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With the development of subway lines in urban areas, building structures are sometimes subjected to train-induced vibrations, and there is a need to develop prediction models to evaluate the vibration serviceability. In this paper, a new type of subway-depot system is investigated, where subway trains run through the top story of a 3-story metro depot, while the first two stories were developed for offices and shops to avoid the waste of large city areas. Considering the increasing use of such a structural system and the possible serviceability problems, the floor vibrations of a metro depot under moving subway trains were numerically simulated, where the train-track system was treated as the vibration source and studied separately, and the influence of train speed and fastener configuration on the vibration response was discussed. The metro depot was modeled taking the stiffness of the partition walls into account, and vibration responses of the building at different locations were compared and validated through field tests. Besides, vibration level of the second floor was evaluated using an acceleration index that considers frequency weighting. Finally, parameter analysis was carried out so as to provide some references to the vibration control.

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Under strong shocks, long-span spatial-latticed structures may collapse due to dynamic instability or strength failure. The elasto-plastic dynamic behaviors of three spatial-latticed structures, including two double-layer cylindrical shells and a spherical shell used for the 2008 Olympic Games in Beijing, were quantitatively examined under multi-support excitation (MSE) and uniform support excitation (USE). Numerical analyses described several important parameters such as the peak acceleration and displacement responses at key joints, the number and distribution of plastic elements, and the deformation of the shell at the moment of collapse. Results of the analysis revealed the features and the failure mechanism of the spatial-latticed structures under MSE and USE. In both scenarios, the double-layer reticulated shell collapsed in the "overflow" mode, collapse was governed by the number of invalid plastic elements rather than the total number of plastic elements, and the collapse of the structure began with damage to certain local regions near the supports. By comparing the numbers and distributions of the plastic members under MSE to those under USE, it was observed that the plastic members spread more sufficiently and the internal forces were more uniform under MSE, especially for lower apparent velocities in soils. Due to the effects of pseudo-static displacement, the stresses in members near supports under MSE were higher than those under USE. These regions are prone to failure during earthquakes and deserve special attention in the seismic design of reticulated structures. multiple support excitation (MSE), uniform support excitation (USE), elastic-plastic time history analysis, spatial-latticed structure, strength failure Citation:Ye J H, Zhang Z Q, Chu Y. Strength behavior and collapse of spatial-reticulated structures under multi-support excitation.