Recycling and Reclamation of Asphalt Pavements Using In-Place Methods (2011)

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58 APPENDIX B Examples of Specifications Missouri specification for 1 inch HIR Wisconsin FDR specification Maine FDR specification

59 Missouri HIR 1-inch http://www3.modot.mo.gov/JOBSPEC2.NSF/172856ff65ca19dc862567bb004c65cd/b416bfcb85fed19c8625745800 5ded53?OpenDocument 1.0 Description. This work shall consist of hot in-place recycling of the existing asphalt surface with a virgin hot mix overlay. 2.0 Material. All material shall be in accordance with Division 1000, Material Details, and specifically as follows: 2.1 The application rate of emulsified asphalt that is added to the recycled material shall be determined by the contractor prior to construction. The emulsified asphalt shall conform to the following set of requirements: Asphalt Emulsion Testa EA-300P ARA -1P Min. Max. Min. Max. Viscosity: SSF @ 50ºC 100 400 — — SSF @ 25ºC — — 15 100 Storage Stabilityb Test, 24 hour, percent — 1 — 1 Sieve Test, 850 µm mesh (No. 20), percent — 0.3 — 0.1 Distillation: Oil distillate by volume of emulsion, percent — 3 — 2 Residue from distillationc, percent 65 — 60 65 Test on Residue from Distillation Penetration: 25ºC, 100 g, 5 seconds 300 — — — 4ºC, 100 g, 5 seconds — — 150 250 Ductility, 4ºC, 5 cm/minute, cm 25 — 100 — Ashd, percent — 1 — — Float Test at 60ºC, sec. 1200 — — — Elastic Recoverye, percent 58 — — — Asphaltenes ASTM D3279, D4124 or D6560 — — — 15 a All tests shall be performed in accordance with AASHTO T 59 except as noted. b In addition to AASHTO T 59, upon examination of the test cylinder, and after standing undisturbed for 24 hours, the surface shall show no appreciable white, milky colored substance and shall be a homogeneous brown color throughout. c AASHTO T 59 shall be modified to maintain a 204°C ± 5 C maximum temperature for 15 minutes. d Percent ash shall be determined in accordance with AASHTO T 111, Ash in Bituminous Material. e Elastic recovery shall be determined as follows. Condition the ductilometer and samples to be treated at 10ºC. Prepare the brass plate, mold and briquet specimen in accordance with AASHTO T 51. Keep the specimen at the specified test temperature of 10ºC for 85 to 95 minutes. Immediately after conditioning, place the specimen in the ductilometer and proceed to elongate the sample to 20 cm at a rate of pull of 5 cm/min. After the 20 cm elongation has been reached, stop the ductilometer and hold the sample in the elongated position for 5 minutes. After 5 minutes, clip the sample approximately in half by means of scissors or other suitable cutting devices. Let the sample remain in the ductilometer in an undisturbed condition for one hour. At the end of this time period, retract the half sample specimen until the two broken ends touch. At this point note the elongation (x) in cm. Calculate the percent recovery by the following formula: % Recovery = (20 – X) × 100 20 2.2 The virgin hot mix asphalt shall conform to Section 403 of the standard specifications. When the virgin hot mix asphalt is placed simultaneously with the recycling operation, the point of sampling of virgin hot mix asphalt will be from the truck transports in accordance with AASHTO T168.

60 3.0 Equipment Requirements. 3.1 The contractor shall specify, to the engineer, the type of equipment intended for use. The contractor shall be required to demonstrate required rate, depth and satisfactory recycling operations on the roadway before being allowed to commence full operations. 3.2 The equipment shall be capable of uniformly heating the surface to a temperature high enough to remove excess moisture and allow dislodging of the material to a minimum depth of 1.0 inch, without breaking the aggregate particles. Heating shall be accomplished without burning or charring the existing pavement, without producing undesirable pollutants or damaging adjacent vegetation. 3.3 The emulsified asphalt shall be applied to the scarified material at a uniform rate as prescribed in the mix design or as directed by the engineer. Emulsified asphalt shall not vary more than 0.02 gallon per square yard from the mix design. The storage unit shall be able to maintain the emulsified asphalt within the temperature range specified by the supplier prior to mixing with the scarified material. 3.4 If the virgin hot mix asphalt overlay is applied simultaneously, the recycling equipment shall be capable of performing the functions of a bituminous paver as described in Section 403. 4.0 Construction Requirements. 4.1 The existing pavement surface to be recycled shall be cleaned of all dirt, fabric, oils, or any other objectionable materials before beginning the hot in-place surface repaving. Hot in-place recycling shall not take place when the roadway surface is wet, frozen or if the weather conditions prevent proper handling, finishing and compacting of the bituminous mixture. 4.2 The existing pavement surface shall be evenly heated, milled/scarified and reworked to a minimum depth of 1.0 inch from the lowest point in the pavement surface, and to the width shown on the plans. The surface temperature of the existing pavement shall not exceed 475°F, and the recycled mix temperature shall not be less than 225°F. The heating operation shall extend at least 2.0 inches beyond the width of scarification on both sides. On the second pass, the recycling shall overlap the previously recycled mat by at least 2.0 inches. 4.3 Virgin Hot Mix Asphalt 4.3.1 If the virgin hot mix asphalt overlay is to be placed in a continuous operation, the temperature of the recycled mix is to be maintained at a minimum of 225°F until the virgin mix is placed. 4.3.2 If the virgin hot mix asphalt overlay is to be placed with a separate operation, the following shall apply. The recycled asphalt mixture shall be compacted in accordance with Section 402. The recycled pavement shall be tacked in accordance with Section 407 prior to the virgin hot mix asphalt overlay. The virgin asphalt mixture shall be opened to traffic in accor- dance with Section 403. Traffic will be allowed to drive on the recycled mat; however, any damage to the recycled material shall be repaired by the contractor, at the contractor’s expense, prior to placing the virgin asphalt mixture. Rutting shall not exceed 3/8 inch. 4.3.3 The virgin hot mix asphalt mat shall be thoroughly and uniformly compacted in accordance with Section 403. Joint compaction shall be in accordance with Section 403. 5.0 Method of Measurement. 5.1 Final measurement of the completed hot in-place recycling will not be made except for authorized changes during con- struction, or where appreciable errors are found in the contract quantity. Where required, measurement of hot in-place recy- cling, complete in place, will be made to the nearest square yard. The revision or correction will be computed and added to or deducted from the contract quantity. 5.2 Measurement of emulsified asphalt to the nearest 10 gallons will be made as specified in Section 1015. If water is added to the emulsified asphalt, the quantity to be paid for will be determined prior to the addition of water.

61 5.3 Measurement of the virgin hot mix asphalt will be in accordance with Section 403. 6.0 Basis of Payment. 6.1 Hot in-place recycling will be paid for at the contract unit price per square yard, complete in place, and will be considered full compensation for all material, testing, labor, tools, equipment and appurtenances necessary to complete the work, includ- ing cleaning of existing pavement, heating, scarifying, mixing and relaying recycled material. 6.2 The accepted quantity of emulsified asphalt will be paid for at the contract unit price. No direct payment will be made for water added to the emulsified asphalt. 6.3 Payment for the virgin hot mix asphalt will be in accordance with Section 403. 6.4 No direct payment will be made for the asphalt emulsion used for the Tack Coat. 6.5 Hot in-place recycling, including the Asphalt Recycling Emulsion, shall be included in the smoothness adjustment in accordance with Section 403.

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63 Maine FDR Specification SECTION 305 - PREMIXED BITUMINOUS BASE Reserved SECTION 306 - RECLAIMED MATERIAL FOR STABILIZED BASE Reserved SECTION 307 - FULL DEPTH RECYCLED PAVEMENT 307.01 Description: This work shall consist of pulverizing a portion of the existing roadway structure into a homogenous mass, placing and compacting this material to the lines, grades, and dimensions shown on the plans or established by the Resident. 307.02 Pulverized Material: Pulverized material shall consist of the existing bituminous pavement and, if specified, a designated portion of the underlying gravel, pulverized, and blended into a homogenous mass. Pulverized material will be processed to 100% passing a 50 mm [2 in] square mesh sieve. Recycled material, if required, shall consist of material from the project or from off-site stockpiles that has been processed before use to 100% passing a 50 mm [2 in] square mesh sieve. Recycled material shall be conditionally accepted at the source by the Resident. It shall be free of winter sand, granular fill, construction debris, and other materials not generally considered bituminous pavement. DIVISION 200 -- EARTHWORK 307.03 Pulverizer: The pulverizer shall be a self-propelled machine, specifically manufactured for cold in-place recycled type work and capable of reducing the required existing materials to a size that will pass a 50 mm [2 in] square mesh sieve. The machine shall be equipped with standard automatic depth controls and must maintain a consistent cutting depth and width. The machine also shall be equipped with a gauge to show depth of material being processed. 307.04 Placement Equipment: Placement of the Full Depth Reclamation recycled material to the required slope and grade shall be done with an approved highway grader or by another method approved by the Resident. 307.05 Rollers: The Full Depth Reclamation recycled material shall be rolled with a vibratory pod/tamping foot roller with a minimum 1.4 m [54 in] diameter single drum. The drum shall have a minimum of 112 tamping feet, 75 mm [3 in] in height, and a minimum contact area per foot of 110 cm² [17 in²]. Final rolling shall be accomplished by a minimum 2.15 m [84 in] width single drum vibratory soil compactor. 307.06 Pulverizing: The entire depth of existing pavement shall be pulverized together with approximately 25 mm [1 in] of the underlying gravel into a homogenous mass. All pulverizing shall be done with equipment that will provide a homogenous mass of pulverized material, processed in-place, which will pass a 50 mm [2 in] square mesh sieve. 307.07 Weather Limitations: Full Depth Reclamation work shall not be performed when weather conditions are such that proper pulverizing, spreading, or compaction of the pulverized material cannot be accomplished. 307.08 Surface Tolerance: The complete surface of the Full Depth Reclamation course shall be shaped and maintained to a tolerance, above or below the required cross sectional shape, of 10 mm [• inch]. 307.09 Full Depth Reclamation: Procedure 50 mm [2 in] square mesh sieve and then shaped and compacted to the cross- slope and grade shown on the plans, typicals, or as directed by the Resident. 307.08 Surface Tolerance: The complete surface of the Full Depth Reclamation course shall be shaped and maintained to a tolerance, above or below the required cross sectional shape, of 10 mm [• inch]. 307.09 Full Depth Reclamation Procedure: 50 mm [2 in] square mesh sieve and then shaped and compacted to the cross- slope and grade shown on the plans, typicals, or as directed by the Resident.

64 Extra material will be added if required by the contract or Resident to restore cross-slope and/or profile grade before pulver- izing; locations will be shown on the plans or described in the construction notes. The Resident may add or delete locations while construction of the project is in progress. All extra material, whether shown on the plans or added, will meet the require- ments of Subsection 307.021 - New Aggregate and Additional Recycled Material, of this Special Provision. The Contractor will use recycled pavement to the extent it is available, in lieu of untreated aggregate surface course. The Contractor shall be responsible for re-establishing the existing profile grade as directed by the Resident. In areas where a variable gravel course is called for or required, the contractor shall pulverize, grade, and compact the existing pavement to allow for a consistent thickness of gravel. Density of the Full Depth Reclamation material will be determined by the Department using Nuclear Density Gauges. A 90 m [300 ft] section at the start of the pulverizing operations will be designated as the control section. The control section will be pulverized, have water added until testing indicates that optimum moisture has been obtained, and rolled as directed until the nuclear density readings show an increase in dry density of less than 16 kg/m³ [1 lb/ft³] for the final 4 vibratory roller passes. This density will be used as the target density for the recycled material. The remaining Full Depth Reclamation material shall be compacted to a minimum density of 98% of the target density as determined in the control section. 307.10 Method of Measurement: Full Depth Reclamation will be measured by the square meter [square yard]. 307.11 Basis of Payment: The accepted quantity of Full Depth Reclamation will be paid for at the contract unit price per square meter [square yard], complete in-place which price will be full compensation for furnishing all equipment and labor for pulverizing, blending, placing, grading, compacting, and for all incidentals necessary to complete the work. The addition of materials to restore profile grade and/or cross-slope in areas shown on the plans or described in the construc- tion notes will be paid separately under designated pay items within the contract. Payments will be made under: Pay Item Pay Unit 307.32 Full Depth Recycled Pavement Square Meter [Square Yard] (Untreated Maineline Travelway) 307.33 Full Depth Recycled Pavement Square Meter [Square Yard] (Untreated Shoulder)