摘要:
研究了轴心受压T形截面考虑翼缘和腹板相互约束的截面局部屈曲,给出了局部屈曲临界应力的公式。将确定板件分类等级的方法应用到截面分类上,以腹板和翼缘宽厚比相关关系的形式给出了4类截面S1,S2,S3和S4的分类标准。观察曲线形状发现,曲线可分成传统分类区和扩展分类区。在传统分类区,翼缘和腹板进行独立分类;在扩展分类区,腹板的宽厚比限值可以放宽,但是翼缘的宽厚比限值必须更严,以考虑翼缘对腹板的约束作用带来的对翼缘本身的削弱。为此对4类截面提出了宽厚比限值的计算公式,以供规范编修时参考。
关键词:
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截面分类 /
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T形截面 /
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翼缘 /
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腹板 /
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临界应力
Abstract:
Buckling of T-Sections under compression is studied analytically considering the interaction between flange and web. Formulas for the critical stress of the cross-section are presented. Extending the classification philosophy of steel plates to steel cross-sections, the paper obtained the interaction curves between the limiting values of the width-to-thickness ratios of flanges and webs for 4 classes(S1, S2, S3, S4) of the T-section. Based on the interaction curves, it is revealed that the classifications are composed of two regions: one is the traditional, in which flange and web are classified independently; the other is the extended region for which the width-to-thickness ratio of the web is relaxed and correspondingly the flange's width-to-thickness ratio is more stringent to reflect the weakening effect to the flange itself due to providing restraint to the web. For 4 classes of T-section, the limiting values are presented for possible references of codification.