Creep and drying shrinkage of concrete containing GGBFS

Abstract

Experiments were conducted on 150 × 600 mm cylindrical specimens to investigate creep and drying shrinkage of concrete containing ground granulated blast furnace slag (GGBFS). The creep strain was measured for 150 days under a constant sustained load. The creep strain recovery was measured for one subsequent month after the removal of the sustained load. The shrinkage strain was also measured for 180 days. The amount of cement replacement by GGBFS was 20%, 40% and 60% by weight of cement. The test results indicate that higher GGBFS percentage exhibits higher creep and shrinkage strains. At 150 days of sustained loading, the average creep coefficients of 20%, 40% and 60% GGBFS concrete are 16.3%, 33.3% and 55.2% higher than plain concrete. In the absence of a creep and shrinkage prediction model for GGBFS concrete, a modification factor is suggested for incorporating the effect of GGBFS proportion in the existing models. The available models for predicting creep and shrinkage strain of plain concrete are compared.