Analysis of crack spacing in reinforced concrete by a lattice model

Abstract

A new numerical method is proposed for prediction of crack spacing in reinforced concrete. It is assumed that the deformation pattern of crack spacing consumes the least energy among all kinematically admissible deformations, and the energy minimization approach is applied to predict crack spacing. To simplify the problem, a lattice model is used, in which the cracking process is represented by softening of the concrete bar elements. The crack spacing due to tension and bending is investigated. The results confirm that crack spacing can be predicted by energy minimization. To account for the influence of the bond slip between the concrete and the reinforcing steel, the traditional bond-link element is employed. The influence of the bond slip on the cracking pattern is studied through numerical examples. The results show that without considering bond-slip, the damage near the reinforcement is distributed rather than localized, whereas considering bond-slip, the damage near the reinforcement is localized. The influence of bond slip on crack spacing is significant.