火灾下双层柱面网壳结构连续倒塌分析  

Progressive collapse analysis of a double-layer lattice shell under fire

作　　者：尹越[1,2] 方喆立 刘红波[1,2] 陈志华[1,2] YIN Yue;FANG Zhe-li;LIU Hong-bo;CHEN Zhi-hua(College of Civil Engineering,Tianjin University,Tianjin 300072,China;Tianjin Key Laboratory of Civil Engineering Structures and New Materials,Tianjin 300072,China)

机构地区：[1]天津大学建筑工程学院,天津300072 [2]天津市土木工程结构及新材料重点实验室,天津300072

出　　处：《空间结构》2022年第1期13-20,63,共9页Spatial Structures

基　　金：国家自然科学基金项目(51678404)。

摘　　要：采用全过程动态拆除构件法进行火灾下某双层柱面网壳结构的连续倒塌分析,准确地模拟了火灾下网壳结构的连续倒塌行为及连续倒塌过程中构件拆除引起的结构动力响应.火灾下双层柱面网壳结构的关键构件为横向下弦杆及与之相连的受压腹杆,这些构件的失效沿纵、横两个方向的扩展将引起网壳的连续倒塌.连续倒塌过程中网壳结构动力响应的大小与失效构件拆除时长密切相关,瞬时拆除构件法高估结构的动力响应,加速结构的连续倒塌.在合理时长内拆除失效构件,才能准确地模拟网壳结构的连续倒塌过程.Progressive collapse analysis was conducted for a double-layer lattice shell under fire by removing failure members dynamically.The entire process of progressive collapse of the lattice shell and dynamic effect during the progressive collapse were successfully simulated.Lower-chord members along the span and the compressive web members connecting with them are the key members for the lattice shell under fire.The member failure propagates along transverse and longitudinal directions and results in the progressive collapse of the lattice shell.The dynamic effect during the progressive collapse is closely related to the speed of member removal.Instantaneous removing of failure members will overestimate the dynamic effect and accelerate the progressive collapse of the lattice shell.For accurate simulation of the progressive collapse of the lattice shell,failure member should be removed in a proper duration of time.

关 键 词：双层柱面网壳 火灾 连续倒塌 拆除构件法 动力效应 

分 类 号：TU393.3[建筑科学—结构工程]