Improved Specifications for Hydraulic Cement Concrete

摘要

This report reviews the general problems associated with the application of statistical techniques to hydraulic cement concrete, and discusses the potential advantages and disadvantages to applying such techniques to concrete used in the construction of transportation facilities. For the Virginia Department of Highways and Transportation, contracts for concrete structures generally involve small volumes of concrete, and the usual frequency of sampling and testing does not provide sufficient test results for establishing specifications based on usually recommended risks to both the contractor and the state. Increases in the frequency of testing to provide the recommended risks would result in excessive increases in costs. Also included is a resume of practices and requirements in states other than Virginia using statistical concepts in their specifications for hydraulic cement concrete.