Abstract: The mechanism of surrounding buildings on the seismic response of subway stations was investigated based on the dynamic equilibrium characteristics of the building-soil-subway station model and a simplified method for the seismic design of subway stations considering the effects of surrounding buildings was proposed in this paper. A near-field model including a subway station and a surface building was established firstly. Comparing the dynamic characteristics of the near-field model to the model without surface building, we found that the seismic forces of surface building induced in an earthquake would be passed to subway station through the foundation and field. Since the main seismic forces of surface building were inertia forces which could be calculated using the response spectrum method, a simplified method was derived. Owing to acquiring the dynamic response of subway stations via static modeling and calculating, the method proposed herein consumes less analysis time and cost. Furthermore, a series of numerical simulation experiments was conducted to verify the simplified method and further evaluate its computational accuracy. The results of those tests revealed that: compared to the results of dynamic time history, errors in internal forces and deformations of the simplified method are less than 7% and 5%, respectively. Therefore, the simplified method has a high accuracy in engineering design.

Key words: subway station, dynamic interaction, seismic design, pseudo-static method