高强钢焊接薄腹矩形管截面压弯构件平面内的极限承载力  

In-plane ultimate carrying capacity of high-strength steel welded thin-webbed rectangular tube section beam-columns

作　　者：申红侠[1] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055

出　　处：《西安建筑科技大学学报（自然科学版）》2015年第5期642-648,共7页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金："十二五"科技支撑计划课题(2013BAJ10B03-0)

摘　　要：本文采用ANSYS有限元软件建立模型分析了高强钢(名义屈服强度为460 MPa)腹板高厚比超限的焊接矩形管截面偏压构件的极限承载力,以及构件长细比、腹板高厚比、翼缘宽厚比和相对偏心率对极限承载力的影响,提出腹板高厚比超限高强钢压弯构件平面内极限承载力计算公式.研究表明:考虑初弯曲和残余应力影响的双重非线性有限元模型能够很好地模拟高强钢焊接箱形截面偏心受压构件的局部-整体相关屈曲;高强钢薄腹矩形管截面压弯构件平面内无量纲化极限承载力Pu/(Afy)与构件长细比、腹板高厚比和翼缘宽厚比近似为线性关系;高强钢薄腹矩形管截面偏压构件的轴力和弯矩相关曲线近似为直线;按边缘纤维屈服准则推导的公式经过修正之后可用于计算高强钢压弯构件局部-整体相关屈曲的极限承载力.The ultimate load-carrying capacity of eccentrically loaded welded rectangular tube section members made from high strength steel with a nominal yield stress of 460 MPa was analyzed by ANSYS finite element program. The influences of the slenderness ratio, web depth-to-thickness ratio, flange width-to-thickness ratio, and relative eccentricity ratio on the ultimate bearing capacity were investigated. The calculation formulas for predicting the in-plane ultimate carrying capacity of high strength steel beam-columns with large depth-to-thickness ratios were proposed. The study shows that the double nonlinear finite element model with the geometric imperfections and residual stresses taking into account can simulate the local-overall interaction buckling behaviors of the eccentrically loaded welded box-section compression members. The nondimensional in-plane ultimate bearing capacity Pu/（Afy） is approximately linear with the increase of the slenderness, depth-to-thickness and width-to-thickness ratio, respectively. The correlation curves between the axial force and flexural moment of the high-strength steel thin-webbed rectangular tube section beam-columns are nearly linear. The formula deduced from the yielding criterion of the cross-sectional edge stresses after having been modified can be used to predict the local-overall interactive buckling strength of high strength steel beam-columns.

关 键 词：高强度钢 焊接矩形管截面 偏压构件 局部-整体相关屈曲 极限承载力 有限元法 

分 类 号：TU391[建筑科学—结构工程] TU323.1