- 摘 要
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(浙江大学建筑工程学院, 杭州 310058)
[摘要]关于风吸力作用下C形和Z形简支檩条稳定承载力的计算,欧洲规范(Eurocode 3)和我国《门式刚架轻型房屋钢结构技术规程》(CECS 102∶2002)都取其受压下翼缘作为弹性地基上的压杆来求解临界荷载。然而,该方法的计算值与已有试验值相比过于保守。由檩条绕固定轴扭转屈曲的总势能可求得风吸力作用下C形和Z形檩条的弹性临界弯矩,计算其正则化长细比,然后采用修正的欧洲钢结构协会(ECCS)钢梁整体屈曲的稳定系数公式,计算檩条的弹塑性稳定系数,从而求得檩条的稳定承载力。对比结果表明,此方法的计算值与试验值更吻合。
[关键词]风吸力; 檩条; 临界荷载
中图分类号:TU392.5 文献标识码:A 文章编号:1002-848X(2015)06-0080-06
Capacity of purlins for torsional buckling about fixed axis under wind uplift
load and comparison with tests
Feng Yixiao, Tong Genshu, Zhang Lei
(School of Architecture and Civil Engineering, Zhejiang University, Hangzhou 310058, China)
Abstract:To calculate critical loads of Cshaped and Zshaped purlins under wind uplift load, their lower flanges are simplified as struts on elastic foundation in both Eurocode 3 and Technical specification for steed structure of lightweight building with gabled frames(CECS 102∶2002). But this method is proved to be overconservative compared with test results in previous studies. The elastic critical moments of Cshaped and Zshaped purlins under wind uplift load, derived from total potential energy of torsional instability about fixed axis, were used to compute the normalized slenderness. The elastic\|plastic stability factor of the purlin was determined by using a modified European Convention for Constructional Steelwork (ECCS) formula of global buckling stability factor of steel beam, thus critical loads of purlins can be obtained. The predicted results are compared well with available test results, showing a better agreement.
Keywords:wind uplift load; purlin; critical load
*国家自然科学基金项目(51478421)。
作者简介:冯一笑,博士研究生,Email:fengyx91@gmail.com。
参考文献
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