Numerical simulation of cracking in reinforced concrete members by an embedded model

Abstract

Purpose -The purpose of this paper is to describe the development of an embedded crack finite element (FE) model for reinforced concrete (RC) structures, including a bond-slip methodology to take into consideration the steel contribution in the rupture process, capable of capturing the global behavior of the structure as well as details of cracking phenomenon. Design/methodology/approach -The reinforcement contribution is added in the equilibrium at element level in an embedded crack FE model, based on displacement localization lines inside the elements. Findings -The model is able to determine the steel stress in the crack besides the volumetric average steel stress. It is shown that the steel stress in the crack can be considerable greater than the average value. Other important aspect detected is the contribution of the concrete softening in the steel stress in the crack and in the overall behavior. The number, the distribution and the opening of cracks can be estimated too. Practical implications -The yield of the steel in the cracking process can be detected more precisely by this methodology, allowing a better design and understanding of RC structures. In addition, the knowledge of crack openings is an important information to predict corrosion and other degradation phenomena of the reinforcement bars. Originality/value -The bond-slip procedure is linked with the embedded crack model in an original way: sliding gives the crack width. Moreover, the inclusion of steel forces in the crack equilibrium balance was not a usual procedure and permits an understanding of reinforcement effect in both levels (macro and micro) studied in this work.