考虑下部支承效应的单层柱面网壳结构抗震性能研究

为研究下部支承对单层柱面网壳整体结构抗震性能的影响，建立了包含下部支承的整体结构有限元模型。通过增量动力分析方法对典型算例开展参数分析，分析了下部支承刚度、屋面荷载等参数对整体结构抗震性能的影响规律。结果表明：考虑下部支承与单层柱面网壳的耦合效应后，结构的自振频率减小，整体结构的刚度明显减弱；单层柱面网壳耦合体系的强震失效模式为强支承结构的网壳动力强度破坏与弱支承结构的支承动力强度破坏；随着支承刚度的增加，整体结构的承载力先减小后增大，网壳结构的塑性发展程度先增加后减小，下部支承结构的塑性发展程度逐渐减小；支承刚度越大，屋面荷载对结构承载力的影响越明显，整体结构的承载力随着屋面荷载的增加逐渐降低；考虑下部支承后整体结构的承载力降低了42.4%~85.5%，降低的原因主要包括下部支承结构的动力放大作用和柱间的不同步效应。

Seismic performance of single-layer cylindrical latticed shell considering effect of lower supporting structure

In order to investigate the influence of the lower supporting structure on the seismic performance of the single-layer cylindrical shell structure, a finite element model was established. Based on the incremental dynamic analysis, the parametric analysis were carried out to investigate the influence rules of supporting stiffness, roof load and other parameters on seismic performance of the whole structure. The results show that natural frequency and stiffness of the whole structure decrease obviously after considering the coupling effect of lower support and single-layer cylindrical latticed shell. Under strong earthquake, the failure pattern is the dynamic strength failure of the reticulated shell for the coupling structure with strong support. On the other hand, the dynamic strength failure of the support is identified for the coupling structure with weak support. With the increase of the support stiffness, the bearing capacity of the whole structure and the plastic deformation of the reticulated shell decrease first and then increase, and the plastic development degree of the lower support structure gradually decreases. The greater the support stiffness, the more obvious the influence of roof load on the structural ultimate bearing capacity. The ultimate bearing capacity of the whole structure decreases with the increase of roof load. The ultimate bearing capacity of the whole structure decreases by 42.4%-85.5% after considering the lower support, which may attribute to the dynamic amplification of the supporting structure and the asynchronous effect among columns.