Abstract
Laboratory experiments were conducted to investigate the effects of locally available natural lightweight aggregates (LWA's) on volume changes and mechanical properties of high-performance concrete (HPC). The normal aggregates fraction of high-performance concrete was replaced with fine and coarse LWA's at three different replacement levels, 5%, 10% and 20% by volume. The test results indicated a significant reduction in the autogenous shrinkage of high-performance concrete at 56 days without a corresponding considerable reduction in compressive strength of the same concretes. The test results have also shown that up to 20% volume fraction of coarse LWA's could be used for mitigating the volume changes of HPC with a slight reduction in compressive and splitting tensile strengths, and elastic modulus. Therefore, this investigation recommends the use of locally available natural LWA's as a viable curing technique for minimizing the volume changes and risk of cracking of HPC's without compromising their mechanical properties.