为探究半刚性节点单层球面网壳在地震荷载作用下的动力响应特征,针对沈北新区80 m球径螺栓球节点单层球面网壳,采用有限元软件ANSYS,引入节点试验和数值分析数据来模拟实际工程中螺栓球节点的抗弯性能,建立可考虑节点刚度的精细化数值模型,并进一步考虑局部杆件和节点加强、壳体外表面安装围护材料等不同结构条件的变化,在此基础上,对其开展了自振特性及在不同峰值地震荷载作用下动力响应分析.分析结果表明:本项目已建成的大跨度螺栓球节点单层网壳具有良好的抗震性能,但螺栓球节点单层网壳局部开洞会形成明显的刚度薄弱区,建议洞口周边采用焊接球节点并对周圈杆件加强.若在现有结构外表面安装围护玻璃则导致结构的抗震性能明显降低,罕遇地震下,节点最大位移将比竣工结构增大140.1%,杆件最大应力增大77.8%,节点最大位移时程曲线有发散迹象,表明结构有发生整体倒塌的可能性.
Taking an 80-meter-span singer-layer reticulated dome which has been constructed in the Shenbei New District as an example, the natural frequency characteristics and dynamic response of the singer-layer reticulated dome under different peak seismic loads were analyzed with the FE software ANSYS.Based on the data of the numerical analysis and the test of the joints, the bending performance of bolt-ball joints were obtained and introduced into the seismic response analysis considering the joint stiffness.Different structural models were established to investigate the effect of the structure model changes, including strengthening the local members and joints and installing maintenance materials on the surface of the structure.The results show that the constructed 80-meter-span singer-layer reticulated dome has a good seismic performance, but the local hole on the structure is the obvious weak area.It is suggested that the welded ball joints should be used around the hole, and the members around the hole should be strengthened.The seismic performance of the structure will be reduced by installing maintenance materials on the surface, and the maximum displacement of the reticulated dome increases by 140.1%, and the maximum internal force increases by 77.8% under the rare earthquake action.A divergence trend of the curve can be found in the time-displacement curve of the structure, showing the possibility of a whole collapse of the structure.