Abstract:Procedures for artificial simulation of multi-point seismic acceleration histories with consideration of spatially non-uniform seismic ground motion are demonstrated to provide reasonable ground motion input for the numerical models. By establishing three-dimensional numerical model of underground rock cavern groups,seismic responses of the underground cavern groups under spatially uniform and non-uniform ground motion are carried out. It is shown that:(1) seismic response of the cavern groups is very similar to the time-history curves of displacement of the exciting sources,which indicates that the inertial effect of the rock mass can be ignored;and (2) seismic response mainly depends on the amplitude of the seismic waves;the spatial non-uniform effect has no negative impact on the underground cavern groups under the axial length ranging from 300 m to 400 m. Spatially non-uniform seismic ground motion,therefore,cannot be taken into account in the seismic safety assessment of the similar underground rock cavern groups.