The National Academies Press

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From page 8... ... Pavement Condition Functional condition of an existing pavement describes roadway features that meet the users' need for ride quality (smoothness) , safety (polishing, bleeding/flushing, friction) Read the entire page →
From page 9... ... TABLE 5 AGENCY RESPONSES FOR PRECONSTRUCTION FIELD TESTING FOR IN-PLACE RECYCLING PROJECTS Preconstruction Field Testing: Before construction, I typically use: Preconstruction Work States HIR CIR FDR Condition Distress Survey AR, AZ, CA, CO, FL, ID, IA, KS, KY, MD, MO, MT, NC, NE, NY, TX, VT, WA AZ, CA, CO, CT, DE, ID, IA, KS, MD, MN, MO, MT, NE, NH, NV, NY, OR, RI, SD, UT, VA, VT, WA, WI, WV AR, AL, CA, CO, CT, DE, GA, ID, IA, MD, MN, MO, MT, NE, NH, NV, OR, SC, SD, TX, UT, VA, VT, WI, WY Ride Quality (smoothness measurements) AR, AZ, CA, CO, FL, GA, ID, KS, MD, MT, VT, WA AZ, CA, CO, ID, MD, MN, MT, NH, NV, UT, VA, VT, WA, WY AL, CA, CO, MD, MN, NH, NV, UT, VA, VT Both agencies and contractors rely on distress survey information when considering projects for recycling. Read the entire page →
From page 10... ... milling depths for FDR projects than agencies. This may represent more nonstate work on low traffic volume roadways by contractors. Read the entire page →
From page 11... ... Contractors are less likely than agencies to consider tight turns and steep grades as acceptable features for CIR projects. The majority of contractors with experience placing FDR projects feel comfortable using this process with any of the features listed in this survey. Read the entire page →
From page 12... ... noted that one of the advantages of CIR was the ability to use this process on projects with numerous entrances, side roads, and intersections because CIR would not result in raising the grade. TABLE 10 INFLUENCE OF ROADWAY GEOMETRIC AND FEATURES ON THE SELECTION OF IN-PLACE RECYCLING PROCESSES Question: I would consider recycling a roadway with: ADT Type of In-Place Recycling Used HIR CIR FDR Tight Turns (radius 12 m (<40 ft) Read the entire page →
From page 13... ... The survey explored preferences for recycling processes used in four general climate regions: • Cold and wet, • Cold and dry, • Hot and wet, and • Hot and dry. TABLE 12 AGENCY CLIMATE PREFERENCES FOR RECYCLING METHODS Question: Environmental Conditions: I would consider recycling on roadways in the following climate regions: Climate Climate conditions HIR CIR FDR Cold and Wet CA, GA, ID, IL, IA, KS, KY, MO, NC, NY, TX, VT, WA CA, DE, ID, IL, KS, KY, MN, MO, MT, NC, NH, NV, NY, RI, WI AK, CA, CO, DE, GA, ID, IL, KY, MN, MO, MT, ND, NH, NV, OR, SD, TX, WI, WY Hot and Wet AR, CA, CO, FL, GA, ID, IL, IA, KS, KY, MT, NC, NU, TX, VT, WA CA, CO, DE, ID, IL, IA, KS, KY, MT, NC, NH, NB, NY, RI, VA, VT, WA CO, DE, GA, ID, IL IA, KY, MD, MT, ND, NH, NV, OR, SC, SD, TX, VA, WY Cold and Dry AZ, CA, CO, GA, ID, IL, IA, KS, NY, TX, VT, WA AS, CA, CO, DE, ID, IL, KS, MT, NH, NV, NY, RI, SD, UT, VT, WA, WY CA, CO, DE, GA, ID, IL, IA, MK, MT, ND, NH, NV, OR, SD, TX, UT, VT, WY Hot and Dry AR, AZ, CA, CO, DC, FL, GA, ID, IL, IA, KS, MS, MT, NE, NY, TX, VT, WA AL, AR, AZ, CA, DE, FL, IL, IN, KS, MD, MO, NE, NJ, OR, SD, TX, UT, VA, VT, WA, WI, WY AL, AR, AZ, CA, CL, DE, FL, IL, MO, ND, NE, NJ, OR, RI, SD, TX, UT, VA, VT, WA, WI Read the entire page →
From page 14... ... Percentages are based on the number of agencies and contractors with experience using the specific recycling process. TABLE 13 RANKING OF CLIMATES THAT CAN INFLUENCE THE CHOICE OF IN-PLACE RECYCLING PROCESSES Climate HIR CIR FDR Cold/Wet F G VG Hot/Wet G G VG Cold/Dry G VG VG Hot/Dry VG VG VG P = Poor, lower than 10% agencies and contractor with experience. Read the entire page →
From page 15... ... properties, selecting materials, and providing mix designs for setting the job mix formulas. The information varies on the basis of the recycling process (Figure 12) Read the entire page →
From page 16... ... The use of GPR testing will likely increase as the technology becomes more widely available in the coming years because it can provide information quickly on layer thickness, presence of moisture, and sections of the project in need of different designs. TABLE 16 AGENCY TESTING FOR LAYER PROPERTIES Preconstruction Field Testing: Before construction, I typically use: Preconstruction Work States HIR CIR FDR Coring to Determine Thickness AK, AL, CA, CO, DE, GA, ID, IA, MD, MN, NC, ND, NE, NV, OR, SC, SD, TX, UT, VA, VT, WY AR, AZ, CA, CO, FL, GA, ID, IA, KY, MD, MO, MT, NE, NH, NV, NY, OR, RI, SD, UT, VA, VT, WA, WY AK, AL, CA, CO, CT, DE, GA, ID, IA, MD, MN, MO, MT, NE, NH, NV, OR, SC, SD, TX, UT, VA, WY Boring to Check Depth of Base and HMA CO, ID, KS, MD, MO, MT, TX, WA CO, CT, DE, ID, KS, MD, MO, MT, NH, NV, OR, SD, UT, VA, WA, WI AR, AZ, CA, CO, FL, ID, IA, KS, KY, MD, MO, MT, NC, NE, NY, TX, VT, WA FWD Testing AR, AZ, CO, FL, ID, MD, NC, NE, TX, VT, WA AZ, ID, MD, MN, NC, NE, NV, OR, RI, SD, UT, VA, VT, WA, WY AK, AL, CA, ID, MD, MN, MT, NC, NE, NV, OR, SD, TX, UT, VA, VT GPR Testing MT, TX MN, MT MN, MT, TX, AK Fewer field tests are conducted on HIR projects by contractors and agencies compared with CIR and FDR projects (Figure 13) Read the entire page →
From page 17... ... TABLE 18 AGENCY RESPONSES FOR PRECONSTRUCTION LABORATORY TESTING FOR IN-PLACE RECYCLING PROJECTS Preconstruction Laboratory Testing: Before construction, I typically determine: Laboratory Testing States HIR CIR FDR Aggregate Gradations of Cores or Millings AR, CA, FL, ID, KS, KY, MF, NC, NE, TX, WA CA, CT, DE, ID, KS, MD, MN, ND, NH, NY, RI, SD, UT, VT, WY AK, AL, CA, DE, GA, IA, MD, MN, SD, UT, VT Application Rates of Binders or Other Additives CA, CO, IA, KS, MD, NE, NY, TX, WA CA, CO, CT, IA, KS, MD, MN, NE, NH, NY, SD, UT, VT, WY AL, CA, CO, GA, ID, IA, MD, MN, NE, SC, UT, VT, WY Binder Content of Cores or Millings AR, CA, FL, ID, KS, KY, MD, NC, NE, TX, WA CA, CO, CT, ID, KS, MD, MN, ND, NE, NH, NY, WY AL, CA, GA, MD, MN, WA Material Properties of Any Liquids, Stabilizers, Rejuvenators, Additives, or Admixtures to Be Added CA, CO, FL, GA, IA, KS, MD, NC, NE, NY, TX, WA CA, CO, IA, KS, MD, NE, SD, UT, WY AL, CA, CO, GA, IA, MD, NE, TX, UT, VT, WY Percent Fines of Millings CA, FL, ID, KY, MD, NC, NE, TX CA, ID, MD, UT, VT, WY AK, CA, ID, IA, MD, NE, UT Recovered Binder Properties from Cores or Millings CA, FL, GA, KY, MD, NC, NY, TX, VT, WA CA, MD, WY AK, CA, MD Contractors conduct more tests before construction than the agencies (Figure 15) Read the entire page →
From page 18... ... Asphalt Binders Asphalt binders used in recycling processes can be typical paving-grade asphalts or emulsions: TABLE 20 REQUIREMENTS FOR CATIONIC EMULSIFIED ASPHALTS (based on ASTM D2387-05; D977-05; Oregon DOT 2010) Type Medium Setting Slow Setting Grade HFMS-2 HFMS-2s HF-150 CMS-2S CSS-1 CSS-1h Min Max Min. Read the entire page →
From page 19... ... Asphalt -- Foamed Asphalt One method of adding fresh binder to cold recycling processes (CIR and FDR) is to foam it during the mixing process in the recycling train. Read the entire page →
From page 20... ... The amount of new HMA needed for a recycling job is small compared with the typiTABLE 22 ASTM D4552 CLASSIFICATIONS FOR HOT MIX RECYCLING AGENTS (ASTM D4552 2009) Test ASTM Test Method RA 1 RA 5 RA 25 RA 75 RA 250 RA 500 Min Max Min Max Min Max Min Max Min Max Min Max Viscosity at 140°F, cSt D 2170 or D 2171 50 175 176 900 901 4,500 4,501 12,500 12,501 37,500 37,501 60,000 Flash Point, COC, °F D92 425 -- 425 -- 425 -- 425 -- 425 -- 425 -- Saturates, wt% D 2007 -- 30 -- 30 -- 30 -- 30 -- 30 -- 30 Tests on residue from RTFO or TFO oven 325°F (D 2872 or D 1754) Read the entire page →
From page 21... ... Tests Test Method ER-1 ER-2 ER-3 Min Max Min Max Min Max Testing on emulsion Viscosity, 50°C, SSF D224 100 20 450 20 450 Sieve, % D6933 0.1 0.1 0.1 Storage Stability, 24 h, % D6930 1.5 1.5 1.5 Residue, by Distillation, % D6997 65 65 65 Dilution -- ReportA Specific Gravity D70 Report Report Report CompactibilityB varies Report Report Report Testing on residue from distillation Viscosity, 60°C, cSt D2170 50 200 30 30 Saturates, % D2007 30 Solubility in Trichloroethylene D2042 97.5 97.5 97.5 On residue from distillation after RTFOC Penetration, 4°C, 50 g 5 s D5 75 200 5 75 RTFO, Weight Change, % D2872 4 4 4 Notes: AER-1 shall be certified for dilution with potable water. BThis specification allows a variety of emulsions, including high-float and cationic emulsions. Read the entire page →
From page 22... ... Moisture resistance is improved by a reduction in the permeability of the base materials. Asphalt emulsions, a mixture of asphalt cement, water, and an emulsifying agent, improve the strength and moisture resistance of the base material, soften the aged asphalt binder in the RAP, and reduce shrinkage cracking seen with cement and lime stabilizers. Read the entire page →
From page 23... ... . TABLE 25 SUMMARY OF USES FOR ADDITIVES AND STABILIZERS IN RECYCLING PROCESSES Additive or Stabilizer CIR FDR Moisture Resistance Freeze/ Thaw Resistance Rut Resistance Layer Stiffness Rate of Set Control Minimize Raveling Mechanical Stabilization Chemical or Bituminous Stabilization Calcium Chloride X X X Portland Cement X X X X X X Lime X X X X X Quicklime X X X X X Fly Ash X X X Limestone Fines X X X X Fibers X X X Asphalt X X X X X X Recycling Agents X X X X X In summary, additives and stabilizers need to be selected on the basis of their ability to improve key material and mix properties. Read the entire page →
From page 24... ... . TABLE 26 AGENCY AND CONTRACTOR RESPONSES TO MIX DESIGN METHODS Mix Design Testing: Before construction, I or my contractor design our recycled mixes based on the following method: Mix Design Methods Agency Responses HIR CIR FDR Do Not Do Mix Designs CA, ID, IA, MO, VT, WA CA, DE, ID, IA, NC, NH, NV, RI, SD, VT, WA, WI CT, DE, ID, MN, MT, NC, NH, NV, NY, SD, VT, WI Hveem -- -- -- Marshall AZ, KY, NE AZ, MN, NE, OR, VA, WY VA Superpave CO, KS, MO, ND, UT, VT CO, KS, MO, ND, UT, VA MD, MO, UT, VA Wirtgen -- VA AK, CA, IA, VA Other NY, TX CT, MT, NY AL, CO, GA, NE, NY, SD, WY Between 20% and 42% of the states do not develop mix designs for recycling projects (Figure 20) Read the entire page →
From page 25... ... Combinations of additives and stabilizers such as emulsions and cement can be designed with CIR mix designs or by using geotechnical tests. Regardless of the mix design method used, there was general agreement that there is a lack of established curing times, temperatures, or humidity conditions. Read the entire page →
From page 26... ... . TABLE 27 MIX DESIGN PRACTICES Mix Design Methods HIR CIR FDR No Formal Design Sometimes Sometimes* Read the entire page →
From page 27... ... Other design considerations noted in the FIGURE 22 Information used for structural design approaches by agencies and contractors. Percentages are based on the number of agencies and contractors with experience using the specific recycling process. Read the entire page →

From page 8...

... Pavement Condition Functional condition of an existing pavement describes roadway features that meet the users' need for ride quality (smoothness) , safety (polishing, bleeding/flushing, friction)