Adjustments to Field JMF

Keep the Laboratory JMF for each mixture in effect until a new formula is approved in writing by the Project Manager. Should a change in sources of any materials be made, perform a new laboratory JMF design 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 written approval of the Project Manager.

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

If adjustments are needed that exceed these limits, develop a new mix design. Tolerances given above may permit the aggregate grading to be outside the limits shown in Table 4; while not desirable, this is acceptable.

2.4 RECYCLED HOT MIX ASPHALT

Recycled HMA shall consist of reclaimed asphalt pavement (RAP), coarse aggregate, fine aggregate, mineral filler, and asphalt cement to produce 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.

Design the recycled HMA mix 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. Establish the percentage of asphalt in the RAP for the mixture design according to ASTM D 2172 or ASTM D 6307 using the appropriate dust correction procedure.

2.4.2 RAP Mix

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

Performance Graded Asphalt Plant Mixing Temperatures Binder Grade Mixing Temp Range (deg F) Mixing Temp Range (deg C)

3.1 PREPARATION OF ASPHALT BINDER MATERIAL

Heat the asphalt cement material 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 [__260 – 310 ___] degrees F when added to the aggregate.

3.2 PREPARATION OF MINERAL AGGREGATE

Heat and dry the aggregate for the mixture 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. Mix the combined materials 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. Establish the wet mixing time for all plants 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

Immediately before placing the hot mix asphalt, clean the underlying course of dust and debris. Apply [water in order to bring the base course to the optimum moisture/density range.]

3.5 TEST SECTION

Prior to full production, place a test section for each JMF used.

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. Place the test section as part of the project pavement, as approved by the Project Manager.

3.5.1 Sampling and Testing for Test Section

NOTE: Table 7 applies only to the test section.

Take one random sample at the plant, triplicate specimens compacted, and tested for stability, flow, and laboratory air voids. Test a portion of the same sample for theoretical maximum density (TMD), aggregate gradation and asphalt content. Take four randomly selected cores 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

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 minimum for 50 blows] [8000 minimum for 75 blows]

Flow, 0.25 mm (Average of 3 specimens) [8 - 18 for 50 blows] [8 - 16 for 75 blows]

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

Laboratory Air Voids, Percent (Average of 3 specimens) JMF plus or minus 1.0

VMA, Percent (Average of 3 specimens) [use value from gradation] [13] [14] [15] minimum

Stability, pounds (Average of 3 specimens) [1000 minimum for 50 blows] [1800 minimum for 75 blows]

Flow, 0.01 inches (Average of 3 specimens) [8 - 18 for 50 blows] [8 - 16 for 75 blows]

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, make the necessary adjustments to the JMF, plant operation, placing procedures, and/or rolling procedures and place a second test section. 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

Use a laboratory to develop the JMF that meets 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 Project Manager 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

MATERIAL TRANSFER VEHICLE NOT REQUIRED FOR THIS PROJECT.

Transport the hot-mix asphalt from the mixing plant to the site in clean, tight vehicles. The material shall not be dumped on the ground for any reason, unless a material transfer vehicle is in use or the project manager approves dumping on the ground in irregular areas which will not allow trucks to access the paver. Schedule deliveries so that placing and compacting of mixture are uniform with minimum stopping and starting of the paver.

Provide adequate artificial lighting 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, use a material transfer vehicle operated to produce continuous forward motion of the paver.

3.7.2 Placing

Place and compact the mix at a temperature suitable for obtaining density, surface smoothness, and other specified requirements. Upon arrival, place the mixture 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 will have the required thickness and conform to the grade and contour indicated. Regulate the speed of the paver 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. Place the mixture 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. Compact the surface 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, shall be sufficiently slow to avoid displacement of the hot mixture and shall 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. Furnish sufficient rollers to handle the output of the plant. Continue rolling 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, keep the wheels 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 performed 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

Do not pass the roller 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. Remove the cutback material from the project. In both methods, all contact surfaces shall be given a light tack coat of emulsified asphalt material before placing any fresh mixture against the joint.

3.9.2 Longitudinal Joints

Longitudinal joints which are irregular, damaged, un-compacted 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

3.10.1 General Quality Control Requirements

Develop an approved Quality Control Plan. Do not produce hot-mix asphalt for payment until the quality control plan has been approved addressing 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

Provide a fully equipped asphalt laboratory located at the plant or job site and meeting the pertinent requirements in ASTM D 3666. Laboratory facilities shall be kept clean and all equipment maintained in proper working condition. The Project Manager 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 Project Manager 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. With Project Manager’s written approval the contractor may use an accredited off site materials testing sub-contractor.

3.10.3 Quality Control Testing

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 (NA for Superpave), flow (NA for Superpave), in-place density, grade and smoothness. Develop a Quality Control Testing Plan 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, determine the weight of ash, as described in ASTM D 2172, 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

Determine aggregate gradations 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, test aggregates in accordance with ASTM C 136 using actual batch weights to determine the combined aggregate gradation of the mixture.

3.10.3.3 Temperatures

Check temperatures 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

Determine the moisture content of aggregate used for production a minimum of once per lot in accordance with ASTM C 566.

3.10.3.5 Moisture Content of Mixture

Determine the moisture content of the mixture 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

Take mixture samples at least two times per lot compacted into specimens, using [50] [75] blows per side with the hand-held Marshall hammer as described in ASTM D 6926. When the Superpave gyratory compactor is used, mixes will be compacted to [50] [75] gyrations in accordance with ASTM D 6925. Hot-mix provided under the DOT Superpave option shall be compacted in accordance with the DOT requirements. After compaction, determine the laboratory air voids of each specimen. Stability and flow shall be determined for the Marshall-compacted specimens, in accordance with ASTM D 6927.

3.10.3.7 In-Place Density

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

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

Submit all QC test results to the Contracting Officer on a daily basis as the tests are performed. The project manager 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 project manager, sample and test any material appearing 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

For process control, 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 Project Manager and 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, take immediate steps to bring the process back in control. When the test results exceed either applicable Suspension Limit, halt production until the problem is solved. Use the control charts as part of the process control system for identifying trends so that potential problems can be corrected before they occur. Make decisions concerning mix modifications based on analysis of the results provided in the control charts. The Quality Control Plan shall indicate the appropriate action to 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

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) (NA for Superpave)

Flow, 0.01 inches (NA for Superpave)

Asphalt content, % deviation 0.4 0.5 0.2 0.3 from JMF target; plus or minus value.

Laboratory Air Voids, % .2 .4 .1 .3 Deviation from JMF target, Plus or minus value

In-place Mat Density, % TMD .5 1.0 .4 .8 (Per sub-lot average) Deviation from specification limits

In-place Joint Density, No specific action and suspension

3.11 MATERIAL ACCEPTANCE

Testing for acceptability of work will be performed by an independent laboratory hired by the Government, this does not relieve the contractor of his own materials testing requirements designated by this specification. The Contractor shall forward test results daily to the Project Manager. 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 [_1 Phase____], a sub-lot will be equal to [1 day of production]. Material, grade, and surface smoothness acceptability determinations will be made on the lot as a whole.

3.11.1 Sub-lot Sampling

Two random mixture samples for determining laboratory air voids, theoretical maximum density, and for any additional testing the Project Manager desires, will be taken from a plate paved over by the paving machine each sub-lot. All samples will be selected randomly by the project manager, or using commonly recognized methods of assuring randomness conforming to ASTM D 3665, or employing tables of random numbers or computer programs. Laboratory air voids will be determined from three laboratory compacted specimens of each sub-lot 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

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.