Click for next page ( 5


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 4
4 IN-PLACE RECYCLING PROGRAMS IN THE UNITED few states have implemented HIR in recent years. Between STATES 14 and 18 states have more than 10 years of experience. The status of in-place recycling use across the United States was assessed using an online survey (Appendix A). The sur- TABLE 3 vey collected information from "choose all that apply" ques- AGENCY EXPERIENCE WITH IN-PLACED RECYCLING tions and open-ended requests for experiences. Responses METHODS were received from 45 states, although not all states had Question: Indicate how long you have been using each type of in-place experiences with in-place recycling (Table 1). A total of 34 recycling. of the 45 states and one Canadian providence (Ontario) indi- Years of Type of In-Place Recycling Used cated experience with both HIR and CIR projects, and 33 of Experience HIR CIR FDR the 45 indicated experience with FDR projects. Of the states <5 MO, NV DE, MO, NC, AL, DE, MO, with experience using HIR processes, HIR remixing was the ND, OR, UT NC, NY, VA, most frequently used (Table 2). WY 5 to 10 AZ, GA, IL IL, WY AK, CA, CO, GA, IL, IA, TABLE 1 MN NUMBER OF AGENCIES AND CONTRACTORS WITH EXPERIENCE* >10 AR, ON, CO, FL, ID, AZ, CA, CO, CA, CT, ID, IA, KS, KY, MD, CT, ID, IA, KS, MT, ND, NE, In-Place Recycling Method States with Contractors with MT, NC, NE, NY, MN, MT, NE, NH, NV, SC, Experience Experience TX, WA NH, NV, NY, SD, TX, UT, RI, SD, VT, VT, WI HIR 34 24 WA, WI CIR 34 24 We Don't AK, AL, CT, DC, DE, AK, AL, AR, AR, DC, RL, FDR 33 28 Use IN, MN, ND,NH, NJ, DC, FL, GA, IN, KS, KY, OR, RI, SC, SD, TN, IN, KY, NJ, NJ, OR, RI, *Agencies may use one or more of the methods. UT, VT, WI, WY SC, TN, TX TN TABLE 2 TYPE OF HIR USED BY AGENCIES TABLE 4 NUMBER OF LANE-MILES PER YEAR THAT ARE Question: What types of hot-in-place recycling do you use? RECYCLED BY EACH METHOD Type of HIR Used Question: Indicate the extent of your annual recycling program in Surfacing Repaving Remixing lane-miles. AR, CA, CO, FL, IL, AR, AZ, CO, FL, AR, AZ, CA, CO, FL, Lane-Miles Type of In-Place Recycling Used IA, KS, KY, MT, NC, KS, KY, MO, NC, ID, IA, KS, KY, MD, Recycled NE, NV, NY, TX, WY TX, WY MO, NC, NY, TN, TX, HIR CIR FDR VT, WA, WY AL, CO, CT, DE, AR, CA, CO, AZ, CA, CO, CT, GA, IL, IN, IA, FL, IL, IA, DE, ID, IL, IN, KS, MN, MO, MT, <50 KS, KY, MT, MN, MT, NE, NH, The Asphalt Recycling and Reclaiming Association NC, NE, NV, OR, RI, SD, TN, TX, NH, NY, OR, RI, (ARRA) membership list was used to identify contractors SD, TN, TX, UT, NY, TX, WY UT, VT, WA, WY VA, VT, WI to invite to complete the same survey. Of the membership list, 50 members were identified as contractors. In this case, AK, CA, ID, 50 to 100 CO MO, NE, NY ND, NE, NV companies providing materials and services for in-place >100 KS IA, NV, WI CA, SC recycling processes included asphalt contractors (e.g., for overlays) and aggregate producers. A total of 33 completed surveys were received. Responses were sorted by experience Figures 2 and 3 summarize state responses for the in-place with a specific in-place recycling process (Table 2). Not all recycling processes and the size of their annual programs. Also respondents had experience with all three methods. included in these figures is the maximum traffic level states consider acceptable for each process. These figures show that The years of experience with a recycling process (Table 3) the use of HIR and FDR is distributed across the United States. and the number of lane-miles typically paved per year were However, CIR is noticeably missing from use in the Southern evaluated (Table 4). The number of states with fewer than and Southeastern states. Reasons for the lack of use of CIR 10 years of experience represents the potential growth of in- in the Southern and Southeastern states are likely related to place recycling in the United States. FDR use has grown sub- weather conditions (e.g., humidity, temperature, rainfall) and stantially over the past decade, followed by CIR use. Only a should be identified in future research programs.

OCR for page 4
5 FIGURE 2 Use of HIR and CIR processes, size of programs (lane-miles per year), and maximum traffic levels acceptable for roadways. FIGURE 3 Use of FDR processes, size of programs (lane-miles per year), and maximum traffic levels acceptable for roadways.