论文部分内容阅读
为研究铝合金板式节点刚度对单层球面网壳整体稳定性能的影响,制作一个跨度为8 m、矢高为0.5 m的K6型网壳模型,对网壳顶点施加4次单向循环荷载。试验结果表明,加载初期网壳表现出超刚性特征,即其刚度大于刚接节点网壳刚度;而后的节点螺栓滑移变形会降低网壳刚度,螺栓滑移引起的网壳变形很大且不可恢复。网壳的失稳属于整体跳跃失稳,但网壳屈曲后可继续承载,且荷载可进一步增大。最后一次单向循环加载时网壳因顶点杆件下翼缘的拉裂而破坏。另外,随着循环荷载逐级增大,网壳再加载初始刚度都有一定弱化。采用ANSYS有限元软件建立网壳分析模型,采用BEAM188单元和COMBINE 39单元模拟考虑节点半刚性的铝合金板式节点网壳杆件,节点弯矩-转角关系曲线采用四折线模型,有限元分析结果与试验结果吻合较好。
In order to study the influence of stiffness of aluminum alloy plate joints on the overall stability of single-layer spherical reticulated domes, a K6-type reticulated shell model with a span of 8 m and a sag of 0.5 m was fabricated. Unidirectional cyclic loading was applied to the top of the reticulated shell. The experimental results show that the initial reticulated shell exhibits ultra-rigid characteristics that its stiffness is greater than the stiffness of the reticulated shell, and the subsequent node slippage will reduce the rigidity of the reticulated shell. The deformation of the reticulated shell caused by bolt slippage may not be large restore. The instability of the reticulated shell belongs to the overall jumping instability, but the reticulated shell can continue to bear after buckling, and the load can be further increased. During the last one-way cyclic loading, the shell is destroyed due to the cracking of the flange under the rod. In addition, as the cyclic load increases step by step, the reticulate shell initial stiffness must be weakened. ANSYS finite element software was used to establish the shell model. BEAM188 element and COMBINE 39 element were used to simulate the semi-rigid aluminum alloy plate node grid shell member. The bending moment-corner curve of the node was modeled by the four-fold line. The results of finite element analysis The test results agree well.