ABSTRACT
In this paper, cold reinforcement method of bonding steel angles is developed to reinforce the distortion-induced fatigue cracks in steel bridges. Numerical simulation is employed on full-scale steel girder models to study the effectiveness of cold reinforcement methods. The dimensions of initial crack considered in the finite element model came from full-scale I-shaped steel girder tests for distortion-induced fatigue mechanism tests of horizontal gusset plate web gaps. The results demonstrate that the stiffness of web gap region increases, and the out-of-plane deformation, the stress and stress intensity factor at the crack tip decrease dramatically after reinforcement. The parametric studies show that the reinforcement method became more effective in reducing the out-of-plane deformation and stress demand as the stiffness of the elements increased, with the lowest stress occurring when the steel angle reached the optimal size. And bonding steel angles connecting the vertical stiffener and the horizontal gusset plate is more effective than bonding steel angles connecting the vertical stiffener and web. Adhesive reinforcement technique dose not introduce secondary stress into the fatigue sensitive details. Moreover, the process of the reinforcement has no negative influence on the fatigue sensitive details of web gaps.
