Modeling of damage-healing and nonlinear self-healing concrete behavior: Application to coupled and uncoupled self-healing mechanisms

Self-healing materials have recently become more popular due to their capability to autonomously and autogenously repair the damage in concrete material. A simple damage healing law is proposed in this paper. The proposed damage healing law is based on a time-dependent healing variable which represents the opposite of the damage variable. The damage-healing model is applied on an isotropic concrete material at the macroscale under tensile load. The coupled and un-coupled self-healing mechanisms are studied using the proposed model and new healing variables are defined for each self-healing mechanism. Both healing mechanisms represent the capability of the material to autonomously and autogenously heal the cracks in concrete material. In addition, the so-called nonlinear healing theory is applied on both coupled and uncoupled self-healing mechanisms, and compared to the classical self-healing theory. The objective of the present work is to describe the capability of the proposed damage-healing model to describe the behavior of the partially and fully healed concrete material after it has been damaged in both coupled and uncoupled self-healing mechanisms using both linear and nonlinear self-helaing theories. The results show that the damage-healing model is capable to simulate both coupled and uncoupled healing mechanisms, and the nonlinear healing theory underestimates the healing efficiency in both coupled and uncoupled healing mechanisms comparing to the classical healing theory.