考虑畸变屈曲的冷弯薄壁型钢卷边槽形截面构件设计可靠度分析  

Design Reliability Analysis of Cold-Formed Thin-Walled Steel Members with Lipped Channel Sections Considering Distortional Buckling

作　　者：姚行友 李元齐[3] 

机构地区：[1]南昌工程学院江西省水利土木工程基础设施安全重点实验室,南昌330099 [2]南昌工程学院江西省水利土木特种加固与安全监控工程研究中心,南昌330099 [3]同济大学土木工程学院,上海200092

出　　处：《建筑钢结构进展》2017年第6期65-74,共10页Progress in Steel Building Structures

基　　金：国家自然科学基金(51308277;51078288);江西省科技厅自然科学基金(20151BAB206055)

摘　　要：基于已有的冷弯薄壁型钢卷边槽形截面构件承载力试验研究结果,对不同牌号冷弯薄壁型钢卷边槽形截面构件考虑畸变屈曲的有效宽度法承载力计算模式不定性进行了分析,并统计了冷弯薄壁型钢强度不定性和几何特性不定性。在此基础上,采用改进一次二阶矩方法,按《冷弯型钢结构技术规范》(修订稿)的抗力分项系数要求,计算了不同牌号冷弯薄壁型钢卷边槽形截面受压构件在不同可能荷载组合下的可靠指标。结果表明:对于LG550、S350、S280冷弯薄壁型钢卷边槽形截面受压构件,按《冷弯型钢结构技术规范》(修订稿)的抗力分项系数计算得到的可靠指标均能满足目标可靠指标的要求,证明了所采用的考虑畸变屈曲的有效宽度法计算构件承载力的适用性。Based on the experimental study results of cold-formed thin-walled steel lipped channel sections,the uncertainty of strength capacity calculating method using the effective width method considering distortional buckling for different material types of cold-formed steel compressed members is researched.The uncertainty of material strength and geometric characteristics of the typical sections are statistically analyzed.According to the recommended resistance partial coefficient in the draft of‘Technical code of cold-formed steel structures＇（GB 50018）,the reliability indexes of cold-formed thin-walled steel lipped channel sections under compression is investigated using the improved first-order second-moment method considering different possible external loading combinations.The analyzed results show that using the recommended resistance partial coefficient in the code draft,the reliability indexes of the compressed members can meet the target reliability index well.The suitability of the corresponding calculating modes of strengthcapacity considering distortional buckling is established.

关 键 词：冷弯薄壁型钢 卷边槽形截面 畸变屈曲 有效宽度法 改进一次二阶矩方法 可靠指标 

分 类 号：TU392.1[建筑科学—结构工程]