Mechanical characteristics of fiber-reinforced microcapsule self-healing cementitious composites by orthogonal tests

Abstract

This study combined the microcapsule self-healing system with fiber reinforced concrete (FRC), and investigated the effects of microcapsule content, mineral admixture type, mineral admixture content, and fiber type on tensile and compressive strength, ductility, and self-healing properties of the fiber-reinforced microcapsule self-healing cementitious composites by the orthogonal test method. For the uniaxial tensile and cubic compression tests, the optimum tensile strength group consists of a 2.2 mass ratio of GGBS, PE fiber, and no microcapsules. The optimum compressive strength group consists of a 2.2 mass ratio of GGBS, hybrid fiber, and no microcapsules. Microcapsule content and fiber type are the main factors affecting tensile properties, and an increase in the microcapsule content will reduce the tensile strength and compressive strength of the matrix. The optimum tensile strain group consists of 10% microcapsule content and a 2.2 mass ratio of GGBS and PE fiber. The results of the energy-based steady-state crack propagation test show that the fiber type is the most critical factor affecting the ductility, and the tensile ductility of the PE fiber group is higher than that of the PVA fiber group. The scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS) diagram proved the healing effect of the fiber-reinforced microcapsule self-healing cementitious composite.