Analysis of the Collapse of Long-Span Reticulated Shell Structures Under Multi-Dimensional Seismic Excitations

The collapse processes of three typical long-span reticulated shell structures were simulated using nonlinear dynamic finite element analysis under strong seismic excitations. The plastic kinematic hardening model, which considers failure stain, was adopted for simulating steel. Both geometric and contact nonlinearities were considered in this study. The three failure states-i.e., dynamic local bucking, dynamic overall buckling, and whole collapse-were identified in accordance with the analysis results. Taking the Schwedler reticulated shell structure as an example, seismic waves were applied to the structure in three directions. The critical loads were obtained by the incremental dynamic analysis method (IDAM), and some critical state indices were obtained according to the dynamic responses. The results showed that all the critical indices need to be considered simultaneously in order to judge the dynamic collapse states.