Discrete modeling of crack interaction and localization in concrete beams with multiple cracks

Abstract

This paper presents a numerical analysis of fracture modes in a plain concrete beam with multiple discrete cracks, focusing on crack interaction and localization. It contains three parts: justification of the strategy used to solve multiple-crack problems using a discrete approach, derivation of the coefficient of interaction, and numerical studies. The coefficient of interaction is defined based on the nodal force components at the tip of a crack, and its usefulness in analyzing various cracking behaviors is demonstrated through numerical studies. Under the given loading conditions, the cracking behavior of the plain concrete beam is shown to depend on the initial configuration of notches and their sizes. It is found that the intensity of crack interaction and its effect on crack localization can vary. As the crack localization progresses, the stress concentration at the dominant crack intensifies, and the crack interaction diminishes quickly.