甘肃省体育馆钢桁架防连续倒塌分析与机理研究

Anti-progressive collapse analysis and mechanism study on steel truss of Gansu Province Gymnasium

以甘肃省体育馆钢桁架为研究对象,根据事件控制、概念设计和直接设计法对由平面桁架构成的主桁架体系及悬挂结构体系进行防连续倒塌方法探讨。结合设计依据对荷载组合、失效准则进行了讨论。根据完整结构与剩余结构应变能不同的思想,提出了基于位移向量改进的构件重要性分析方法。并对主桁架系统及悬挂结构的重要构件、几何位置分布、整体结构中空间作用的分布情况进行了分析。按构件重要性评定方法所得结果与工程经验及数值分析结果一致,能定量地判定整体结构中的关键构件,为拆除杆件法提供了必要的判定依据,便于工程实践。采用ABAQUS数值分析平台进行了结构连续性倒塌动力响应分析,并对内力重分布机制进行了研究,结果表明结构具有较强的抗连续倒塌能力。

Taking the steel trusses of Gansu Province Gymnasium as the research object,the method of preventing progressive collapse of the main truss system and suspension structure system composed of plane truss was discussed based on event control,conceptual design and direct design methods. Based on the design basis,the load combination and failure criteria were discussed. Based on the idea that the strain energy of the complete structure is different from the strain energy of the residual structure,an improved component importance analysis method based on improved displacement vector was proposed. The main components,the distribution of geometrical positions,and the distribution of spatial effects in the overall structure of the main truss system and the suspension structure were analyzed. The result of evaluation method of component importance was consistent with the result of engineering experience and numerical analysis results. It could quantitatively determine the key components in the overall structure,and provide the necessary basis for determining the rod-dismantling method,which was convenient for engineering practice. The ABAQUS numerical analysis platform was used to analyze the dynamic response of structural progressive collapse,and the internal force redistribution mechanism was studied. The results show that the structure has strong resistance to progressive collapse.