| This thesis presents the seismic response analysis of spatial lattice structures under multi-support and multi-dimensional earthquake inputs, which have different site type, seismic fortification intensity, boundary conditions and spans.First, the methods of multi-component seismic response analysis are summarized. Based on it, the pseudo excitation method presented by J. H. Lin is introduced to the seismic response analysis of space lattice structures. It is analyzed that how to use the multi-dimensional pseudo excitation method to sovle the random seismic response of space lattice structures under multi-support and multi-dimensional earthquake excitations. This method is proved to be an accurate solution of random vibration equation theoretically, in which all participant modes and the mode cross-correlation, and is effective in space structures with multiple-degree-of-freedom, close frequencies and long span.Secondly, these problems on the stochastic earthquake ground motion model and parameters, time delay of the motion, apparent velocity are studied. Based upon the code"Code for Seismic Design of Buildings"(GB50011-2001) and the demand of this thesis, self-power spectrum density, mutual-power spectrum density, coherence functions, and time delay of the motion suitable for the space lattice structures are proposed, the calculation parameters and the apparent velocity adapted to different site types are determined.Last, it is analyzed that the seismic response of space lattice structures with different site types, different seismic fortification intensities, different boundary conditions and different spans. A variety of lattice structures are chosen and studied, the spans of which are 40m, 60m, 80m, 100m and 120m. As one of the factors changes, the multi-component and multiple-support earthquake inputs would make different influence on the stress of the structures. And the variational laws of the stress are summarized.
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