Abstract: The equivalent response acceleration method for transverse seismic analysis of underground structures is systematically studied in this paper. Firstly, results of the dynamic time history analysis method are set as the benchmark to evaluate the adaptability of the equivalent response acceleration method through numerical examples. Then, error sources of the equivalent response acceleration method are dissected and overcome. An improved equivalent response acceleration method is proposed by introducing the dynamic response adjustment coefficient β. Finally, the applicability of the proposed method is evaluated through numerical examples. Results show that, the results of internal forces and deformations obtained from the equivalent response acceleration method are all smaller than those from dynamic time history analysis method. Moreover, its accuracy can be improved with the increase of soil shear velocity but less affected by the buried depth. Further research finds that the error of the equivalent response acceleration method comes from the fact that, the interference effect of the underground structure on the dynamic response of the surrounding soil is ignored in the method. After improvement and optimization, the improved equivalent response acceleration method is proposed to further consider the interference effect. Compared to the traditional equivalent response acceleration method, the proposed method has a wider applicability and better calculation accuracy, which provides a novel approach for seismic design and analysis of underground structures.

Key words: underground structures, seismic design, dynamic time-history analysis method, equivalent response acceleration method, improved equivalent response acceleration method