Aggregate-Based Modulus of Elasticity for Florida Concrete

摘要

The current empirical model for the Florida Department of Transportation (FDOT) concrete modulus of elasticity (E) is a function of concrete compressive strength and unit weight. Recent testing shows that this model consistently underestimates E for FDOT concrete. This underestimation may lead to construction problems caused by the overprediction of camber and the deflection of concrete structural members. £ values for the typical concrete mix used in FDOT projects were experimentally determined at various concrete ages. Regression analyses were used to find the £ models that best fit the generated data, and such models were compared with existing E models from the literature. It was found that the aggregate type and specific gravity play significant roles in influencing the E value of concrete. The best-fit £ models for FDOT concrete, together with suggested modification factors for various aggregate types, are recommended.