Book Description

Coarse aggregate is often one of the largest volume occupying components in a portland cement concrete system. With increases in transportation costs and depletion of many of the aggregate sources currently in use the need to reevaluate the performance of aggregates in concrete has arisen. Current aggregate testing requirements for many organizations have not been updated in decades, even with the advancements in aggregate testing equipment that are currently available. This research project investigates current used and potential test methods for evaluating coarse aggregate for use in portland cement concrete. Testing focused on determining the most appropriate aggregate property to evaluate and then determining the correlation to mechanical concrete properties. Relationships between potential aggregate tests and currently used aggregate tests were evaluated to determine if compatible relationships between methods were evident. For this purpose concrete mixtures were made at a fixed aggregate volume to establish if a link was evident between aggregate test properties and concrete. To establish a link between laboratory and real world performance field sites with known distress were visited to better establish limits for aggregate testing requirements. Results obtained provided the basis for recommendations for testing requirements and limits to be used for aggregates in portland cement concrete.