3-35 pavement, regrading and compacting existing gravel base, proces sing, mixing, testing, placing, and compacting, excess material relocation, and for al l incidentals necessary to complete the work. Payments will be made under: Pay Item P a y U n i t
310.23 3 inch Plant Mixed Recycled Asphalt Pavement S q u a r e Y a r d
310.24 4 inch Plant Mixed Recycled Asphalt Pavement S q u a r e Y a r d
310.25 5 inch Plant Mixed Recycled Asphalt Pavement S q u a r e Y a r d
310.26 6 inch Plant Mixed Recycled Asphalt Pavement S q u a r e Y a r d
SECTION 311 - COLD IN-PLACE RECYCLED ASPHALT PAVEMENT (Traveling Pugmill)
311.01 Description The Contractor shall construct a Cold In-place Recycled
Pavement base course in accordance with the Contract documents and in reasonably close conformity with the lines, grades, thicknesses, and typical cro ss sections shown on the plans or as established by the Resident. This work will consist of mi lling 3 to 7 inches of existing bituminous pavement, pulverizing and sizing the millings, the a ddition of emulsified asphalt and Portland Cement or hydrated lime to the proportions specifi ed, the mixing and placement of the mixture full width as required in the contract , (including shoulders) and compacting the mixture as one continuous operation to the lines , grades and thicknesses indicated on the plans or as established by the Resident. Exces s recycled material not used in the CIP process will become the property of the State. MIX DESIGN
311.02 Composition of Mixture The Contractor shall provi de the Resident with a
proposed mix design a minimum of two weeks prior to commencing work. The proposed mixed design shall include the emulsified asphalt binder applic ation percentage, type and supplier, the percentage of Portland Cement or hydrated lime to be added, and the percentage of any supplemental aggregates to be added. a The aim for air voids in the final product is 8 to 11%. b The Contractor may add water as needed to the sized material to facilitate uniform mixing and compaction. c Included in the mix design will be the product information fr om the supplier of the asphalt emulsion binder and any product information regarding t he Portland cement or hydrated lime. 3-36 d The Contractor will be responsible for deciding and conductin g investigative work to determine the properties of the existing in place bituminous mi xes which the Contract documents do not describe. Any cores or laboratory testing the contractor performs to establish the recycled mix design will be incidental to the Col d in Place Recycle pay item and not paid for separately. A copy of all test results on the pavement samples shall be included with the mix design. The addition of hydrated lime, or Portland Cement at 0.50% to 1 .0% by weight is required and is to be included in the mix design criteria. Emul sion, water, aggregate, cement shall be added in percentage by weight and verified by tank che cks according to the Quality Control Plan. Cement or lime may be added in dry form or in a s lurry. MATERIALS 311.030 Pulverized Material Recycled bituminous pavement, after milling and sizing, will meet the following gradation requirements: Sieve Size % Passing Limits 1 ½ in 100 1 in 95-100 311.031 Emulsified Asphalt The emulsified asphalt binder shall be a high float asphalt emulsion grade HFMS-2, or a cationic slow-set grade CSS -1H, that meets the requirements of Section 702.04. 311.032 Portland Cement The Portland Cement shall be Typ e 1 or 2 that meets the requirements of AASHTO M85. 311.033 Hydrated Lime The hydrated lime shall meet the r equirements of AASHTO M216. 311.034 Added Aggregates New aggregate, if required by t he contract or job mix, shall meet the requirements of Section 411.02 - Untreated Aggre gate Surface Course. 311.035 Added Water Water shall be clean and free from d eleterious concentrations of acids, alkalis, salts or other organic or chemical substance s. EQUIPMENT 311.040 Equipment The existing bituminous pavement shall be recycled in a continuous operation using a recycling train consisting of the following major components. The recycling equipment and operations may be combined onto one unit: 311.041 Mainline Cold Milling Machine The unit shall be self-propelled with a down cutting drum, or an approved up-cutting drum, and be autom ated to continuously adjust and maintain treatment depth and cross slope. The cuttin g drums shall be a minimum 3-37 of 10 ft in width, with the ability to add 1 or 2 ft extensions to the drum or have hydraulically extendable milling heads with a 12 ft width. Dust suppression systems are required. The unit should be capable of recycling the pavement for the entire lane width to the required dimensions in one pass. 311.042 Shoulder Cold Milling Machine If required, the s houlder unit shall have a minimum cutting drum of 6.5 ft in width or equal to the should er width to be recycled. This unit shall precede the larger mainline milling machine to remov e existing pavement off any existing paved shoulders. The material will be placed via a lif t conveyor onto the existing mainline roadway surface to be incorporated and processed by th e mainline milling machine. 311.043 Screening and Sizing Unit This unit shall be cap able of reducing and sizing the recycled asphalt pavement to the specified gradations prior to mixing with the asphalt emulsion, and cement or lime additives. Oversize particles shal l not be included in the final mix. The manufacture of excessive waste through the screening p rocess will be prohibited. If more than 5% of the recycled material is screened off as was te, the contractor will be required, at no additional compensation, to re-introduce the ma terial ahead of the train to be reprocessed. 311.044 Portable Mixing Unit The unit shall be capable o f producing a uniform, thoroughly mixed, cold mix asphalt product. The material feed system to the mixing unit shall be equipped w ith a computer controlled weigh bridge that will determine the mass of recycle d material, by weight, being deposited into the mixing unit prior to the addition of the emu lsified liquid asphalt. The scales shall be calibrated to the manufacturer’s tolerance at t he start of the contract and will be checked for conformance to Section 401.074. This mixing unit shall be of a dual shaft pugmill design, equip ped with a metering device which will continuously meter and maintain the amount of emulsified asphalt being added to the process to a tol erance of + 0.25% of the total, b y weight. The emulsion control unit shall be equipped with a flow meter a nd a total delivery meter. A positive displacement pump capable of accurately metering the required quantity of emulsion down to a rate of 4 gal/min into the recycled material is required. The pump shall be equipped with a positive interlock system tha t will shut off automatically when material is not present in the mixing chambe r. Each mixing machine shall be equipped with a meter capable of r egistering the rate of flow and total delivery of the emu lsion introduced into the mix ture. The unit shall be designed to either deposit the mixed product onto the roadway in a sized windrow, or capable of de positing the product directly in to a paver hopper. 3-38 Only tankers with a capacity exceeding 2500 gal shall be used t o supply the recycling machine with bitumen. No leaking tanker will be permitted on t he job site. In addition, each tanker shall be equipped with the following:
a.A thermometer to show the temperature of the contents in the bottom third of the tank.
b.Insulation to retain heat. c. A calibrated dipstick marked at intervals of no more than 25 gal, for measuring the contents of the tank. 311.045 Placing Equipment If a pick up conveyor is to be utilized to transfer the windrow into a paver hopper, the pickup conveyer machine shall be capable of removing the entire windrow down to the underlying material. The paver utili zed to place the recycled product shall conform to Section 401.09. 311.046 Compaction Equipment Compaction equipment shall meet the requirements of Standard Specification 401, subsection 401.10 – Rollers, wit h the following additional requirements: a Minimum compaction equipment shall consist of two 10 ton doub le drum steel wheel vibratory rollers; b and one 20 ton pneumatic tired roller. The minimum allowable tire pressure shall be 85 psi. The Contractor shall furnish a suitab le tire gauge for determining air pressure in the tires. Additional equipment may be required in sufficient numbers and weight to obtain the required compaction. CONSTRUCTION REQUIREMENTS
311.05 Removal of Existing Pavement The existing pavemen t surface, including
cracks, shall be visibly free from all foreign matter before re cycling commences. The Contractor is responsible for removing any deleterious material s or crack sealants decided to be an interference with the col d recycle process. In areas wher e paved shoulders exist, the shoulders will be milled just ahead of the mainline milling and removed material incorporated into the recycle process. When areas of the pavement surface are inaccessible because of the physical constraints of the equipment, the pavement shall be removed by other means and replaced by an approved source of hot mix asphalt.
311.06 Weather and Temperature Limitations The Cold In-P lace Recycled process
shall be performed when: a CIP operations will be allowed between May 15 th and September 15th inclusive in Zone 1 - Areas north of US Rout e 2 from Gilead to Bangor and no rth of Route 9 from 3-39 Bangor to Calais. CIP operations will be allowed between May 1st and September 30th inclusive in Zone 2 - Areas s outh of Zone 1 including the US Ro ute 2 and Route 9 boundaries. b The atmospheric temperature, as determined by an approved the rmometer placed in the shade at the recycling location, is 50 0F and rising. c When there is no standing water on the surface. d During generally dry conditions, or when weather conditions a re such that proper pulverizing, adding, mixing, and c uring can be obtained using p roper procedures, and when compaction can be accomplished as determined by the Reside nt. e When the surface is not frozen and when overnight temperature s are expected to be above 32 0F. f Wind conditions as such that the spreading of lime or cement on the roadway ahead of the recycling machine will not adversely affect the operatio n. 311.061 Curing No new hot mix asphalt pavement or additi onal layers of CIP shall be placed on the recycled asphalt pavement until a curing perio d of (4) four days has elapsed. The curing period starts once the CIP process has been completed in the roadway. When weather conditions are unfavorable, the curing period may be extended by the Resident.
311.07 Surface Tolerances The completed recycled pavemen t surface will be
shaped, compacted, smoothed and true to required line and grade . Deviations in the finished surface shall not exceed ⅜ in in any direction using a 10 ft mi nimum straight edge. Any repairs required to correct surface deviations are at the contr actor’s expense using Department approved material and methods. The Contractor shall protect the completed surface from damage caused by construction vehicles and equipment. The recycled pavement surface shall be protected and closed to traffic until it is determined that surface damage no longer oc curs when a test vehicle is passed over it. The contactor is responsible for determining wh en the completed surface is suitable for traffic loading without damage. Any repairs to cor rect damage will be at the contractor’s expense. 311.071 Joints Joints shall be constructed in accordance with Section 401.17.
311.08 General Procedure Mainline milling is to be accom plished full width, one
pass, and the material will be conveyed into a sizing and crush ing unit. Once sized, the material is conveyed to a mixing unit where the specified perce ntage of asphalt emulsion, Portland Cement, or lime is introduced for the coating and mixi ng process. The thoroughly mixed recycled product will either be deposited, (a) in a windrow behind the mixing unit and picked up via a conveyor, or (b) directly c onveyed into a paver hopper 3-40 for laydown. The mix will be lai d full width, including shoulde rs where paved shoulders existed, to the specified grade and slope. Water shall be used as necessary to assist the compaction effor t. TESTING REQUIREMENTS
311.09 Quality Control The Contractor shall operate in ac cordance with the
approved Quality Control Plan (QCP) to assure a product meeting the contract requirements. The QCP shall meet the requirements of Section 106.6 - Acceptan ce and this Section. The Contractor shall not begin recycling operations until the Depar tment approves the QCP in writing. Prior to performing any recycling process, the Department and t he Contractor shall hold a Pre-recycle conference to discuss the recycling schedule, typ e and amount of equipment to be used, sequence of operations, and traffic control. A copy o f the QC random numbers to be used on the project shall be provided to the Resident. All field and plant supervisors including the responsible onsite recycling process supervisor s hall attend this meeting. The QCP shall address any items that affect the quality of the Recycling Process including, but not limited to, the following:
a.JMF(s). b. Make and type of rollers including weight, weight per inch o f steel wheels, and average contact pressure for pneumatic tired rollers.
c.Make and type of equipment in recycling train. d. Testing Plan. e. Laydown operations including j oint construction, yield monit oring, procedures for avoiding recycling and curing in i nclement weather, methods to ensure that segregation is minimized, and pro cedures for mix design modific ation.
f.Methods for protection the finished product from damage and procedures for any necessary corrective action.
g.Method of grade checks. h. Examples of Quality Control forms. i. Name, responsibilities, and qualifications of the Responsibl e onsite Recycling Supervisor experienced and knowledgeable with the process.
j.Method for calibration/verification of density gauge. k. A note that all testing will be done in accordance with AASH TO and MaineDOT/ACM procedures.
l.Description of the Cold In- place recycled verification pr ocedure. The Project Superintendent sha ll be named in the QCP, and the r esponsibilities for successful implementation of the QCP shall be outlined. The Contractor shall sample, test, and evaluate the cold in-pla ce recycling process in accordance with the following minimum frequencies: 3-41 MINIMUM QUALITY CONTROL FREQUENCIES Test or Action Frequency Test Method Density 1 per 1000 ft / lane ASTM D 2950 Air Temperature 4 per day at even intervals Surface Temperature Beginning and end each day Yield of all materials (daily) 1 per 1000 ft/ lane New Aggregate Gradations 2 per day AASHTO T 30 The Contractor shall submit all QC test reports and summaries i n writing, signed by the appropriate technician, and present them to the Department’s on site representative by 1:00
P.M. on the next working day, except when otherwise noted in th e QCP due to local restrictions. The Contractor shall make all test results, inclu ding randomly sampled densities, available to the Department onsite. During the Cold in-place recycli ng procedure the Contractor sha ll take verification samples of the recycled material prior to adding the emulsion a t a rate of one per 26,000 lane ft, or a minimum of one per project. The samples will mixed to the proportions specified in the job mix formula, and tested by t he Contractor for conforman ce to the contract specifications. Penalties for QCP non-compliance will be in accordance with Sta ndard Specification106.4.6 The Contractor shall cease recycling operations whenever one of the following occurs: a The computed yield differs from the approved Job Mix Formula by 10% or more. b The Contractor fails to follow the approved QCP. c The Contractor fails to achieve 98% density after corrective action has been taken. d The Contractors verificati on samples show the air void conten t of the recycled product is outside the 8-11% range. e The finished product is visually defective, as determined by the Resident. Recycling operations shall not resume until the Contactor and t he Department agree on the corrective action to be taken.
311.10 Control Section The contractor shall assemble all items of equipment for the
recycling operation on the first day of the recycling work. The Contractor shall construct a control section for the project at a location approved by the R esident. The contractor shall have on site a pavement engineer expert in CIP work to direct c onstruction of the control section, advise on suitability of mixed material, bitumen dispe rsion within the mixed 3-42 material, moisture control within the mixed material, compactio n and surface finish. The control section is required to:
a.Demonstrate that the equipment and processes can produce rec ycled layers to meet the requirements specified in these special provisions.
b.Determine the effect on the grading of the recycled material by varying the forward speed of the recycling machine and the rotation rate of the mil ling drum.
c.Determine the sequence and manner of rolling necessary to ob tain a target TMD. The Contractor and the Department will calibrate their respective g auges at this time. The control section shall be at least 750 ft in length of a fu ll lane-width (or a half- roadway section width). The Contractor shall repeat the control section process until p arameters of the material properties conform to the requirements specified herein and as directed by the Resident. If a control section fails to meet the requirements outlined in this Special Provision, the contractor will be required to take corrective action to remedy the test strip defect to the satisfaction of the Resident at no additional cost to the Depar tment. The repeated process of the control section construction shall be done at the Contracto r's expense. The corrective method shall be determined by the Contractor, as directed by th e Resident. Quality Assurance densities of the recycled material will be de termined by the Department using the nuclear method. The test strip section wil l be rolled as directed until the nuclear density readings show an increase in dry density of less than 1 pcf for the final four roller passes. This density will be used as the target de nsity for the recycled material. The remaining full depth recycled material shall be compacted t o a minimum density of 98% of the target density as determined in the control section. ACCEPTANCE TEST FREQUENCY Property Frequency Test Method In-place Density 1 per 2000 ft / lane AASHTO T 310
311.11 Measurement and Payment The accepted quantity of Cold in Place Recycled
Pavement will be measured and paid for by the square yard compl ete and in place to the limits specified in the contract documents. The unit price shal l include all materials, equipment, supervision, and labor and tools incidental thereto. No additional payment will be made for hot mix required to repl ace material that cannot be compacted to the specified density, or used to replace damag ed or raveled sections. The removal of existing pavement, placement, and compaction of any hot mix asphalt required in areas that are inaccessible due to the limitations of equipment shall be paid for as Cold in place Recycle mix per square yard. Payment to be made under: 3-43 Pay Item Pay Unit
311.33 3 inch Cold in-Place Recycled Asphalt Pavement Square Yard
311.34 4 inch Cold in-Place Recycled Asphalt Pavement Square Yard
311.35 5 inch Cold in-Place Recycled Asphalt Pavement Square Yard
4-1 Chapter 4 DIVISION 400 - PAVEMENTS SECTION 401 - HOT MIX ASPHALT PAVEMENT
401.01 Description The Contractor shall furnish a uniformly bl ended, homogeneous
mixture placed as one or more cour ses of Hot Mix Asphalt Paveme nt (HMA) on an approved base in accordance with the contract documents and in reasonably close conformity with the lines, grades, thickness, and typical cross sections shown on the plans or established by the Resident. The Department will accept this w ork under Quality Assurance provisions, in accordance with these specifications and the req uirements of Section 106 – Quality, the provisions of AASHTO M 323 except where otherwise noted in sections 401 and 703 of these specifications, and the MaineDOT Policies and Procedures for HMA Sampling and Testing.
401.02 Materials Materials shall meet the requirements specifi ed in Section 700 -
Materials: Asphalt Cement 702.01 Aggregates for HMA Pavement 703.07 RAP for HMA Pavement 703.08 HMA Mixture Composition 703.09
401.03 Composition of Mixtures The Contractor shall compose th e Hot Mix Asphalt
Pavement with aggregate, Performance Graded Asphalt Binder (PGA B), and mineral filler if required. HMA shall be designed and tested according to AASHTO R35 and the volumetric criteria in Table 1. The Contractor shall size, uniformly grad e, and combine the aggregate fractions in proportions that provide a mixture meeting the gra ding requirements of the Job Mix Formula (JMF). Unless otherwise noted in Speci al Provision 403 - Hot Mix Aspha lt Pavement, the design, verification, Quality Control, and Accept ance tests for this mix will be performed at 65 gyrations. TABLE 1: VOLUMETRIC DESIGN CRITERIA Design ESAL’s (Million
s.Required Density (Percent of G mm) Voids in the Mineral Aggregate (VMA)(Minimum Percent) Voids Filled with Binder (VFB) (Minimum %) Fines/Eff. Binder Ratio Nominal Maximum Aggregate Size (mm) Ninitial Ndesign N max 25 12.5 9.5 4.75 <0.3 <91.5 96.0 <98.0 13.0 14.0 15.0 16.0 16.0 70-80 0.6-1.2 0.3 to <3 <90.5 65-80 3 to <10 <89.0 65-80* 10 to <30 > 30 *For 9.5 mm nominal maximum aggregate size mixtures, the maximu m VFB is 82. For 4.75 mm nominal maximum aggregate size mixtures, the maximum VFB is 84.
Source: Maine Standard Specifications for Road and Bridge Construction, 2020 Edition. Pages 252–261 of 817.