采用非线性纤维梁单元法的钢管混凝土组合框架动力响应分析

钢管混凝土结构已经广泛应用于我国高层和超高层建筑中,为研究该类结构的抗震性能,分别采用分离模量法和统一模量法对某13层钢管混凝土框架结构进行抗震性能分析,研究不同地震波作用下组合框架的模态和多遇地震下的弹性动力时程,对比组合框架顶点位移反应、加速度反应、层间侧移及动力放大系数等。研究结果表明,分离模量法和统一模量法建模方法在分析钢管混凝土框架抗震动力特性上总体相差不大,但前者可以考虑材料弹塑性,从而对结构弹塑性进行分析,而后者在弹塑性阶段需要用全曲线表达式,尚需进一步的研究。

Dynamic Response Analysis of Composite Frames with Concrete-filledSteel Tubular Columns Based on Non-linear Fiber Beam Element

Due to their excellent mechanical performance, such as seismic performance and fire resistance performance, concrete-filled steel tube structures have been widely used in high and super-high building structures. In order to investigate the seismic performance of concrete-filled steel tube structures under the effect of earthquake, this paper developed a finite element model of composite frames with concrete-filled steel tubular columns and steel beams with RC slabs by the separate modulus approach and uniform modulus approach, respectively. By using the ABAQUS software, the two validated calculation models of the separate modulus approach and uniform modulus approach were used in order to perform finite element analysis and elastic dynamic time-history analysis of a 13-story composite frame structure with concrete-filled steel tubular columns and steel beams with RC slabs under three different frequent earthquake waves. The top story displacement versus time curves, acceleration time-history responses, story lateral displacement, and the dynamic magnification factors of the frame, were contrasted based on the two models. The results show that the separate modulus approach and uniform modulus approach did not vary much for the dynamic performance analysis of composite frame with concrete-filled steel tubular columns and steel beams with RC slabs under frequent earthquake. However, the separate modulus approach can be used in elastic-plastic analysis, while the uniform modulus approach needs the expression of the stress-strain curve in elastic-plastic analysis, which requires further study.