Current progress on biological self-healing concrete

This review outlines the specific methods and concepts of self-healing that have been adopted locally and globally. Based on the need for manual intervention, these methods and concepts of self-healing can be classified as passive or active. The theory of biological self-healing concrete is also analysed. The mechanism by which the diagenesis of biomaterials triggers and promotes self-healing in the tiny cracks of cement is explained. This paper introduces a biological multiple-triggered-switch scheme for the self-healing of cement-based cracks. The role of this mechanism in the continued and feasible self-healing of cracks is analysed.