Early Age Strength Healing Effect of Cementitious Composite Incorporated Self-Healing Microcapsule

Abstract

Received 27 February 2019; accepted 02 September 2019

This paper aims to explore early age strength healing effect of cementitious composite incorporated self-healing microcapsule and curing activity of self-healing microcapsule. Particle characteristic of the microcapsule and micromorphology of cement paste incorporated the microcapsule were characterized by SEM. Curing activity of the microcapsule was analyzed by macroscopic solidification test, DSC and TGA. The influence factors of early age strength healing ratio in cementitious composite incorporated self-healing microcapsule were studied. The results showed that epoxy resin microcapsule had favorable micromorphology. Epoxy resin microcapsule core material had good curing activity and possessed the ability to play the healing role in cementitious composite. Healing temperature and healing age had less impact on the healing effect of the microcapsule in cementitious composite. The microcapsule could be kept good shape in cement paste and combined with cement paste closely. The microcapsule also could rupture and had better dispersion in cement paste. The main fracture behavior of the microcapsule was based on small hole ruptured when cement paste did not occur macro damage. When pre-loading was 0.75 σ_max, the particle size of microcapsules was range from 75 μm to 150 μm, proportion of epoxy curing agent was 20 % and proportion of the microcapsule was 6 %, early age strength healing ratio reached the highest of 24.1 %.