Spatial Effect Analysis on Shaking Table Tests of Subway Station Structure In Liquefiable Ground

摘要

Based on the test data of shaking table tests of subway station structure in liquefiable ground under both near-field and far-field earthquakes, the spatial effects of dynamic pore water pressure (PWP)and peak ground acceleration (PGA)of liquefiable ground as well as peak strain response of the subway station structure are analyzed. The results show that there exists time-lag phenomenon of dynamic PWP ratio of each measuring point on different observation planes. The characteristic of input ground motion has a noticeable influence on the spatial effect of dynamic PWP ratio. The PWP ratio obtained on the major observation plane presents to be larger than that on the minor one when under far-field Songpan wave. Meanwhile, the peak acceleration of measuring points on both major and minor planes increase with the growing peak acceleration of earthquake. The law of PGA and frequency spectral character of measuring points on different observation planes or at different depth varies with each other, and there present remarkable spatial effect. The peak strain of central cylinders at the top and middle floors on the major plane appear larger than that on the minor planes. However, the peak strain of central cylinders at the bottom floor are more remarkable than that of the top and middle floors, There are sharp contrasts among the peak strain responses in different spatial positions of the station structure.