Response analysis of high-speed railway isolation bridge under near-fault earthquake: refined modeling method of co-simulation and full-bridge shaking table test

In order to explore the response law of typical high-speed railway isolation bridges under near-fault earthquakes, this paper proposes the OpenSees-MATLAB co-simulation modeling method based on Client-Server technology for analysis, and carries out a large-scale full-bridge shaking table test. The co-simulation method provides a new idea for the refined modeling of high-speed railway isolation bridges, which can help researchers introduce the developed refined mechanical model into the bridge system. In this paper, the feasibility and accuracy of the co-simulation calculation are verified by comparing the numerical calculation results with the shaking table test results, and the seismic response law of the high-speed railway isolation bridge is analyzed based on the shaking table test and numerical calculation. The results show that the vertical ground motion component (VH) has a significant and random effect on the seismic response of different components of the high-speed railway isolation bridge with hyperboloid friction pendulum bearing and viscous damper. Based on the probability statistics method, this paper proposes a response error upper bound ($R{E}_{upper}$) value with a confidence level of 95 % to quantify the influence of VH. The logarithmic regression model proposed in this paper can quickly and accurately predict the $R{E}_{upper}$ of the high-speed railway isolation bridge caused by the VH, which can help to correct the seismic response without considering the VH.