Composite model for basic creep of high-strength concrete Available to Purchase

Most of the reported work on creep of high-strength concrete (HSC) covers measurements of total creep on standard specimens kept in a standard environment of 50% relative humidity and 23 °C. The results of these studies are used to establish the basic creep factor of high-strength concrete, assuming that the environmental effect on creep of HSC is similar to that for normal-strength concrete (NSC). However, some recent work has shown that the effect of the environment on creep of HSC is different from that observed for NSC, which indicates that a realistic creep model for HSC needs to be developed based on more fundamental material behaviour. This paper reports a theoretical study of a composite model for predicting basic creep of concrete, considering it as a composite material of coarse aggregate, fine aggregate and cement paste. The model is based on the age-adjusted effective modulus method proposed by Bazant, and can take into account the composition of the concrete, the degree of compaction and the hydration of cement paste. The model is shown to predict basic creep measurements reported in the literature with reasonable accuracy.