Chemical-diffusive modeling of the self-healing behavior in concrete

In recent years, there has been an increasing trend in the study of self-healing materials with applications in different technological fields. These materials have the ability to retrieve their mechanical properties once the material is damaged. To model the behavior of this type of materials, new concept models have been developed based on extended mechanical variables that control simultaneously, both degradation and self-healing processes, i.e., damage and healing. In this paper, an uncoupled healing model for concrete, rationally based on physicochemical issues, is developed and numerically implemented. Although damage is a topic widely studied, healing, on the contrary, is a relatively novel concept for which not too much information is available both theoretically and experimentally in the branch of concrete mechanics. The model here proposed is available for concrete-based materials for which the healing mechanism is activated through precipitation of calcium carbonate inside the cracks, which covers a wide range of engineering applications. Two representative examples are implemented with the first mainly devoted to verification and parametric analysis while the seconds try to analyze a more realistic although still simplified application. Even though the model requires further validation, preliminary results show the influence on results of different model parameters as well as the qualitative trends available from experimental evidences shown in the literature.