基于楼板双向受拉模型的钢框架结构连续倒塌分析

组合楼板作为钢框架结构的主要构件,对结构的抗连续倒塌能力产生较大影响,但现有的结构抗连续倒塌研究大多没有考虑楼板的影响。基于组合楼板的双向受拉模型,分析组合楼板在钢框架结构连续倒塌过程中的受力,提出考虑楼板拉结力作用的失效点竖向承载力简便计算方法。基于简化模型,通过有限元分析软件进行框架连续倒塌分析,验证计算方法的准确性,探讨楼板对塑性铰机制、极限承载力、失效点动态反应的振幅和周期的影响。研究表明,楼板能有效地提高结构抗连续倒塌性能。

PROGRESSIVE COLLAPSE ANALYSIS OF STEEL FRAME STRUCTURE WITH COMPOSITE FLOOR SLAB TWO-WAY TENSION MODEL

Composite floor slab,as one of major steel frame structural elements,could greatly influence the antiprogressive collapse performance of structures.But the influence of slabs was not taken into consideration in the existing researches.In this paper,based on the two-way tension model of composite floor slab,the mechanical behavior of composite floor slabs in the process of progressive collapse was analyzed,and established a simple calculation method of ultimate bearing capacity at failure point considering the tie force of slabs.Progressive collapse analysis of frames based on the simplification model is simulated by the finite element method,in order to validate the simple calculation method,and investigate the slab's influences on plastic hinges,ultimate bearing capacity,amplitudes and periods of dynamic response at failure point,the result shows that slabs can effectively enhance the performance of structure to prevent progressive collapse.