Self-healing concrete with crystalline admixture made with different cement content

Abstract

Self-healing concrete (SHC) is obtained with self-healing agents, which can seal small cracks without additional repair works, improving concrete durability. The present paper studied the influence of cement content (450, 475, and 500 kg/m3) on mechanical properties (compressive and tensile strength) and porosity (capillary water absorption, water absorption, and void index) of SHC with crystalline admixture. A crack induction was carried out in SHC, and the results were compared with two reference concretes (with and without crack induction). SHC had similar compressive strength with reference concrete made without crack induction, independently of cement content. Water absorption and void index of SHC decreased with higher cement content, and a significant reduction of capillary water absorption was found after 90 days. The crystalline admixture was very efficient in decreasing concrete porosity mainly at longer ages. SHC made with high cement content developed a higher porosity reduction.