The Strategic Highway Research Program (SHRP) has completed a program of research dealing with highway concrete that has produced new tools for designing portland cement concrete mixes, placement temperature advice, and procedures for diagnosing problems with concrete field performance. Significant advances in concrete technology produced by the research are new and improved methods of identifying concrete aggregates that react detrimentally with high alkali cement and those which are subject to damage by freezing and thawing. In addition to rapid and positive screening tests for aggregates, procedures for designing mixes that are safe from alkali-silica reactivity (ASR) and resistant to damage by freezing and thawing were developed in the durability investigations. An expert system for concrete durability has been developed that will assist highway engineers in making decisions related to the diagnosis, material selection, and repair on rehabilitation of concrete pavements and structures. The research has also produced new guidelines for high performance concretes and their uses in highway applications. Several innovative nondestructive test procedures were developed to help the highway engineer obtain quality control information during construction.
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