Self-Healing Concrete: A Review of Recent Research Developments and Existing Research Gaps

Abstract

Self-healing materials are defined as the materials that are able to partially or completely restore their original functionality after they have been damaged. In cementitious materials, such as concrete, this concept is referred to the capability of material to seal the cracks without any manual interventions after damage, accompanied by regaining of the mechanical properties, which results in a more durable and sustainable structure. In addition to the available literature which fully describes different methods of applying self-healing into cement-based materials and evaluates their efficiency, new approaches and novel techniques have been proposed for this purpose. This paper presents a brief review of both autogenous and autonomous mechanisms of self-healing, with an emphasize on the recent research advancements. Since the major concern regarding the application of autonomous self-healing in concrete structures is the additional cost caused by the healing agents, the improvement of autogenous self-healing which is an inherent performance of cementitious materials by providing a favorable condition for the process (e.g. high-performance fiber reinforced cementitious composites) may pave the way towards construction industry. However, there are still a few aspects of self-healing concrete missing in the literature that inhibits this technology from being utilized in the construction. Therefore, a comprehensive section is proposed in this paper discussing the major gaps and outlooks in the field of self-healing concrete.