Modeling the uncoupled damage-healing behavior of self-healing cementitious material with phase-field method

Microbially induced calcium carbonate precipitation (MICCP), which is a biochemical process that utilizes microbial metabolic activities to precipitate calcium carbonate (CaCO3), can be used for damage-healing by crack filling. In this study, we develop a computational uncoupled damage-healing framework to predict the fracture-healing responses of a multifunctional vascular cementitious composite. The framework integrates a numerical model for self-healing cementitious materials into a damage model developed using the phase-field method. The numerical self-healing model is utilized to compute the MICCP healing based on the chemical and enzyme kinetics of microbial activities, whereas the phase-field method is employed to capture the fracture response of the material. This framework comprises three stages: Stage 1 - damage, Stage 2 - healing, and Stage 3 - re-damage of the healed structure. Using the load-displacement curve of the healed cementitious material, the proposed uncoupled damage-healing models can predict the recovery in material stiffness based on the MICCP healing ratio. The proposed framework can be applied to a wide range of fracture-healing problems in self-healing cementitious materials utilizing MICCP as the healing methodology.