The maximum crack width is frequently used as a damage indicator for reinforced concrete (RC) structures. However, predicting crack width and crack spacing through conventional nonlinear finite element (FE) analysis with the smeared crack concept is difficult. Accordingly, a crack propagation index based on FE analysis is proposed. The maximum crack width observed from past experiments on RC shear walls and the increment of element volume in the FE analysis were associated to derive the method for calculating the index. The index simulated the increasing trend of maximum crack width observed in the past experiments.
