Seismic Performance and Damage Mechanism of RC Double-Column Pier Structure with Triple Coupling Beams

Coupling beams are used in double-column high-pier bridges to improve the integrity of the two piers. The stiffness of coupling beams has a significant effect on the seismic performance of double-column piers. The seismic behavior of a double-column pier with triple-coupled beams was investigated by cyclic loading test. The failure mode and cyclic response, as well as the shear deformation of a double-column bridge pier, were analyzed to investigate its seismic behavior. The test results, especially after a drift ratio of 1/83, indicated the presence of non-uniform damage characteristics between the coupling beams. Finite element models were developed and parametric analysis was carried out after validation. The focus was on the effects of the variable stiffness of the coupling beam along its height. By analyzing the bearing capacity, ductility, and damage of the double-column piers, the upper flexible and lower rigid coupling beam is a more reasonable arrangement principle. The research results can provide a reference for the innovation design ideas of similar bridge piers.