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33 CHAPTER FOUR SPECIFICATIONS (Table 33). The use of a method specification tends to con- tradict state preferences for allowing the contractor to design the recycled mix and field adjust the designs as needed. TABLE 32 The content and extent of what is defined in a specifica- WRITTEN RESPONSES FOR USE OF WARRANTIES tion depend on the type of specification used by an agency. Regardless of the type of specification, they generally con- Warranty: Does your agency specify a warranty period for the different in-situ recycling processes. If so, what is the length of the warranty and tain the following sections: what type of assurance is required? Written Responses from Agencies Written Responses from 1. Description: Define the type of process to be used. Contractors Warranty--3 yr for rutting, cracking, 2. Materials: List all materials, specifications, test delaminations, raveling, and smooth- 1-yr warranty (4) methods, and mix composition to be used (method ness (FL) 2-yr warranty bond for 100% (2) specification). For end result, performance, and war- Warranty--5 yr period; bond 3-yr warranty bond for 100% required (WI) ranty specifications, identify who is responsible for 3-yr warranty materials; bonding Warranty--none these decisions. company has issues with 3 years (AL, AK, AZ, AR, CA, CO, CT, 4-yr warranty bond for 50% of DC, DE, GA, IA, ID, KS, KY, MO, construction cost; Performance 3. Construction Requirements: Identify key require- MT, NC, ND, NE, NV, NY, PA, SC, measures: fatigue, edge crack- ments for weather, surface preparation, equipment, SD, TX, UT, VA, WA, WY) ing, rutting, potholes; nothing material properties (e.g., moisture content of RAP, Warranty--under consideration HMA related (VT) mix temperatures) for method specifications. For No experience (3) Warranty--under development (IL) end result, performance, and warranty specifica- tions, identify who is responsible for these decisions. Information on minimum expectations for materi- TABLE 33 als, workmanship, and performance criteria is also STATE RESPONSES FOR TYPE OF SPECIFICATION USED included in this section. FOR RECYCLING PROJECTS Question: Specifications: What type of specifications does your 4. Method of Measurement: Define the units for each agency use? product or material to be measured (e.g., liquid RA in Surface Treatments Agency Responses gallons, cement slurry in tons, square yard of surface) HIR CIR FDR and how performance criteria are measured. Method AR, AZ, CA, AZ, CA, CO, CA, CO, DE, FL, IA, ID, KY, DE, FL, IA, GA, IA, ID, 5. Basis of Payment: Define payment for accepted quan- MD, MO, MT, ID, MN, MO, MD, MN, tities and include description of what is included in NC, NE, WI MT, NC, ND, MO, MT, NC, NE, NH, NV, ND, NE, NH, the units. OR, RI, SD, NV, OR, SD, UT, VA, VT, TX, UT, VA, State agency respondents were asked to identify the type WI, WY VT, WY of specifications used for in-place recycling projects. Method End Results CO, KS, KY, CO, IA, KS, AK, CO, GA, specifications are most frequently used (Table 32), which MO, TX MO, NV, ONT IA, MO, NV, SC indicates that the states define what materials will be used and how they will be placed. End result specifications are Performance CA, CO, DC, CA, DC, TN CA, DC, TN TN, TX used by some states, and neither performance nor warranty specifications are commonly used by states. The responses Warranty FL FL, WI NY to the use of warranties for recycling projects show that Note: Some states indicated they may use more than one type of only two states use warranties of 3- and 5-year durations specification.

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34 Contractors are likely to have some experience with a cling projects, which suggests that end result or short-term range of specification types (Figure 29). The length of the performance specifications are more appropriate types of warranty period ranges from 1 to 4 years. Shorter warranties contracting approaches. (3 years or less) require the full cost of the recycling to be bonded but are reduced to 50% for longer warranty periods. Materials testing, mixture testing, and specification par- Distresses specifically related to the surface treatment (e.g., ticulars were not well defined from the survey responses. HMA overlay) are excluded from the warranty. Performance Therefore, a combination of agency survey information, a measurements include fatigue cracking, edge cracking, rut- search for existing state specification in the National High- ting, and pothole formation. A closer examination of these way Specification website (FHWA 2010), and a literature nonstate agency warranty programs could provide key infor- search was used to help define typical characteristics of in- mation regarding performance history, performance criteria place recycling specifications. limits, warranty successes, and warranty administration. Key word searches of the National Highway Specifica- tion website were conducted for this information (Table 35). The key word search was conducted for "all agencies" and "all categories," which include standard specifications and supplements as well as innovations and emerging specifi- cations. The majority of the titles for each hit were evalu- ated for descriptions of in-place recycling methods of HMA. Unfortunately, a number of the search hits were related to a range of other topics (e.g., fly ash, slag, glass, and shin- gles). Cold planning was usually associated with milling for removal and use in central plant applications. TABLE 35 SPECIFICATION SEARCH PARAMETERS Key Word(s) No. of Hits FIGURE 29 Experience of agencies and contractors with Reclamation 56 different types of in-place recycling specifications. Percentages Pulverized 134 are based on the number of agencies and contractors with experience using the specific recycling process. Cold planning 445 Reconditioning 51 The agency and contractor responses were used to rank Reclaimed 228 and summarize the current use of different types of specifi- Reclaimed base 165 cations for in-place recycling projects (Table 34). Full depth recycling 228 TABLE 34 Recycling, recycled 343 TYPES OF SPECIFICATIONS USED FOR IN-PLACE RECYCLING CIR 133 Type of Specification HIR CIR FDR HIR 3 Method Often Often** Frequently Hot-in-place Crashed End Result Sometimes* Sometimes Frequently Cold-in-place 8 Performance Sometimes* Sometimes* Often* Warranty Sometimes* Sometimes Often* The specifications referring to in-place recycling of HMA Rarely = lower than 10% average of agency and contractor with experience. had little consistency in titles or terms (Table 36). The lack of Sometimes = between 10% and 25% average of agency and contractor with consistent terminology made key word searching difficult and experience. a simple summary impossible. Examples of the range of spec- Often = between 25% and 50% average of agency and contractor with experience. ifications found in the search are provided in Appendix B. Frequently = greater than 50% average of agency and contractor with experience. *Contractor response was significantly higher than agency with experience. Wisconsin Specification Section 325 is an example of the **Agency response was significantly higher than contractor with experience. simplest version of an FDR specification. The only specifics provided in this specification are requirements for a maxi- Method specifications are commonly used by agencies mum of 97% of the 50-mm (2-in.) RAP, timing of general for in-place recycling projects. However, agencies also rou- recycling activities, types of compactors for different lift tinely require the contractor to select additives and provide thicknesses, and a description of what is included in the pay- mix designs and make field adjustments for in-place recy- ment measurement (square yard).

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35 TABLE 36 IN-PLACE RECYCLING SPECIFICATIONS FOUND IN NATIONAL HIGHWAY SPECIFICATION WEBSITE State Section Title Special California CIR and full depth reclamation Provisions Connecticut 4.03 Cold reclaimed asphalt pavement Illinois Article 663 Asphalt pavements--hot-in-place recycling 2318 Cold-in-place asphalt pavement recycling Iowa 2125 Reclaiming present surfacing material (in-place or central plant) 2318 Cold-in-place asphalt pavement recycling Georgia 403 Hot-in-place recycled asphaltic concrete Kansas 605 Surface recycled asphalt construction Maine 307 Full depth reclamation Massachusetts 403 Reclaimed base course Mississippi 305 In grade modification JSP-04-12A One inch continuous process hot-in-place recycling with alternate methods of surfacing Missouri JSP-04-12B Two inch continuous process hot-in-place recycling with alternate methods of surfacing Montana 302 Bituminous pavement pulverization New Hampshire 306 Reclaimed stabilized base New York 402.6 Hot-in-place recycling of hot mix asphalt Oklahoma 311 Processing existing base and surface Pennsylvania 341 Cold recycled bituminous base course, cold-in-place Texas Item 358 Asphalt concrete surface rehabilitation Utah 02962 In-place cold recycled asphaltic base 310 Reclaimed stabilized base Vermont 409 Cold mixed recycled bituminous pavement Wisconsin 325 Pulverized and re-laid pavement OPSS 333 Construction specification for cold-in-place recycling Ontario, Canada OPSS 331 Construction specification for full depth reclamation OPSS 335 Construction specification for cold-in-place recycling with expanded asphalt Kansas and Georgia specifications had errors on state specification sites. A more complex specification is Maine Specification moisture content or dust control, paver (pick up, screed), 307 for FDR. This specification includes information on the construction timing and sequencing, weather conditions for size of the pulverized materials, new aggregate (as needed paving (no foggy, rainy conditions), curing (calcium chloride to meet gradation), equipment (pulverizer, grader, rollers, curing compound, until 1% moisture), testing (gradation, den- pulverizing), weather limitations, and testing for density sity, optimum moisture), payment measurement (square yard, control (nuclear gauge). square meter, tons of new materials, gallons of liquid stabiliz- ers), and what is included in the area measurement payment. Other specifications may or may not include specific direc- tions for surface preparation (sweeper or cutter to protect adja- There is no consistent use of in-place recycling terms cent surfaces), pulverizer features (self-propelled, automatic or specification content. It would be useful if there were depth control), mixer (self-propelled, automatic depth control, uniform guidelines for specification development and stan- liquid distributor, rotary pugmill), water truck for optimum dardization of terms.