Numerical simulation of Cl^- diffusion in concrete

Reinforced concrete structures being in the marine environment for a long time, the chloride ion in the sea water is injected into the concrete, and cause the corrosion of steel bars, which shortens the service life of reinforced concrete structures. This paper reports a hydration model based on self-organized growth to simulate the microstructure of concrete. The lattice Boltzmann method is used to simulate the diffusion of chloride ions with and without electrokinetic Effect in concrete microstructure generated by our model. The simulation results show that the Effective diffusivities of the chloride ions reduce as the water-cement ratio decreases and the hydration degree increases. For the pores size similar to the electric double layer thickness, the electrokinetic Effect is not ingored and negative charged surface can hinder the chloride ions intruding into the pore. This paper is helpful for marine concrete structures' protection and enhances durability of structures.