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22 Bid Letting AU, NZ, UK, SA 42 Project planning can provide critical input into the contract Canada 18 management aspects of highway maintenance. Typical proj- ect planning requires the letting of the chip seal project to fol- United States 17 low, proceed, or coincide with other road works (patching, crack sealing, line painting, etc.). Patching and crack sealing 0 10 20 30 40 50 should be completed as far in advance of the chip seal con- miles struction as possible to permit maximum curing time for those items (Wegman 1991). FIGURE 20 Typical length in miles of chip seal projects. The Washington State constructability study verified that patches and crack sealing are common causes of bleeding number of qualified chip seal contractors competing for their owing to localized increase of asphalt content over the sealed projects. The same phenomenon is found with state DOTs cracks and patches (Jackson et al. 1990). One study found that do not routinely use chip seals as part of their PM pro- that these activities should be completed a minimum of gram. The smaller dollar value of projects within these agen- 6 months before the chip seal to allow time for the patches to cies may isolate them from attracting qualified contractors. cure and evaporate most of the volatiles (Gransberg et al. 1998). Early preparation efforts can be realized only with RISK AND WARRANTIES effective coordination between the agency's maintenance operations and contracting group. Therefore, planning main- Contracts are the legal instruments used to distribute risk tenance activities should be performed with consideration of between the owner and the contractor in the construction the construction schedule. industry. The type of construction contract has a significant bearing on how the project's risk will ultimately be allocated. A contract management system with the ability to plan This extends beyond the risk differential between unit-price pavement preparation methods such as patching and crack and lump-sum contracts and into the amount of design that is sealing in the year before chip sealing would be ideal. Another completed by the chip seal contractor. Some of the survey best practice is for chip sealing projects to be contracted in respondents indicated that they buy chip sealing services as a way that will maximize curing time. Thus, practices such a commodity purchase rather than a construction project, and as letting the contract late in the chip seal season should be they allow the chip seal contractor to determine the exact avoided wherever possible. In line with the best practice of combination of materials and methods. Thus, the distribution maximizing curing time, contract management should restrict of chip seal project performance risk, along with those con- late mobilization of the project, and agencies should enforce tractual mechanisms to ensure that the contractor is held re- the contract's seasonal limitations in those cases in which the sponsible for that risk, has been explored. The relationships chip seal contractor has fallen behind schedule. between these mechanisms, specifically bonding and war- ranties, and their associated impact on chip seal performance Contractor Competition and Competence 100% The number of contractors bidding for an agency's contracts 100% 88% is an important determinant of both quality and price. Research 78% indicates that larger chip seal contracts produce a better 80% quality of chip seals, because the better qualified contractors appeared to be more attracted to larger contracts, both in terms 60% 55% 45% of quality control and fielding their best equipment and most experienced personnel (Gransberg at al. 1998). Survey respon- 40% 22% dents were asked to specify their typical project length. As 20% 13% shown in Figure 20, the typical overseas chip seal project is, to the extent possible, more than twice as long as its North 0% American counterparts. United Canada AU, NZ Counties States UK, SA and Cities Although typical chip seal project lengths were generally not provided from the counties and cities that responded to the survey, the trend was for counties and cities to express that Yes No their organizations encounter problems attracting a satisfac- tory number of bidders as shown in Figure 21, where 88% of FIGURE 21 Response to adequate number of experienced those respondents indicated that they did not have an adequate chip seal contractors.