In order to simulate the concrete structures degradation affected by corrosion phenomena, a development of a coupled mechanical and chemical damage model was carried out. The originality of this work is the using of finite volume method (fvm) and meshing with boundary layer approach to estimate the rate of corrosion propagation around rebar and correctly calculate damage parameter in each finite element. The effect of temperature on chemical diffusion is also modeled. In this study, a constitutive inelastic-damage model [1] is coupled with multi-species transport model (mstm) to describe concrete degradation due to water diffusion and chemical species transport in porous media as is concrete [2]. The constitutive inelastic-damage-mstm model is first validated by simulating a beam degradation with one reinforced rebar taken from literature, and after that the model is used to simulate the crack and damage of real-size underground structure. All numerical simulations were carried out using Linux-Parallel computing and an open-source code foam-extend.