Shrinkage of high-strength calcium sulfoaluminate cement concrete with impact of pre-soaked lightweight aggregate internal curing

Abstract

The effect of internal curing using pre-soaked lightweight aggregate in high-strength calcium sulfoaluminate cement concrete on shrinkage and internal humidity was investigated. Five mixture proportions with induced internal curing water (absorbed by lightweight aggregate) to cement (w IC /c) ratios of 0, 0·03, 0·06, 0·09 and 0·12 were used in the experiments. The experimental results show that the decrease of internal humidity is gradually reduced with an increase in w IC /c ratio. Accordingly, both autogenous and drying shrinkage of concrete also gradually decrease with an increase in w IC /c. Internal curing cannot eliminate the autogenous shrinkage completely because part of the autogenous shrinkage develops within the humidity-saturated stage for early-age concrete.