Numerical simulation of bond degradation subjected to corrosion-induced crack by simplified rebar and interface model using RBSM

The bond degradation subjected to corrosion-induced crack was investigated numerically using 3D Rigid Body Spring Model (RBSM) in which rebar was modeled by solid elements without modeling explicitly the details of rebar ribs. The proposed numerical model considers both corrosion expansion and shear stress transfer behavior through the interface elements. Validation of proposed model showed that it is possible to obtain reasonable bond performance of non-corroded specimen as meso-scale models. By comparison with experimental results, the proposed model was verified to reproduce the bond deterioration considering corrosion-induced crack with different concrete cover thickness. Moreover, bond deterioration mechanism subjected to corrosion-induced crack was clarified through the crack development and stress distribution of concrete and was found to be the combined effects of degradation of the compressive stress in diagonal compression struts and ring-tension around rebar. Bond deterioration of specimen with larger concrete cover is more sensitive to formation of corrosion crack.