Fatigue analysis of rc slabs reinforced with plain bars based on the bridging stress degradation concept

Abstract

There is an increasing demand from researchers and engineers to know the fatigue behaviors of RC bridge slabs under a moving load. Therefore, many numerical and experimental studies have been conducted to predict the fatigue life of these slabs. Most of these studies focused on the modeling of fatigue behaviors of RC slabs reinforced with deformed bars. However, many RC slabs in use today are reinforced with plain bars, and they are suffering from fatigue damages. A numerical method based on the bridging stress degradation concept is presented in this study to simulate the fatigue behaviors of RC slabs reinforced with plain bars under a moving load. The bond-slip effect between a reinforcing bar and its surrounding concrete is taken into consideration by adding equivalent bond strain to plain bar strain. The numerical model is verified using previous experimental data. This model is also able to capture the cracking pattern, change in displacement and rebar strain. The numerical results provide a good agreement with the experimental ones.