A phase-field chemo-mechanical model for corrosion-induced cracking in reinforced concrete

We present a new mechanistic framework for corrosion-induced cracking in reinforced concrete that resolves the underlying chemo-mechanical processes. The framework combines, for the first time, (i) a model for reactive transport and precipitation of dissolved Fe2+ and Fe3+ ions in the concrete pore space, (ii) a precipitation eigenstrain model for the pressure caused by the accumulation of precipitates (rusts) under pore confinement conditions, (iii) a phase-field model calibrated for the quasi-brittle fracture behaviour of concrete, and (iv) a damage-dependent diffusivity tensor. Finite element model predictions show good agreement with experimental data from impressed current tests under natural-like corrosion current densities.