Risk and Pay Factor Analysis of Washington State's Department of Transportation1994 Standard Specification

摘要

The original goal of this report was to determine risks assigned to thecontractors and WSDOT in their asphalt QA specifications, and examine the pay factors used by WSDOT in its sampling plan. By doing so the study provided insight into statistically based sampling plans including pitfalls that may be encountered. In recent years, there has been a trend toward statistically based contract specifications in an effort to continually improve product quality, and provide additional value for the cost. The AASHO Road Test of 1958-1961 produced a sufficient number of unbiased test results of construction materials and the techniques used to install them to show for the first time their variability and relationship to the specifications. The result of these findings clearly demonstrated that the significance of certain items in the specification simply was not known, nor were the real standard or level of quality the specifications were supposed to guarantee (TRB, 1976, p 3). This was the period in which the concept of performance based, or end-result specifications, was born and that a contract written with minimum standards would likely result in the same. The Blatnik Committee's discovery in 1962 that there was not 100 percent compliance with specifications almost lead to Congress passing a law making it a federal offense to knowingly incorporate nonspecification material in a highway project (TRB, 1976, p 3). (KAR) P. 669.