1、Standard Specification for Materials for Cold Recycled Mixtures with Emulsified Asphalt AASHTO Designation: MP 31-171Technical Section: 2a, Emulsified Asphalts Release: Group 3 (August 2017) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 W
2、ashington, D.C. 20001 TS-2a MP 31-1 AASHTO Standard Specification for Materials for Cold Recycled Mixtures with Emulsified Asphalt AASHTO Designation: MP 31-171Technical Section: 2a, Emulsified Asphalts Release: Group 3 (August 2017) 1. SCOPE 1.1. This standard covers requirements for component mate
3、rials and asphalt mixtures for cold in-place recycling (CIR) or cold central plant recycling (CCPR) to produce a job mix formula. 1.2. This standard specifies minimum quality requirements for cold recycled mixtures and the emulsified asphalt. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 85, Port
4、land Cement M 140, Emulsified Asphalt M 208, Cationic Emulsified Asphalt M 216, Lime for Soil Stabilization M 320, Performance-Graded Asphalt Binder PP 86, Emulsified Asphalt Content of Cold Recycled Mixture Designs T 245, Resistance to Plastic Flow of Asphalt Mixtures Using Marshall Apparatus T 283
5、, Resistance of Compacted Asphalt Mixtures to Moisture-Induced Damage 2.2. ASTM Standard: D7196, Standard Test Method for Raveling Test of Cold Mixed Emulsified Asphalt Samples 2.3. Other Document: LTPP Seasonal Asphalt Concrete Pavement Temperature Models, LTPPBind 3.1 3. TERMINOLOGY 3.1. cold in-p
6、lace recycling (CIR)the on-site recycling process to a typical treatment depth of 75 to 100 mm (3 to 4 in.), using a train of equipment (tanker trucks, milling machines, crushing and screening units, mixers, pavers, and rollers) and an emulsified asphalt with or without a combination of additives (l
7、ime, cement, aggregate), generating and reusing 100 percent of the milled material, with the resulting pavement serving as a base layer overlaid with a surface treatment or asphalt mixture overlay. 2017 by the American Association of State Highway and Transportation Officials. All rights reserved. D
8、uplication is a violation of applicable law.TS-2a MP 31-2 AASHTO 3.2. cold central-plant recycling (CCPR)the process in which the aspha lt recycling takes place at a central location using a stationary cold mix plant. The resulting pavement serves as a base layer overlaid with a surface treatment or
9、 asphalt mixture overlay. 3.3. reclaimed asphalt pavement (RAP)removed and/or processed pavement materials containing asphalt binder and aggregate. 4. SIGNIFICANCE AND USE 4.1. This standard may be used to select and evaluate materials for cold recycled mixture designs. 4.2. Specifying an emulsified
10、 asphalt alone for CIR or CCPR may not be satisfactory in producing a good-performing mixture. The specifications here, along with the mix design described in PP 86, have been used successfully in many projects. 5. RAP REQUIREMENTS 5.1. Process pavement cores according to PP 86 to produce two of the
11、 three gradation bands shown in Table 1. Alternatively, if experience has demonstrated consistent field gradations from milling, process the RAP to that gradation. Table 1RAP Gradation Requirements Sieve Size Fine Gradation Medium Gradation Coarse Gradation Percent Passing 31.5 mm (1.25 in.) 100 100
12、 100 25 mm (1 in.) 100 100 85100 19 mm (3/4in.) 95100 8596 7592 4.75 mm (No. 4) 6575 4065 3045 600-m (No. 30) 1535 414 17 Note 1Adjustment of the gradation bands to local conditions and cons truction equipment is recommended. The selected gradations shall be chosen to match the expected field gradat
13、ion as closely as possible, with the exception that a greater top size on the project is expected. Gradations on a project will vary from sample to sample. Slight adjustments in the field to the design emulsified asphalt content are often necessary to obtain optimum mixture performance. Performing t
14、he mix design at two gradations can determine an acceptable range of emulsified asphalt contents for the project. 5.2. Ensure RAP meets agency requirements for at least an asphalt base mixture. 6. EMULSIFIED ASPHALT AND ADDITIVE REQUIREMENTS 6.1. Emulsified Asphalt: 6.1.1. For engineered emulsified
15、asphalt, use LTPPBind (version 3.1), the nearest weather station to the project, 98 percent reliability, and the depth to the top of the CIR layer in the pavement structure to select the low temperature PG requirements from M 320 for the residue of the emulsified asphalt. A spread of 89 or less betw
16、een the high PG and the low PG temperatures is normally acceptable in choosing a base asphalt for the emulsified asphalt. Determine the other properties of the emulsified asphalt to meet mixture requirements. 6.1.2. For cationic emulsified asphalt, use CSS-1 or CSS-1h from M 208. 2017 by the America
17、n Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-2a MP 31-3 AASHTO 6.1.3. For anionic emulsified asphalt, use HFMS-2, HFMS-2h, or HFMS-2s from M 140. Note 2For example, for an overlay thi ckness of 50 mm (2 in.) determi
18、ne the cold temperature requirement at 98 percent reliability at that thickness as the minimum requirement for the base asphalt of the emulsified asphalt. For a surface treatment, use 0 mm. The low temperature requirement can be more conservative in temperate climates or for a CIR layer with a thick
19、 overlay. For example, if LTPPBind determines a cold temperature minimum of 10C (14F) in a temperate climate and the predominant grade for that climate is 16C, then a base asphalt for the emulsified asphalt of 16C (3F) or 22C (8F) is acceptable. Note 3A general recommendation for an y of the recycli
20、ng emulsified asphalts is a minimum residue of 64 percent. 6.2. Other Additives: 6.2.1. If quicklime or hydrated lime is used it shall meet the requirements of M 216. If Type I or II cement is used it shall meet the requirements of M 85. 6.2.2. Ensure additional aggregate (i.e., add stone) meets age
21、ncy requirements for at least an asphalt base mixture. 7. DESIGN REQUIREMENTS 7.1. The cold recycled mixture design at optimum emulsified asphalt content shall meet the requirements specified in Table 2 when prepared in accordance with PP 86. Table 2Cold Recycled Mixture Design Requirements Test Met
22、hod (choose one) Criteria Property Indirect Tensile Strength Test Indirect Tensile Strength, dry subset, T 283 Minimum 310 kPa (45 psi) Cured Strength Tensile strength ratio, T 283 Minimum 0.70 Resistance to Moisture Induced Damage Raveling Test of Cold Mixed Bituminous Mixtures, ASTM D7196 Maximum
23、7.0% loss Resistance to Raveling Ratio of Residual Asphalt to Cement Minimum 3.0:1.0 Prevent Rigid Behavior Marshall Stability Test Marshall Stability, dry subset, T 245 Minimum 5,560 N (1,250 lbs.) Cured Stability Retained Marshall Stabilitya, T 245 Minimum 0.70 Resistance to Moisture Induced Damag
24、e Standard Test Method for Raveling Test of Cold Mixed Emulsified Asphalt Samples, ASTM D7196 Maximum 7.0% loss Resistance to Raveling Ratio of Residual Asphalt to Cement Minimum 3.0:1.0 Prevent Rigid Behavior aRetained Marshall stability = average of conditioned Marshall stability/average of dry Ma
25、rshall stability 8. REFERENCES 8.1. Basic Asphalt Recycling Manual, Asphalt Recycling and Reclaiming Association and FHWA-HIF-14-001, Annapolis, MD. 9. KEYWORDS 9.1. Cold recycled; cold in-place recycle; CIR: cold central plant recycle; CCPR; emulsified asphalt; reclaimed asphalt pavement; RAP. 1This provisional standard was first published in 2017. 2017 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.
