POLYURETHANE CEMENT REINFORCEMENT FOR SEISMIC TESTING OF CURVED BEAM BRIDGES PIERS

The "bending and torsion coupling" effect of curved bridges increases the likelihood of shear fracture and bending collapse of curved girder bridge piers and columns under earthquake action, leading to serious consequences such as overall collapse or overturning of the bridge structure. Polyurethane cement is commonly used as a reinforcement material for structural seismic reinforcement due to its excellent performance. In this study, a three-way shaking table test was conducted on a curved girder bridge, and an OpenSees finite element software was utilized to establish a fiber unit model of the abutment specimen. The model was then used to conduct parameter sensitivity analysis in order to investigate the influence of abutment height and polyurethane reinforcement on the seismic performance of polyurethane cement-reinforced abutment specimens. The results indicate that higher abutments lead to decreased reinforcing effects of polyurethane cement, while greater thicknesses of polyurethane cement result in improved reinforcing performance. Specifically, it was found that higher abutments diminish the reinforcing effect of polyurethane cement, whereas thicker layers of polyurethane cement reinforcement yield more pronounced effects. Based on data from parameter sensitivity analysis, parameters were optimized and the most economical parameters were derived. These findings provide a sufficient theoretical basis for utilizing polyurethane cement for reinforced curved beam bridge piers.