钢框架在火灾作用下的结构失效过程分析  

Analyzing structure failure process of steel frames in fire

作　　者：鞠竹[1] 韩玉来[1] 董惠[1] 王振清[1] 

机构地区：[1]哈尔滨工程大学航天与建筑工程学院,黑龙江哈尔滨150001

出　　处：《华中科技大学学报（自然科学版）》2013年第7期21-26,共6页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(11272096);高等学校博士学科点专项科研基金资助项目(20112304110015);中央高校基本科研业务费专项资金资助项目(HEUCF20100201)

摘　　要：以二维钢框架为例,首先根据构件移除指标公式确定出结构中的关键构件,然后采用结构连续倒塌分析的改变路径法,通过时间历史分析函数将分析得到的关键构件从结构中移除.以需求能力比和转角作为失效准则,对剩余结构进行验算,分析构件移除对结构力学行为的影响.随后对剩余结构进行火灾次生灾害分析,研究火灾对结构产生的破坏作用.在给出构件失效后结构最大动力响应的同时,对剩余结构在火灾作用下的完整失效过程进行深入地研究,给出了一种受损伤结构的抗火分析方法.通过完整结构和受损伤结构受火行为的比较,得到不同结构火灾作用下的倒塌机理.A 2D steel frame was used for the numerical example.First,the critical element of the structure was determined according to the element removal index formula.Second,removal the critical element from the structure was simulated via a time history analysis function using alternate load path method.Taking demand to capacity ratio and chord angle for failure criteria,the influence of effectiveness of the element on structure mechanical behaviour was checked.Then,the remaining structure was exposed to fire secondly-disaster.Damage of the structure in fire was analyzed.Both the maximum dynamic response of the structure after the removal of the column,and the full failure process of the remaining structure under fire condition were provided.A fire resisting analysis method of structure with damage was given.The complete structure’s fire behaviour were compared with the damaged structure’s fire one,and the mechanism of the progressive collapse of the different structures was obtained.

关 键 词：钢框架 火灾 改变路径法 柱移除 失效过程 

分 类 号：TU391[建筑科学—结构工程]