2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Samir Chidiac, McMaster University
The need for sustainable concrete infrastructure is driving the development of smart structural materials. Inspired by the healing capabilities of living organisms, self-healing concrete utilizes a responsive healing system that closes cracks immediately when they form, effectively minimizing material deterioration, recovering durability and reducing the need for manual repair. One of the major categories of self-healing mechanisms is autonomous healing, which utilizes chemical, mineral, or bacterial healing agents that are not normally found in concrete. The healing agent is delivered via embedded vessels in the form of a continuous tubular network or as discrete microcapsules dispersed throughout the concrete. When concrete cracks, the vessel breaks and releases the reservoir of healing material into the crack, which effectively seals the crack and prevents further crack propagation. This study reviews the state-of-art pertaining to autonomous self-healing of concrete. This includes the material and manufacturing technologies and the efficiency of the self-healing systems. The healing effectiveness of the healing system is evaluated through the recovery of concrete mechanical properties and durability. The limitations and potentials of the proposed autonomous self-healing systems are discussed.