415COLD CENTRAL PLANT RECYCLING

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4-80SECTION 415 – COLD CENTRAL PLANT RECYCLING

415.01DESCRIPTION . This work shall consist of cold central plant recycling (CCPR) of the existing

pavement surface, including generating RAP material from the project or other sources, adding additional asphalt emulsion or foamed asphalt binder, Portland cement, virgin aggregate, and mixing and repaving of the material to the depths, lines, an d grades shown on the Plans. Excess recycled material not used in the CCPR process will become the property and responsibility of the Contractor.

415.02MATERIALS . Materials shall meet the requirements of the following subsections:

Portland Cement ................................ ................................ ................................ ......... 701.02 Performance -Graded Asphalt Binder ................................ ................................ ......... 702.01 Anionic Emulsified Asphalt ................................ ................................ ....................... 702.02(a) Cationic Emulsified Asphalt ................................ ................................ ...................... 702.02(b) Aggregate for Bituminous Concrete Mixtures ................................ ........................... 704.10 Recycled Asphalt Pavement ................................ ................................ ...................... 704.22(a) Water ................................ ................................ ................................ .......................... 745.01 Emulsified asphalt for CCPR, when used, shall be type HFMS -2, HFMS -2h, HFMS -2s, CSS -1, CSS -1h, MS-2h, or as recommended by the Contractor as a result of the design criteria of this specification and approved by the Engineer. Foamed asphalt binder for CCPR, when used, shall be unmodified and grade 58S -28, unless otherwise specified in the Contract. The CCPR shall meet the gradation requirements of Table 415.0 2A for extracted aggregate ( AASHTO T 30, dry) taken from the pulverized material. TABLE 415.02A – EXTRACTED AGGREGATE GRADATION Sieve Designation Percentage by Mass (Weight) Passing Square Mesh Sieves 1-1/2 inch (37.5 mm) 100 1 inch (25.0 mm) 90 – 100 No. 4 (4.75 mm) 30 – 70 No. 200 ( 0.075 mm) 0 – 12

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4-81The CCPR shall be free of any materials not generally considered to be asphalt pavement. If the processed

material does not meet the gradation requirements as specified, additional virgin aggregates shall be added at a rate such that the blended mixture co nforms to the gradation requirements specified in Table 415.02A . Additional virgin aggregate shall meet the requirements of Subsection 704.10(a) and Subsection

704.10(b) , except that sand equivalent is not required

415.03EQUIPMENT

crushing, or screening the processed bituminous material and any virgin material, foamed asphalt or emulsion, and Portland cement into a homogeneous mixture. The mixing equipment shall be equipped with belt scales to accurately proportion the additives, adjusted by the moisture content of the processed RAP and aggregate. The belt scale shall be verified for accuracy at each new location prior to mix production and shall be verified during production at the request of the Enginee r. The method of depositing the mixed material shall be such that segregation does not occur. Any additional equipment used by the Contractor beyond th at specified below shall be approved by the Engineer based on its suitability to produce results meeting the specification requirements. Hauling equipment used for hauling the mixture shall meet the requirements of Subsection

406.05(a)

Pavers shall meet the requirements of Subsection 406.05(b) .

required uniform density, full depth, while the mixture is in a workable condition. A pneumatic - tired roller shall perform the initial rolling after the emulsion initially breaks (indicated by color change from brown to black). At a minimum, the following rollers shall be used:

Rollers shall have a width of not less t han 65 inches. Tires on pneumatic rollers shall be evenly inflated and matched in size and profile so as to maximize compactive effort.

415 4-82 415.04 CONSTRUCTION REQUIREMENTS .

content of 1.0% was used to estimate the required Portland cement tonnage for this work. Agency personnel and equipment shall be allowed free and full access to the project site at n o additional compensation due the Contractor to allow for any and all sampling required to assess compliance with the provisions of this specification. The Contractor will afford the Agency all traffic control operations and provide means to extract samples as requested to achieve this effort. The residual asphalt and cement content used in production may vary throughout the project and be adjusted by the Contractor based on the results of QC testing or other variables as identified by the Agency or the C ontractor to maintain an optimized finished product. Emulsion or foamed asphalt binder, water, processed bituminous pavement, virgin aggregate, and Portland cement shall be added in the proportions necessary to meet mix design requirements and verified b y tank checks performed in accordance with the minimum quality control frequencies. Portland c ement may be introduced in dry form or as a cement slurry.

415.0 4B, or Table 415.04C , as applicable for the type of asphalt being used. TABLE 415.04A – EMULSIFIED ASPHALT USING THE MARSHALL STABILITY TEST Criteria Test Method Requirement Ratio of residual asphalt to cement -- 3 to 1, min. Stability value, dry subset AASHTO T 245 1,500 lbf , min. Retained stability, wet/dry subsets AASHTO T 245 0.70, min. TABLE 415.04B – EMULSIFIED ASPHALT USING THE INDIRECT TENSILE STRENGTH TEST Criteria Test Method Requirement Ratio of residual asphalt to cement -- 3 to 1, min. Indirect tensile strength, dry subset AASHTO T 283 45 psi , min. Tensile strength ratio AASHTO T 283 0.70, min.

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4-83TABLE 415.04C – FOAMED ASPHALT

Criteria Test Method Requirement Ratio of residual asphalt to cement -- 3 to 1, min. Foamed asphalt expansion ratio -- 8 times , min. Foamed asphalt half -life -- 6.0 sec. , min. Indirect tensile strength, dry subset AASHTO T 283 45 psi , min. Tensile strength ratio AASHTO T 283 0.70, min.

asphalt or foamed asphalt, Portland cement, and blended aggregate if appropriate. To obtain material to conduct mix designing, the Contractor shall sample exi sting pavement to represe nt the recycled aggregates that would be expected to result from the milling process. A minimum of four samples representative of the quarter points of the entire length of the project shall be taken . If stockpiled RAP is to be used, the stockpile will be sampled from 4 locations and combined to generate a representative sample. The Contractor shall develop and submit a material sampling plan for review and approval by the Agency a minimum of 5 working days prior to obtaining CCPR mix design samples. At a minimum, the sampling plan shall include the number of samples, location of samples, and the method of sampling and backfilling. The mix design shall also consider shoulder areas to be widened beyond existing edge of pavement such that the recycled bitumin ous pavement is full width to the lines and grades shown in the Plans. When emulsified asphalt is used, AASHTO PP 86 shall be the method used to develop a mix design in accordance with AASHTO MP 31 , except only meeting the specified design requirements in Table 415.04A or Table 415.04B , as applicable. The job mix formula (JMF) shall contain the percent passing each sieve, emulsified asphalt type and content as a percent of total CCPR material, and cement content as a percent of total CCPR material. When foamed asphalt is used, AASHTO PP 94 shall be the method used to develop a mix design in accordance with AASHTO MP 38 , except only meeting the specified mix design requirements in Table 415.04C . The job mix formula shall contain the percent passing each si eve, foamed asphalt content as a percent of total CCPR material, and cement content as a percent of total CCPR material.

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4-84A minimum of 10 working days shall be allowed for evaluation of the submitted mix design. A

copy of all test data used in developing the mix design, including graphs, shall be submitted with the mix design. The established job -mix formula is valid until a change is made in aggregate source, cement content, or emulsion source. No change in the job -mix formula may be made without the written approval of the Engineer. The Engineer may approve changes in the design’s job -mix formula or discontinue use of the design if placement, finishing, or compaction characteristics are determined to be unsatisfactory.

where the shoulders are widened, to the specified grade and slope. The bituminous mixture shall be placed and finished with the specified equipment, shall be struck o ff in a uniform layer to the full width required and of such depth that each course, when compacted, shall have the required thickness, and shall conform to the grade and elevation specified. The finished surface shall be of uniform texture and evenness an d shall not show tearing, shoving, or pulling of the mixture. In areas where irregularities or unavoidable obstacles make the use of mechanical placing and finishing equipment impracticable, the mixture shall be spread, raked, luted, and compacted by hand methods.

workable state. The CCPR material shall be finished within a grade tolerance of ± 1/2 inch, provided that this deviation is not maintained for a distance l onger than 50 feet, and provided that the required crown or superelevation is maintained. Deviations in the finished surface shall not exceed ± 3/8 inch in any direction using a 10 foot minimum straight edge. Any repairs required to correct surface deviations are at the Contract or’s expense using Agency approved material and methods. The CCPR shall be compacted to 98% to 102% of the target maximum density (TMD). If two out of three consecutive density test results are outside of the allowable range, the Contractor will be required to construct a new test section to establish an updated TMD. If the Engineer determines that the TMD is apparently incorrect, as evidenced be being achieved with little or minimal compactive effort, then the Engineer will req uire a new test section to establish a new TMD.

415 4-85 (f) Curing and Stability . The CCPR may be opened to traffic after achieving the target density and after the material is determined to be stable by the Engineer. Hot mixed bituminous concrete pavements shall not be placed until the CCPR material has been allowed to cure and the free moisture content is reduced to a maximum of 1.5% every 1,000 feet per lane or as directed by the Engineer. The Engineer may waive the 1.5% free moisture content in such cases that the CCPR has been

open to a cure period of 14 days or more.

The required density shall be achieved and maintained until a wearing course pavement has been

placed. Any additional compaction effort or repair of imperfections in the CCPR material shall be

performed as directed by the Engineer at no additional cost to the Agency. As an alternative for

the purpose of protecting the CCPR from damage due to traffic, the Engineer may approve the use

of an emulsified asphalt fog seal after the placement of the CCPR and prior to the placement of

any hot mix bituminous pavement.

is below 50°F, when the overnight temperatures are expected to be below 50°F, when the

temperature of the existing roadway surface is below 50°F, when the weather is foggy or rainy, or

when weather conditions or predicted weather conditions are such that proper mixing, spreading,

and compacting of the recycled material cannot be accomplished.

The placement of CCPR shall not be performed prior to May 1 st or after September 15 th .

When it is in the public interest for servicing traffic, the Engineer may adjust the ambient air or

existing roadway surface temperature requirements or extend the dates of the recycling season.

415.05QUALITY CONTROL

quality control sampling and testing and operate in accordance with an approved QC plan. Prior

to performing any CCPR production, the Engineer or the Contractor may request a pre-recycle

conference to discuss the recycling schedule.

The Contractor shall sample, test, and evaluate the CCPR process in accordance with the

procedures and minimum frequencies specified in Table 415.05A.

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TABLE 415.05A – MINIMUM QUALITY CONTROL FREQUENCIES

Test or Action Frequency Test Method

Density 1 per 1,000 feet per lane AASHTO T 355 or

ASTM D2950

Air temperature 4 per day at even intervals Verified thermometer

Surface temperature At beginning and end of

each day’s operation Verified thermometer

Yield for cement and

emulsion 2 per day at even intervals Tank check

RAP moisture 1 per day AASHTO T 217 or

AASHTO T 255

Aggregate moisture 1 per day AASHTO T 217 or

AASHTO T 255

In-place moisture content 3 per day

AASHTO T 217,

AASHTO T 255,

AASHTO T 310, or

ASTM D7830

Gradation and asphalt

content of final product 1 per day

AASHTO T 30 (dry),

AASHTO T 164, or

AASHTO T 308

Density testing shall be the average of three points across the lane (transverse) for each testing

location.

Gradation failures shall require the Contractor to take action to adjust the process to achieve

compliant material. Additional virgin aggregate added to correct gradation shall meet the

requirements of Subsection 704.10(a) and Subsection 704.10(b), except that sand equivalent is not

required.

Quality control records shall include all sampling events, testing events, and process changes with

accurate time and location data. The Contractor shall submit QC records and summaries to the

Engineer by 1:00 p.m. on the next working day. The Contractor shall make all test results,

including randomly sampled densities, available to the Engineer onsite and on request.

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The Contractor shall cease recycling operations whenever one of the following occurs:

by the Engineer.

Recycling operations shall not resume until the Contactor and the Agency agree on the corrective

action to be taken.

a minimum of 14 calendar days prior to initiating CCPR operations and shall not commence CCPR

operations until the QC plan is accepted by the Engineer.

The QC plan shall address any items that affect the quality of the recycling process including, but

not limited to, the following:

shall list their past experience on CCPR projects. They shall:

involved with the acceptance activities of the project.

construction operations.

the QC plan.

conducting quality control and inspection activities to implement the QC plan. There may

be more than one QCT on a project. They shall:

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minimum of two years of experience in quality control activities in field

construction operations.

Transportation Training and Certification Program (NETTCP) for Soils and

Aggregate Inspector, or an equivalent regional program.

the QC plan.

controlling the recycling process, quality control and inspection activities at the mixing

plant to implement the QC plan. They shall:

minimum of two years of experience in quality control activities in field

construction operations.

the QC plan.

submitted to the Engineer as requested and copies of all project QC testing shall be

submitted on such dates that a biweekly estimate from the Agency is intended to be

processed.

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free of debris or contamination that could adversely affect the finished product, and

the type of release agent used (if required).

recycling and curing in inclement weather, avoiding damage from haul trucks,

material yield monitoring, methods to ensure that segregation is minimized,

longitudinal joint construction, procedures to determine the maximum rolling and

placing speeds based on field quality control, and achieving the best possible

smoothness.

necessary corrective action.

CCPR, and through the project as needed.

The Contractor shall construct a control section to assure the Engineer that the Contractor’s

equipment and procedures are suitable for the work specified and establish the target maximum

density and moisture content. The rolling pattern shall be determined from buildup, when the

density readings show an increase in dry density of less than 1 pcf for the final four roller passes

of each roller.

The average of a minimum of 10 tests taken throughout the control section after the buildup is

complete shall be used to determine the TMD. If agency personnel are available, their values shall

be included in the average, or used to establish the density gauge offsets, as directed by the

Engineer.

The control section shall be full lane width and a minimum of 500 feet long, or as approved by the

Engineer. No further recycling shall be performed until all aspects of the control section and the

TMD are approved by the Engineer. The Contractor shall use the same equipment for building

both the accepted test sections and performing the CCPR work on the project unless equipment

substitution is approved by the Engineer.

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The Engineer may require an additional test section and additional process control sampling to

investigate the suitability of substituted or changed equipment.

If the control section does not meet the requirements of this specification, or the target density is

not determined from buildup testing, then the Contractor shall modify the procedure and either

construct another test section or reconstruct the original test section until suitable results are

obtained.

415.06METHOD OF MEASUREMENT. The quantity of Cold Central Plant Recycling of the depth

specified to be measured for payment will be the number of square yards of existing pavement which has

been recycled in an acceptable manner as determined by actual surface measurements of the lengths and

widths of the recycled area as shown on the Plans or as directed by the Engineer. No additional

compensation will be made for overlapping areas.

The quantity of Aggregate for CCPR to be measured for payment will be the number of tons used in the

complete and accepted work.

The quantity of Portland Cement for CCPR to be measured for payment will be the number of tons of

material in place in the complete and accepted work, as determined from the load tickets or other method

as approved by the Engineer.

The quantity of Emulsified Asphalt for CCPR and Foamed Asphalt for CCPR to be measured for payment

will be the number of hundredweight used in the completed and accepted work.

415.07BASIS OF PAYMENT. The accepted quantity of Cold Central Plant Recycling of the depth

specified will be paid for at the Contract unit price per square yard. Payment will be full compensation for

performing the work specified and for furnishing all labor, materials, tools, equipment, and incidentals

necessary to complete the work. Any additional RAP material, not generated from the project, required to

meet the project volume of Cold Central Plant Recycling will not be paid for separately but will be

considered incidental to Cold Central Plant Recycling.

The accepted quantity of Aggregate for CCPR will be paid for at the Contract unit price per ton. Payment

will be full compensation for furnishing and placing the material specified and for furnishing all labor,

tools, equipment, and incidentals necessary to complete the work.

Payment for the furnishing of emulsified asphalt fog seal will be made under the appropriate Section 404

pay item in the Contract.

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The accepted quantity of Portland Cement for CCPR will be paid for at the Contract unit price per ton.

Payment will be full compensation for furnishing and placing the material specified and for furnishing all

labor, tools, equipment, and incidentals necessary to complete the work.

The accepted quantity of Emulsified Asphalt for CCPR and Foamed Asphalt for CCPR will be paid for at

the Contract unit price per hundredweight for the specified material applied. Payment will be full

compensation for furnishing, transporting, and placing the material and for furnishing all labor, tools,

equipment, and incidentals necessary to complete the work.

Payment will be made under:

Pay Item Pay Unit

00 Cold Central Plant Recycling, 2 Inch Depth .............................................Square Yard

50 Cold Central Plant Recycling, 2.5 Inch Depth ..........................................Square Yard

00 Cold Central Plant Recycling, 3 Inch Depth .............................................Square Yard

50 Cold Central Plant Recycling, 3.5 Inch Depth ..........................................Square Yard

415.0400 Cold Central Plant Recycling, 4 Inch Depth .............................................Square Yard

50 Cold Central Plant Recycling, 4.5 Inch Depth ..........................................Square Yard

00 Cold Central Plant Recycling, 5 Inch Depth .............................................Square Yard

415.5100 Aggregate for CCPR .................................................................................Ton

415.5200 Portland Cement for CCPR .......................................................................Ton

415.5300 Emulsified Asphalt for CCPR ...................................................................Hundredweight

415.5400 Foamed Asphalt for CCPR .......................................................................Hundredweight

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4-92SECTIO N 417 – BITUMINOUS CRAC K SEALING

417.0 1 DESCRIPTION . This work shall consist of furnishing and placing crack -sealing material in the cracks of existing bituminous concrete pavement. 417.0 2 MATERIALS . Materials shall meet the requirements of the following subsections: Joint Sealer, Hot Poured ................................ ................................ ............................ 707.0 2(a) The Contractor shall provide the Engineer with a copy of the material manufacturer’s recommendations pertaining to heating, application, and reheating prior to the beginning of operations or the changing of materials. 417.0 3 EQUIPMENT . Equipment shall mee t the approval of the Engineer and shall always be maintained in working condition.

feet of air per minute with a minimum pressure of 90 psi at the nozzle . The compressor shall be equipped with traps that will keep the compressed air free of any oil or water.

squeegees, and any other tools which may be req uired to accomplish the work .

between the inner and outer shells shall be filled with a suitable heat transfer oil or substitute having a flash point of not less than 531°F . The kettle shall be equipped with a satisfactory means of agitating the joint sealer . This may be accomplished by continuous stirring with mechanically operated paddles or by a continuous circulating gear pump attached to the heatin g unit. The melting kettle shall be equipped with a thermostatic control calibrated between 200°F and 550°F . The kettle shall be mounted on rubber tires and be equipped with a metal shield beneath the firebox to protect the pavement.

or heated hose . The nozzle shall distribute the material as called for on the Plans or this specification . The Contractor shall backflush the hose and applicator wand any time the application of sealant has been delayed for a period greater than 15 minutes. A pressure regulator shall be provided to regulate pressure at the nozzle . A bypass line into the holding tank is required for use when the nozzle is shut off.