Fracture Mechanics–Based Fatigue Life Prediction Method for RC Slabs in Punching Shear Failure Mode

Abstract

In the last few decades, a punching shear failure model has been commonly observed in reinforced concrete (RC) bridge deck slabs around the world, which makes studies on the fatigue performance of RC bridge slabs an urgency. This paper focuses on the critical punching shear cracks, and the analytical fatigue life prediction method developed for RC bridge deck slabs that fail in a punching shear mode under moving wheel loads. In the proposed method, the fatigue crack growth is assumed to be as a result of concrete bridging stress degradation and rebar-concrete interface bond-slip degradation. With the obtained crack growths of the punching shear cracks, the fatigue life is predicted following a certain punching shear failure criterion combined with experimental observations. The reliability of this method is then confirmed with a positive outcome between predictions from the proposed method and results from experiments as well as some empirical equations from statistically fitting experimental results.