Mesoscopic simulation of steel corrosion process in concrete and its damage to concrete cover

In atmospheric or chlorine environment, the corrosion process of steel rebars embedded in concrete can be initiated by concrete carbonation process or chloride penetration process, respectively. Along with the steel corrosion process, tensile stress will occur in concrete around the steel rebars, and cracks will be formed when the stress reaches the tensile strength of concrete. This paper mainly studies the uniform and nonuniform corrosion processes of steel rebars by lattice model at meso-scale. First of all, the ideal models of uniform and nonuniform steel corrosion processes are development. Secondly, an integrated procedure based on lattice model is proposed to identify the crack pattern in concrete. Thirdly, some typical examples, including corrosion process of a single steel rebar and multi steel rebars, steel corrosion process in angular region, nonuniform steel corrosion process, etc., are simulated. Finally, the damage of steel corrosion process to the concrete cover is studied based on the indexes of damaged area ratio and maximum crack width. The results show that the lattice model at meso-scale can produce a more realistic crack pattern in concrete, and the non-uniform steel corrosion process can result in a severer damage to the concrete cover than the uniform steel corrosion process.