面向连续倒塌的RC框架结构柱拆除优先级研究

Study on Priority of Column Removal for Progressive Collapse of Reinforced Concrete Frame Structures

以外荷载做功为倒塌程度评价指标,分别采用线性静力分析、非线性静力分析研究了钢筋混凝土框架结构柱拆除优先级。采用拆除构件法对不同层、跨数的RC框架结构开展线性静力分析,总结拆柱优先级及规律,再通过非线性静力方法分析结构抗倒塌能力并验证拆柱优先级。结果表明:线性分析得到的拆柱优先级与非线性分析的优先级具有良好一致性;8层4跨结构拆单柱的最优方案为底层中柱,拆双柱的最优方案为底层边跨两柱。

The external load work was employed as an index for assessing collapse degree of reinforced concrete(RC)frame structures.Using the alternative path method,both linear and nonlinear static analysis were conducted to investigate the priority of columns removal.Initially,linear static analysis was carried out on RC frame structures with different floor and span numbers,and the priority and laws of columns removal were summarized.Subsequently,nonlinear static method was used to analyze the anti-collapse capacity of the structure and verify the columns removal priority.The results show that columns removal priorities obtained from linear and nonlinear analysis are in good agreement.For an eight-story,fourspan structure,the optimal schemes for removing single/double columns are the middle column and the two columns of the side span at the bottom floor,respectively.