This section was truncated when BuildSpec ingested it, so the text below stops short of the printed section and may be missing subsections, tables or pay items. Treat it as an excerpt and read the source PDF for the complete, authoritative text.
Open the official NM source PDF ↗SECTION 412: HOT IN-PLACE RECYCLING OF ASPHALT PAVEMENT (REMIX ING METHOD)
412.1 Description
This Work consists of recycli ng the existing in-place asphalt surface in a multi-step process of cleaning, heating, m illing, rejuvenating (if require d), spreading, and leveling. This Work also consists o f placing and compacting the new HMA/WMA ov er the recycled surface. The Contract may require the Contractor to blend recycled Mater ial with an asphalt- rejuvenating agent.
412.2 Materials
412.2.1 Rejuvenating Agent
The Contractor shall provide an agent that will rejuvenate the existing Roadway’s binder properties. The existing Roadway ’s asphalt Material shall be e xtracted, recovered, and combined with a virgin asphalt binder per AASHTO M 323, Appendi x A such that the combination of the rejuvenating agent with the existing Roadway asphalt binder will meet the full AASHTO M 320 requirements for the required PG asphalt grad e in the approved mix design.
412.2.2 Hma/Wma
The Contractor shall provide the HMA Material and mix design i n accordance with Section 416, “Minor Paving;” Se ction 423, “Hot-Mix Asphalt (HMA ) (Major Paving);” or Section 424, “Warm Mix Asphalt (WMA).”
412.3 Construction Requirements
412.3.1 Equipment
412.3.1 1 General
At the Pre-Construction Conference, the Contractor shall: 1. Notify the Project Manager of the necessary types of Equipme nt; 2. Deliver the Equipment to the Pr oject in time for the Project Manager’s evaluation; 3. Demonstrate the rate, depth, and recycling operations on a R oadway test section before beginning production operations; and 4. Submit a Quality Control Plan in accordance with the most re cent Department’s Contractor Quality Control Guidelines for the Project Manager’s approval. If Equipment or recycling operations do not meet requirements, the Contractor shall correct or replace the deficiency.
412.3.1 2 Heating Units
The Contractor shall ensure the heating units can heat the exi sting asphalt pavement high enough to mill the Material to the minimum specified depth without the following results: 1. Breaking aggregate particles; 2. Charring the existing asphalt; or 3. Producing undesirable pollutants. Section 412: Hot In-Place Recycling of Asphalt Pavement (Remixing Method) Pa ge 182 The Contractor shall apply the heat under an enclosed or shiel ded hood. The Contractor shall not heat the pavement surface with a direct flame.
412.3.1 3 Milling Units
The Contractor shall: 1. Use milling units that can mill to the specified depth; 2. Equip the units with automatic height controls to clear util ity manholes and other obstructions in the pav ement surface; and 3. Use units with enough power to mill through high spots and c reate a leveled surface.
412.3.1 4 Rejuvenating Agent Storage Unit
The Contractor shall use a thermostatically-controlled storage unit to maintain the rejuvenating agent at a constan t, Supplier-specified temperatur e.
412.3.1 5 Metering Unit
The Contractor shall: 1. Use a unit that can uniformly apply the rejuvenating agent t o the milled Material. The unit shall incorporate a meter for continuous quantity veri fication; 2. Vary the applied amount in direct proportion to the recyclin g system’s operating speed and synchronize with the amount of Material milled; and 3. Not vary the rejuvenating agent’s application tolerance by m ore than 0.5% of the specified application rate.
412.3.1 6 Blending Unit
The Contractor shall use a twin-shaft pugmill unit that can un iformly mix the milled Material, rejuvenating agent, and virgin HMA/WMA.
412.3.1 7 Spreading and Leveling Unit
The Contractor shall use a unit with automatic grade controls capable of spreading and leveling the Material uniformly over the specified surfaces.
412.3.1 8 Compaction Equipment
The Contractor shall use compaction Equipment in accordance wi th Section 423.3.4.4, “Compaction Equipment.”
412.3.2 Construction Details
412.3.2 1 Cleaning of Existing Pavement Surface
Before beginning hot in-place recycling, the Contractor shall clean the existing pavement surface of non-asphalt Material s by blading and brooming or use methods approved by the Project Manager.
412.3.2 2
Heating, Milling, and Processing Section 412: Hot In-Place Recycling of Asphalt Pavement (Remixing Method) Pa ge 183 The Contractor shall heat, mill, and process the in-place asph alt surface in a uniform manner to the widths and depths in accordance with the Plans. The Contractor shall control the heat to assure a uniform heat penetration without the follo wing results: 1. Differential softening of the pavement; 2. Breaking of the aggregate particles; 3. Charring of the asphalt; or 4. Producing undesirable pollutants. If required, the Contractor shall: 1. Uniformly apply the rejuvenating agent to the milled Materia l before the addition of new HMA or WMA; 2. Determine the actual amount of rejuvenating agent needed to address field conditions and to optimize the pr operties of the in-place pavem ent; and 3. Uniformly mix the milled Material, rejuvenating agent, and H MA or WMA to produce a homogeneous mixture.
412.3.2 3 Placing and Compacting
The Contractor shall uniformly spread and level the recycled m ixture to the width, grade, and slope specified in the Plans. Immediately after leveling t he recycled Material, compact the Material in accordance with Sec tion 423.3.5, “Placement Operati ons.”
412.3.2 4 Temperature Requirements
The Contractor shall ensure the temperature of the asphalt Mat erials immediately behind the laydown machine is between 225 °F and 300 °F.
412.3.2 5 Joints
The heating unit shall heat a minimum of four (4) inches beyon d the width of recycling. The Contractor shall construct j oints in accordance with Sectio n 423.3.5.4, “Joints.”
412.3.2 6 Debris and Waste Material Disposal
The Contractor shall dispose of debris and waste Material in a n environmentally safe manner at locations approved by the Project Manager.
412.3.2 7 Weather Limitations
The Contractor shall not perform hot in-place recycling of asp halt pavement when the Roadway surface is wet or when weather conditions prevent the p roper handling, finishing, and compacting of the asphalt mixture.
412.3.2 8 Surface Tolerance
The Contractor shall provide a compacted surface in accordance with Section 423.3.5.5, “Surface Tolerances.”
412.3.2 9 Plan Surfacing Depths
The Contractor shall monitor and record the depth of the compa cted recycled pavement Material (including new HMA Mate rial, if specified) during the placement operations. The Section 412: Hot In-Place Recycling of Asphalt Pavement (Remixing Method) Pa ge 184 Contractor shall perform this task in accordance with the Depar tment’s Minimum Testing and Acceptance Requirements and as approved by the Project Manager. The Project Manager will address deficiencies of more than 0.5 inches by: 1. Accepting the in-place compac ted thickness at an adjusted pr ice; or 2. Rejecting the in-place mixed Material and requiring the Cont ractor to remove and replace.
412.3.3 Contractor Quality Control
412.3.3 1 Contractor Quality Control for Materials
The Contractor shall provide new HMA or WMA Materials in accor dance with Section
423.3.6 1, “Contractor Quality Control;” except take random tes t samples from the HMA/WMA
windrow before the Material goes through the paver.
412.3.3 2 Contractor Quality Control for Compaction
See Section 423.3.6.1.2, “Contractor Quality Control for Compa ction.”
412.3.3 3 Suspension of Operations
See Section 423.3.6.3, “Acceptance.”
412.3.3 4 Project Verification Testing
The Contractor shall place new HMA Materials in accordance wit h Section 423.3.6.4, “Independent Assurance Testing” or WMA Materials in accordance with Section 424.3.6.4, “Independent Assurance Testing.”
412.3.4 Department Quality Assurance
412.3.4 1 Department Quality Assurance Testing for HMA Mix
New HMA Materials shall meet the requirements of Section 423.3 .6, “Sampling and Testing,” with the exception th at the Department will base Acce ptance on random test samples taken from the HMA windrow before the Material goes thr ough the paver. New WMA Materials shall meet the require ments of Section 424.3.6, “Samp ling and Testing,” with the exception that the Department will base Acceptance on random te st samples taken from the WMA windrow before the Material goes through the paver.
412.3.4 2 Department Quality Assurance Testing for HMA or WMA C ompaction
The Department will test in accordance with Section 423.3.6, “ Sampling and Testing” or
424.3 6, “Sampling and Testing.” The target density is a mean density of at least 93% of the
theoretical maximum density. The Project Manager will grant an exception to the target if the Contractor can demonstrate that the target density is not reaso nably obtainable because of the conditions of the existing Pave ment Structure or Subgrade M aterials. If the Department grants this exception, the Contractor shall construct a Roadway test strip and develop a HMA compacti on process to obtain the highes t possible target density based on an approved roller’s density gain per pass, in accorda nce with Section 423.3.4.4, “Compaction Equipment.” The Contractor shall not begin paving operations (except for the Roadway test strip) until the Project Manager approves the proc ess. The in-place density shall not exceed 98% of the theoretical maximum density or be m ore than three percent (3%) Section 412: Hot In-Place Recycling of Asphalt Pavement (Remixing Method) Pa ge 185 below the target density. If a lot’s mean density does not mee t this density requirement, the Project Manager may do the following: 1. Require the Contractor to remove and replace the defective l ot of HMA or WMA at no additional cost to the Department; or 2. Accept the HMA or WMA Material and pay the Contractor 50% of the Bid Item Unit Price. If the Project Manager determines that the mean measured densi ties are consistently higher, not exceeding 93% of the theoretical maximum density, o r lower than the current lot’s target density, the Project Manager may establish a new Accepta nce lot on the Project.
412.3.4 3 Department Quality Assurance Testing for HMA/WMA Smoo thness
If the Contract requires two (2) or more layers of new HMA/WMA Material, place in accordance with Section 401, “Pavement Smoothness Measurement.” For the purposes of this section, Hot Recycled Insitu Material is not defined as HM A/WMA.
412.4 Method of Measurement
The Department will measure HMA in accordance with Section 423 .4, “Method of Measurement” or WMA in accordanc e with Section 424.3, “Method o f Measurement.”
412.5 Basis of Payment
The Department will pay for new HMA Material in accordance wit h Section 423.5, “Basis of Payment” or WMA Material in accordance with Section 424.5, “ Basis of Payment.” Pay Item Pay Unit Hot In-place Recycling of Asphalt Pavement Square Yard Rejuvenating Agent Gallon
412.5.1 Work Included in Payment
The Department will consider as included in the payment for th e pay item(s) listed in this section and will not measure or pay separately for the followin g Work: 1. Recycling existing in-place a sphalt surface in a multi-step process of cleaning, heating, milling, and rejuvenati ng (if required), spreading and leveling; 2. Placing and compacting new HMA/WMA over recycled surface; 3. Shipping/Delivery of new HMA/WMA to Project site; and 4. Development of the Contractor Quality Control Plan in accord ance with Section 902, “Quality Control.” Section 413: Single-Machine Hot In-Place Surface Repaving Page 186