Effects of central column aspect ratio on seismic performances of subway station structures

Abstract

The subway station structures have a contradiction in its design of the cross section of the central columns: larger aspect ratio increases the longitudinal traffic capacity, yet decreases the lateral seismic capacity. However, both capacities are important. Thus, finding a reasonable aspect ratio has become a significant problem to be studied in depth. In this article, a series of time history analyses are carried out on a typical two-story three-span subway station structure, and ultimate bearing capacity analysis of isolated columns of various sizes is performed. The static axial compression ratio (ranging from 0.13 to 0.68) and the aspect ratio (ranging from 0.04 to 26.67) are taken as parameters, and their influence on internal force and damage to the structure are explored. It is found that the increase in axial compression ratio of the columns increases both the compression and tension damage and reduces the seismic performance of the station structure. However, the influence of increasing the aspect ratio of columns on the seismic performance of structures is more complicated. The compression and tension damage rises first (ranging from 0.04 to 1.67) and then decreases (greater than 6.67), while the tension damage of the structure increases monotonously. Finally, (0.15, 0.6) is given as the recommended aspect ratio range.