Comparison of simplified seismic design methods for cross-section of underground structures of subway

Several simplified design methods for seismic design of cross-section of underground structures of subway have been proposed in the past decades, such as seismic coefficient method, free field deformation method, response displacement method and response acceleration method. These methods have been introduced into some seismic design codes in China, but there is lack of sufficient confirmation of their effectiveness and applicability. A comprehensive investigation of these simplified methods is made through a comparison of their assumptions, applicable conditions, parameters and others. Also their applicability is further explored by comparing them with dynamic response analysis of effective stress through simulation of underground structures of subway built in liquefiable soil deposits. It is shown that there still exists large discrepancies between the predicted capabilities of the two kinds of methods, and the applicability of the simplified methods is quite limited.