Simulation of chloride ion transport in concrete under the coupled effects of a bending load and drying-wetting cycles

摘要

The transport of chloride ions in concrete under the coupled effects of a bending load and drying-wetting cycles accelerates the degradation of marine concrete. Based on the microstructure characteristics of concrete, the models of the tortuosity of concrete under a bending load were built. Considering the interaction between the transport of water and the tortuosity in the concrete microstructure, a nonlinear diffusion-convection model of the water and chloride ions transport in unsaturated conditions were also proposed in this paper. Finally, a two-dimensional variable coefficient model of chloride ion transport in concrete under the coupled effects of a bending load and drying-wetting cycles was also established based on Fick's second law, which was numerically solved using the alternating direction implicit (ADI) method. The results show that the values predicted agree with those of experiments and those reported in the literatures. (C) 2020 Elsevier Ltd. All rights reserved.