Adding limestone fines as cement paste replacement to reduce shrinkage of concrete

摘要

To reduce the shrinkage of concrete so as to alleviate the various problems so caused, a common strategy is to decrease the cement paste volume. Herein, it is proposed to add limestone fines to fill into the voids between aggregate particles so that the cement paste volume can be decreased more substantially. Following a previous study on the effectiveness of adding limestone fines as cement paste replacement in reducing the heat generation of curing concrete, the aim of this study is to evaluate the effectiveness in reducing the shrinkage of hardened concrete. A number of concrete samples with limestone fines added to replace an equal volume of cement paste are tested and the results show that the addition of limestone fines as cement paste replacement could substantially decrease the ultimate shrinkage strain by as much as 28%, and significantly increase the compressive strength.