薄柔H形截面双向压弯钢构件极限承载力研究  

STUDY ON ULTIMATE BEARING CAPACITY OF BIAXIAL COMPRESSION-BENDING STEEL MEMBERS WITH THIN AND SLENDER H-SHAPED SECTION

作　　者：杜辉波 程欣[1] 张超 陈以一 DU Hui-bo;CHENG Xin;ZHANG Chao;CHEN Yi-yi(College of Civil Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;College of Engineering,Shanghai Sanda University,Shanghai 201209,China)

机构地区：[1]太原理工大学土木工程学院,山西太原030024 [2]上海杉达学院工程学院,上海201209

出　　处：《工程力学》2022年第9期191-203,共13页Engineering Mechanics

基　　金：国家自然科学基金面上项目(51978437)。

摘　　要：为探究薄柔H形截面双向压弯构件的极限状态性能,采用ABAQUS建立了不同轴压比、腹板和翼缘宽厚比的H形截面构件在不同加载角度下的参数分析模型,分析中考虑了材料非线性、几何非线性及残余应力的影响,并基于已有试验数据验证了该模型的适用性。基于经典弹塑性稳定理论,提出了用于确定双向压弯构件极限状态的判定准则,对于塑性铰截面定义为截面出现塑性铰时达到其极限状态;对于由局部屈曲控制的薄柔截面其极限状态为屈曲起始时刻,且该准则能够准确识别出板件局部屈曲的发生。通过最小二乘法拟合得到双轴弯矩极限相关曲线,呈现出腹板和翼缘宽厚比及轴压力的复杂相关影响关系。提出了考虑材料的强化作用和板件相关作用的极限相关计算公式,能够良好地预测H形截面双向压弯构件的极限承载力,且不受截面分类的限制,具有良好的适用性。To investigate the ultimate behavior of H-section members with large width-thickness ratios under a combined biaxial compression-bending,the parametric analysis models of H-section members with different axial force ratios,web and flange width-thickness ratios and different loading angles were developed by ABAQUS.Material and geometric nonlinearity were considered throughout the whole analysis,and the finite element models were validated by previous laboratory test results.Based on the elastic-plastic stability theory,a criterion for determining the ultimate state of biaxial compression-bending members was proposed.For plastic-hinge sections,the ultimate state is defined as the occurrence of plastic hinge.For slender sections controlled by local buckling,the ultimate state is the initial buckling moment,with the occurrence of plate local buckling been accurately identified through the criterion.The ultimate interactive curves of biaxial bending moments were obtained by least-square method,within which complicated interactive effects of width-thickness ratios of web and flange and the axial force were noted.The ultimate interactive formula for biaxial moments considering the strain hardening effect of material and the correlation effect of plate was proposed.Not limited by section classification,the proposed method is proved to have good applicability and accuracy.

关 键 词：极限状态判定准则 H形截面 双向压弯 局部屈曲 极限相关曲线 

分 类 号：TU391[建筑科学—结构工程]