腹板开矩形孔复杂卷边冷弯槽钢梁局部屈曲性能及直接强度法研究  

Local buckling behavior and direct strength method of cold-formed steel channel beams with web rectangular openings and complex edge stiffeners

作　　者：赵金友[1] 高攀 王钧[1] 孙阔 ZHAO Jinyou;GAO Pan;WANG Jun;SUN Kuo(School of Civil Engineering,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学土木工程学院,黑龙江哈尔滨150040

出　　处：《建筑结构学报》2020年第6期195-204,共10页Journal of Building Structures

基　　金：黑龙江省自然科学基金项目(LH2019E006);中央高校基本科研业务费专项(2572019CT01)。

摘　　要：为了研究腹板开孔复杂卷边冷弯槽钢梁的局部屈曲性能,以及探究北美冷弯型钢结构设计规范(AISI S100-2016)中腹板开孔冷弯槽钢梁局部屈曲直接强度法计算公式的可靠性,对孔高比(孔洞高度与腹板高度的比值)分别为0、0. 2、0. 4、0. 6和0. 8的10个腹板开矩形孔复杂卷边冷弯槽钢梁纯弯试件进行了静力试验研究。试验结果表明,开孔和不开孔试件均发生以局部屈曲为主的屈曲破坏模式,与不开孔试件相比,开孔试件的受弯承载力下降,且下降幅度随孔高比的增大而增大。利用ANSYS有限元程序对试验进行了模拟分析,分析结果与试验结果吻合良好;在此基础上,采用经试验验证的有限元模型,通过变换腹板高度、板厚和孔高比开展了有限元参数分析,并根据有限元参数分析结果对已有腹板开孔冷弯槽钢梁的弹性局部屈曲临界应力近似计算公式进行了修正。基于试验结果、有限元参数分析结果以及修正的弹性局部屈曲临界应力近似计算公式,对AISI S100-2016中开孔冷弯槽钢梁发生以局部屈曲为主破坏时的直接强度法计算公式进行了修正。In order to investigate the local buckling behavior of cold-formed steel channel beams with web openings and complex edge stiffeners and to assess the reliability of direct strength method for cold-formed steel channel beams with web holes controlled by local buckling stipulated in AISI S100-2016 ‘North American specification for design of coldformed steel structural members’,the static tests were carried out on ten pure bending cold-formed steel channel beams with rectangular web openings and complex edge stiffeners. The hole height-to-web depth ratios of those beams were 0,0. 2,0. 4,0. 6 and 0. 8,respectively. It is shown that the specimens with and without web openings fail with the buckling mode controlled by local buckling. The moment capacity of specimens with web openings is lower compared with specimens without web openings,and the moment capacity decreases with the increase of the hole height-to-web depth ratio. Tests were simulated by finite element program ANSYS. The simulation results show good agreement with the test results. Based on the above verified finite element models,the finite element parametric analyses were carried out by changing the web height,sheet thickness and the hole height-to-web depth ratio. The existed approximate prediction formulas of critical elastic local buckling stress were revised based on the finite element parametric analysis results. According to the experimental results,the finite element parametric analysis results and the revised approximate prediction method of critical elastic local buckling stress,the direct strength method formulas for beams with web openings controlled by local buckling in AISI S100-2016 ‘North American specification for design of cold-formed steel structural members’ were revised.

关 键 词：冷弯槽钢梁 复杂卷边 腹板开孔 静力试验 局部屈曲 弹性局部屈曲临界应力 直接强度法 

分 类 号：TU392.1[建筑科学—结构工程] TU317.1