宽厚比超限的高强钢方形截面轴心受压构件极限承载力*
- 摘 要
-
申红侠(西安建筑科技大学土木工程学院，结构工程与抗震教育部重点实验室，西安 710055)［摘要］采用有限元法分析了Q345，Q390及Q420钢宽厚比超限(b/t=40，50，60和70)的焊接方形截面轴心受压构件的极限承载力，并将计算结果和直接强度法、有效屈服强度法相比较。研究表明：有限元模拟结果和直接强度法计算结果吻合较好，有效屈服强度法略为保守；采用两种方法计算时，焊接方形截面应按a类而非《钢结构设计规范》（GB 50017—2003）规定的b类截面查稳定系数φ；采用有效屈服强度法时，板件正则化长细比应取λp=φfy/σcr,p。建议修订规范时将直接强度法和有效屈服强度法也纳入规范。［关键词］高强度钢； 焊接方形截面； 轴心受压构件； 局部整体相关屈曲； 极限承载力； 直接强度法； 有效屈服强度法中图分类号：TU391,TU3231,TU3112文献标识码：A文章编号：1002848X(2012)11011904Ultimate capacity of high-strength steel square box columns with large plate width-to-thickness ratioShen Hongxia(School of Civil Engineering, Key Laboratory of Structural and Aseismatic Engineering of the Education Ministry, Xi'an University of Architecture and Technology, Xi'an 710055, China)Abstract: The ultimate capacity of axially loaded welded square box section members made of high strength steel (Q345, Q390 and Q420), with width-to-thickness ratio of 40, 50, 60 and 70, was analyzed by finite element method. The numerical results were compared with the results calculated by direct strength and effective yield strength method. It shows that good agreements are observed between the results calculated by the finite element model and direct strength method, and the effective yield strength method is slightly conservative. A welded square box section with large width-to-thickness ratio should be classed with curve a instead of curve b as provided in Code for design of steel structures (GB 50017-2003) when using the two methods. The equivalent slenderness ratio λp of the plate should be taken as φfy/σcr,p, when the effective yield strength method is used. It is suggested that the direct strength and effective yield strength method should be added to the specification when modifying the national standard GB 50017-2003.Keywords: high-strength steel; welded square box section; axially loaded member; local-overall interaction buckling; ultimate capacity; direct strength method; effective yield strength method*陕西省教育厅专项科研计划项目（11JK0950），陕西省重点学科建设专项资金项目(E01001，E01003)。作者简介：申红侠，博士，副教授，Email: shenhongxia88@126.com。参考文献［1］ 石永久. 高强度和高性能钢材在建筑结构中的应用和发展［C］//第三届结构工程新进展国际论坛文集. 北京: 中国建筑工业出版社, 2009：397407.［2］ GB 50017—2003 钢结构设计规范［S］. 北京: 中国计划出版社, 2003.［3］ 施刚，王元清，石永久. 高强度钢材轴心受压构件的受力性能［J］. 建筑结构学报, 2009, 30(2): 9297.［4］ 施刚，石永久，王元清. 超高强度钢材焊接箱形轴心受压柱整体稳定的有限元分析［J］. 沈阳建筑大学学报：自然科学版, 2009, 25(2): 255261.［5］ GAO LEI, SUN HONGCAI, JIN FENGNIAN, et al. Loadingcarrying capacity of highstrength steel boxsections I: stub columns ［J］. Journal of Constructional Steel Research, 2009, 65(4): 918924.［6］ 王卫永,李国强,戴国欣.轴心受压高强度H 型钢柱抗火性能［J］. 重庆大学学报, 2010, 33(10): 7682.［7］ USAMI TSUTOMU, FUKUMOTO YUHSHI. Local and overall buckling of welded box columns ［J］. Journal of the Structural Division, 1982, 108(ST3):525542.［8］ USAMI TSUTOMU, FUKUMOTO YUHSHI. Welded box compression members ［J］. Journal of the Structural Engineering, 1984, 110(10):24572470.［9］ DEGE HERV, DETZEL ANNETTE, KUHLMANN ULRIKE. Interaction of global and local buckling in welded RHS compression members ［J］. Journal of Constructional Steel Research, 2008, 64(78): 755765.［10］ 陈绍蕃. 焊接薄壁箱形截面轴心压杆的承载力计算［J］. 建筑钢结构进展, 2009, 11(6): 17.［11］ 杨娜, 支旭东, 沈世钊. H型钢楔形薄壁构件的局部屈曲性能分析［J］. 土木工程学报, 2004, 37(8): 1115.［12］ 陈绍蕃. 钢结构［M］. 北京：中国建筑工业出版社, 1992.［13］ Supplement 2004 to the North American specifications for the design of coldformed steel structural members［S］. Washington,D.C. : American Iron and Steel Institute, 2004.
