不锈钢热轧槽钢压弯构件绕弱轴面内稳定性能研究  

In-plane global stability of hot-rolled stainless steel channel section beam-columns about minor axis

作　　者：冉红东[1,2] 简良雄 马云美[3] 孙瑶 RAN Hongdong;JIAN Liangxiong;MA Yunmei;SUN Yao(School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Key Lab of Structural Engineering and Earthquake Resistance,Ministry of Education(XAUAT),Xi’an 710055,China;China Northwest Architecture Design and Research Institute Co.,Ltd,Xi’an 710018,China;Department of Civil Engineering,Xi’an Jiaotong-Liverpool University,Suzhou 215123,China)

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]西安建筑科技大学结构工程与抗震教育部重点实验室,陕西西安710055 [3]中国建筑西北设计研究院有限公司,陕西西安710018 [4]西交利物浦大学土木工程系,江苏苏州215123

出　　处：《建筑结构学报》2023年第6期160-171,共12页Journal of Building Structures

基　　金：陕西省自然科学基金项目(2018JM5123)。

摘　　要：为研究S30408(EN1.4301)不锈钢热轧槽钢压弯构件绕弱轴的面内稳定性能,对18个中长柱进行偏心加载试验,分析其绕弱轴的失稳破坏模态和面内稳定承载力。试验前测量试件初始几何缺陷、荷载初偏心及截面残余应力分布。采用有限元软件ABAQUS建立不锈钢热轧槽钢压弯构件有限元模型,经与试验结果对比验证后开展参数分析,研究了初始几何缺陷及纵向残余应力对不锈钢热轧槽钢压弯构件绕弱轴面内稳定性能的影响。基于试验及有限元分析结果对现行规范CECS 410:2015《不锈钢结构技术规程》(简称规范)设计方法进行评估,并提出了改进设计建议。研究结果表明:中长柱的破坏模态均为绕弱轴整体弯曲失稳;按照规范计算得到的不锈钢热轧槽钢压弯构件绕弱轴面内稳定承载力较试验值总体偏于保守,对于试验及有限元分析结果与规范公式计算结果比值,正偏心工况下为1.31,负偏心工况下(弯矩作用使槽钢翼缘肢尖受拉)为1.21且部分试件偏于不安全;改进的设计方法能较合理地预测不锈钢热轧槽钢压弯构件绕弱轴的面内稳定承载力,对于试验及有限元结果与改进设计方法计算结果比值,正偏心工况下为1.07,负偏心工况下为1.05。To investigate the global stability and load-carrying capacities of hot-rolled S30408(EN1.4301)austenitic stainless steel channel section beam-columns about minor axis,18 beam-column specimens under combined compression and minor-axis bending were tested.The initial geometric imperfections,loading eccentricities and residual stresses of the beam-column specimens were measured prior to the member tests.The finite element(FE)software ABAQUS was used to develop FE models for hot-rolled stainless steel channel section beam-columns,and the numerical models were validated against the test results and then employed to perform parametric studies.The effects of initial geometric imperfections and residual stresses on the behavior of hot-rolled stainless steel channel section beam-columns were evaluated.The obtained test and FE results were then adopted to assess the accuracy of the relevant design rules stipulated in the current Chinese standard CECS 410:2015‘Technical specification for stainless steel structures’.Finally,an improved approach was proposed for the design of hot-rolled stainless steel channel section beam-columns under minor-axis combined loading.The results reveal that all the 18 tested beam-column specimens fail in a combination of minor-axis flexural buckling and in-plane bending,CECS 410:2015 results in overall conservative predictions of the load resistance,the ratio of the test and FE results to the code design rules is 1.31 in the positive loading eccentricity cases,and is 1.21 but with some unsafe predictions in the negative loading eccentricity cases(i.e.tensile bending stresses occur in flange tips).The proposed design approach is proved to be able to give accurate resistance predictions for hot-rolled stainless steel channel section beam-columns under minor-axis combined loading.The ratio of the test and FE results to the proposed design approach is 1.07 for the positive loading eccentricity cases,and is 1.05 for the negative loading eccentricity cases.

关 键 词：压弯构件 不锈钢 热轧槽钢 面内稳定 静力试验 稳定承载力 

分 类 号：TU391[建筑科学—结构工程] TU317.1