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31 Caltrans has an on-going program called "Just In Time" However, this study found that 21 of 28 U.S. DOTs and 7 of (JIT) training that it associates with a number of construc- 8 Canadian MOTs require the microsurfacing contractor to tion means and methods. It requires existing certifications for develop the job mix formula. As discussed in chapter three, selected construction processes as part of its general specifi- this also involves characterizing the existing substrate. There- cations. The following example for concrete could be applied fore, the risk of warranting another's design disappears, and to microsurfacing as a programmatic system to enhance both the risk associated with the existing conditions can be miti- contractor and agency personnel qualifications. gated by merely examining the project site and deciding whether microsurfacing is an appropriate treatment. If it is Mandatory training is part of the Caltrans specification. Caltrans not, the contractor makes a "no-bid" decision. Thus, because requires Just-In-Time Training for the rapid-setting concrete pave- the classic level of uncertainty is reduced, a microsurfacing ment projects. Contractors and engineering personnel directly project shows the potential to be a better candidate for a war- involved with these projects are required to attend. Once the train- ing is completed, a one-year certificate is given to each participant ranty provision than other pavement preservation and main- (Feldman and Feldman 2007). tenance treatments. The responses to the three questions discussed previously Critical Warranty Details coincide with the Pavement Preservation Expert Task Group initiative to develop a certification program at the national The survey asked each respondent to indicate whether or not level found in the literature (FHWA 2010a) and allows one to they used warranties in their program and, if they did, to dis- conclude that a microsurfacing training and/or certification close the details of that warranty. Table 23 contains a summary program is needed. Once implemented, certification would of those responses, as well as each agency's rating of their benefit the construction community by giving certified con- microsurfacing performance. The results can be broken into tractors a competitive advantage. Requiring DOT personnel two groups. The first are agencies that require a standard con- to be certified would not only enhance agency quality control/ struction warranty of materials and workmanship (usually for quality assurance (QC/QA) programs but also provide a com- 12 months) on all their contracts and the second are those that mon base of knowledge from which quality issues could be have written separate microsurfacing warranty provisions. discussed between the contractor and the agency inspector. Table 24 is an example of the supplementary specification that the Ohio DOT (2008) uses for its microsurfacing projects. WARRANTIES A copy of this specification is contained in Appendix C to fur- nish all the details for the interested reader. Looking at the Pavement warranties are controversial for at least two reasons. table, one can see that 8 in 28 U.S. and 7 of 8 Canadian agen- First, they are often proposed for projects where the contractor cies couple microsurfacing with warranties. Table 24 shows furnishing the warranty did not construct the pavement struc- measurable threshold criteria developed by the agency to permit ture upon which the new pavement or surface treatment is con- an objective evaluation of microsurfacing performance dur- structed (Ohio DOT 2007). Second, the contractor normally ing the period of the warranty. Finally, because microsurfac- has no input to the structural design process and therefore is ing is most often used to extend the underlying pavement's asked to guarantee the risk that the design was adequate with- life, the warranty creates a mechanism to ensure that purpose out any control over the magnitude of that risk (Austroads is accomplished. Therefore, it appears that warranting micro- 2003a). Figure 12 illustrates the continuum of microsurfacing surfacing projects for which the contractor has furnished the contract risk and relates the four categories to the type of con- job mix formula is not problematic to the same degree as other tract risk that is inherent to each point on the continuum. Note types of road construction. that the three examples that are shown in the figure are not the only possibilities that can be observed. However, they do rep- Because warranties are often used to create an incentive for resent the majority of this study's findings in both the literature quality work (Thompson et al. 2002), comparing the agency's and the content analysis. microsurfacing performance evaluation is instructive. Table 23 shows that 3 of the 4 "fair" ratings came from agencies with Owner agencies that require construction warranties may warranties. Therefore, the question of whether the warranty expect to pay a premium for that privilege (Ohio DOT 2007). is an attempt to enhance the quality of the agencies' micro- Input Driven Output Driven Performance Driven Owner Designed Owner or Contractor Designed Contractor Designed Prescriptive Specification Prescriptive Specification Performance Specification Owners Constr uction Methods Contractor's Construction Method Contractor's Construction Method Construction Unwarrantable Construction Warrantable Long-Term Warranties FIGURE 12 Contract risk continuum (Scott et al. 2006).

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32 TABLE 23 SUMMARY OF WARRANTIES REPORTED IN THE SURVEY Microsurfacing Agency Warranty Performance Rating (state or province) Length Nature of Microsurfacing Warranty from Survey Indiana 3 years Friction, raveling, rutting Fair Louisiana 1 year Materials and workmanship Good New Hampshire 1 year Surface defects Excellent Nevada 2 years Standard construction warranty Good New York 1 year Delamination, snowplow damage, flushing, and Good raveling > 2.0 SY Ohio 2 years See Table 24 for details Good Oklahoma 1 year Standard construction warranty Fair Texas 2 years Rutting, flushing, and raveling Fair Alberta 1 year Adhesion (raveling) Good British Columbia 1 year Standard construction warranty Good Manitoba 2 years Performance specification includes warranty provision Excellent Nova Scotia 2 years Standard construction warranty Good Ontario 2 years Flushing, raveling Good Quebec 1 year Standard construction warranty Good Saskatchewan 1 year Standard construction warranty Good surfacing program or if the increased performance monitoring had unit prices that were only 0.18% more than those without demanded by a warranted pavement surface has made the (Ohio DOT 2007). The same report contained information on agency more aware of the defects that form in newly applied the perceptions of the change in microsurfacing quality by Ohio microsurfacing. The Ohio DOT's guidance for selecting micro- DOT personnel, which showed that 69% believed the impact to surfacing projects on which a warranty can be required high- be an improvement. Contractors were also surveyed as to what lights the need to carefully evaluate the pavement's existing changed from their perspective and it showed that the top three condition before adding a warranty. contractor-perceived warranty-induced improvements were: This Item [warranty specification] can be used on minor reha- 1. Quality conscious construction bilitation projects which do not require a structural overlay . . . 2. Better workmanship Projects which do not qualify for preventive maintenance nor have 3. More design input (Ohio DOT 2007). been designed in accordance with the minor rehabilitation require- ments are not eligible for a warranty. High stress locations are not candidates for micro-surfacing . . . With warranty, however, it is This connects with the notion introduced at the beginning more important that proper pavements be selected and the existing of this section regarding risk exposure. The risk allocation pavement is properly prepared, otherwise the warranty could be changes when the contractor is allowed to have input to the voided (Ohio DOT 2008). design and that unit prices in Ohio did not skyrocket when warranties were introduced confirms the assertion that micro- Warranty Cost Experience surfacing projects are good candidates for warranties because the contractor has more control over the design and construc- In 2007, the Ohio DOT published a cost analysis study of its tion process. This confirms the Ohio DOT warranty guidance warranty program that disproved that notion. It found over a directing engineers to carefully select "proper pavements" for three-year period that microsurfacing projects with a warranty warranted microsurfacing projects. TABLE 24 SUMMARY OF OHIO DOT MICROSURFACING WARRANTY SPECIFICATION Distress Threshold Level Type (per 500 SF of surface area) Description Bleeding/ 300 SF (28 SM) Excess asphalt binder that creates a shiny, reflective condition that Flushing becomes tacky to the touch at higher temperatures. Surface Loss 120 SF (11 SM) Loss of surface interlock by traffic wear, debonding, or delamination. Raveling 300 SF (28 SM) "Moderate" level raveling as defined in the Strategic Highway Research Program (SHRP) "Distress Identification Manual for the Long-Term Pavement Performance Project" (SHRP-P-338). Rutting 0.25 in. (6.5 mm) continuous Measure the wheel path with a 4 ft (1.2 m) straight edge. in any segment Only applies during the first 120 days after the Form C-85 is issued. Maintenance 2 years 75% of the amount bid for the microsurfacing pay item. Bond Source: Ohio DOT (2008).