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For a multi-story underground structure, distribution and amplitude of seismic earth pressure along its side wall depth during an earthquake are critical for seismic design and safety evaluation. In this paper, a series of 1-g shaking table tests were conducted on a four-story subway station firstly. Experimental results showed that the distribution of maximum lateral dynamic earth pressure appeared an “S” shape, which was distinguished from that of a single-story underground structure. In the latter case, it is generally in a form of a triangle distribution. Furthermore, parametric study was carried out through nonlinear dynamic time history analyses using the general purpose finite element code ABAQUS. Attention was paid on influences of types of soils, structural stiffness, and vertical earthquake component on the distribution of seismic earth pressure. Numerical results showed that structures surrounded by sand suffered larger dynamic earth pressure than that those surrounded by clay. Peak dynamic earth pressure of a flexible structure was a little smaller than that of a rigid one. And vertical earthquake component excited lateral dynamic earth pressure in some degree.

Seismic earth pressure, Multi-story underground structure, Shaking table test, Parametric study, Stiffness