Interfacial stress of carbon fiber patch bonded to transverse cracked steel plate reinforcement

A three-dimensional elastic-plastic finite element model was established in finite element software ANSYS to investigate the interfacial stress of carbon fiber patch bonded to transverse cracked steel plate reinforcement. The patch and adhesive were modeled as linear elastic. The steel plate was modeled as elastic-plastic. The load-deflection curve of the steel was obtained by bending test. The influence of crack depth, adhesive thickness, patch thickness and patch length on reinforcing efficiency was studied. The results show that the peel stress of the adhesive was distributed symmetrically along the center line, mainly concentrated on the crack center, near the crack and the patch ends. The peel stress at the crack center was always greater than the near crack. The shear stress is anti-symmetric along the center line, and the shear stress at the crack center is zero, mainly concentrated near the crack and plate end. The debonding may be initiated from the vicinity of the crack. Increasing the crack depth can significantly increase the peel stress and shear stress at the crack, but has little effect on the stresses at the end. Increasing the thickness of the adhesive can reduce the peel stress and shear stress at the crack center and near the crack, and the shear stress at the ends, but has little effect on the peel stress at the ends. Increasing the patch thickness can reduce the stress at the crack but increase the stress at the end. Increasing the patch length cannot reduce the stress at the crack, but significantly reduce the stress at the end.