组合节点刚度对组合框架的抗震性能影响分析

Analysis of Influence of Composite Joint Rigidity on Seismic Properties of the Steel-concrete Composite Frame

为研究钢-混凝土组合节点刚度对组合框架抗震性能的影响,首先讨论了组合节点的刚度及其影响因素,然后通过某多层钢结构工程实例,利用Ansys有限元软件建立了纯钢框架与组合框架,分别假定刚接及考虑节点刚度等共4种框架模型,进行了多遇地震反应谱分析及弹性时程分析,并进行了计算对比.计算结果表明,考虑钢框架的组合作用后,结构整体自振周期变短,基本自振周期降低了13.4%,说明结构整体刚度变大.但考虑节点刚度后,地震周期又有所加大,纯钢框架及组合框架基本自振周期均增大了17%,相应地震位移变大,2种模型的反应谱法分析顶层位移分别增大了8%,11%,说明组合节点刚度对结构的抗震性能是不可忽略的因素.

To study the main influence of composite joints rigidity on composite frame seismic properties, this paper at first discusses composite joint rigidity and influence factors, and then through a multi - storied steel project, creates frame composite frame and different joint style four model based with finite element software ANSYS, and contrasts the results of response spectrum analysis to elastic time - history analysis. The results which take the composite effect into account show that the natural vibration period is shorter by 13.4 %, the stiffness of the structure is larger than not. But considering the rigidity of joints, the natural vibration period is larger by 17%, the drifts of earthquake are larger, and the top drifts is larger 8 % and 11%. the rigidity of composite joints can not be ignored in earthquake.