Comparion of seismic response of single-layer reticulated dome under unform and incoherence three-directional excitations

Abstract

Seismic ground motions at structural supports are spatially varying and incoherent. The spatial incoherency effects should be considered for structures with large span and multiple supports. Two single-layer reticulated domes of 120m span, with and without substructures under incoherent multiple supports and uniform excitations were modeled and analysed in this study. Time-history responses of structures are obtained and compared for simulated ground motion records. For the simulation, use of existing phase difference spectrum models and coherence models were considered, and three-directional excitations (two horizontal directions and vertical direction) are considered. The analysis results show that the spatial coherency effect can influence the seismic responses of reticulated domes. The results also indicate that the seismic spatial coherency of all three directions can be important, especially for structures without flexible substructures.