Simplified Seismic Analysis Of Integrated Station-Bridge Structure

Integrated Station-Bridge Structure is the developing type of the new structures in recent years. The earthquake mechanism, failure mode, seismic design and the reserch of it is still at an early stage at present.In our country we still lack the seismic design code of the rail transportation about this hub station, The seismic behavior and the design method has to be studied. The capacity spectrum method based on the pushover analysis is commonly used in seismic performance evaluation.How to consider the soil-structure interaction and how to select the model of the lateral force loading to finish the pushover analysis of such large-scale structure are rarely reported.Based on the establishment of the complex Integrated Station-Bridge model and verified the validity of the simplified model. The improvement method of the SRSS load patten of later force for this simplified model and compared with other lateral force loadings with the capacity spectra graph have been proposed in this paper.To reduce seismic demand spectrum the kinematic effects and foundation damping effects from the SSI effect have been considered and improved in the process of analysis.Combine the spectrum curve and the demand spectrum curve in the same coordinate system to evaluate the structure's seismic performance in the earthquake.Compared with the dynamic characteristic of the seismic response analysis to solve the practical engineering problems.In this paper,the research work are as follows:1. Considering the truss effect, a simplified model(SM) was constructed based on Sap2000 and Midas/Gen software, respectively.Explain the rationality and effectiveness of the simplified model in seismic performance.2. Applying some type of lateral loading,pushover analysis was performed. The plastic yielding mechanism of the structure was analyzed.Compared with the dynamic response,the SRSS lateral loading modes was validated.3. Based on the recent theory of the soil-structure interaction, I designed raft foundation and pile foundation in the simplified model,using the nonlinear seismic response method in FEMA440.The results show that the raft foundation is favorable than the pile foundation in the earthquake performance.4. Using the dynamic time history analysis method in the simplified model, this paper choose eight ground motion records and focus on the effects of EL Centro wave and CHICHI wave.The results show that the dynamic time history response analysis of the records is consistent with the pushover analysis on the average displacement.Maximum base shear has no comparable.To analyze the structural damage should consider the flexible foundation.