剖分T型鋼壓桿整體失穩(wěn)問題研究*
熊曉莉，龐瑞
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熊曉莉，龐瑞（河南工業(yè)大學土木建筑學院， 鄭州 450001）［摘要］H型鋼剖分T型鋼壓桿在壓力作用下，屈曲性能有如下特點：一是當沿形心縱軸受壓而繞對稱軸屈曲時桿件將發(fā)生彎扭變形；二是當沿剪切中心軸受壓而繞對稱軸屈曲時彎曲變形與扭轉變形不再耦合。因此，形心受壓時的屈曲荷載低于剪切中心受壓時的屈曲荷載，上述結論對理想壓桿是適用的。然而，對于工程中具有初彎曲、初偏心以及殘余應力的剖分T型鋼壓桿而言，將壓力由形心軸移至剪切中心軸后，整體失穩(wěn)時的承載能力會降低，采用有限元建模計算剖分T型鋼壓桿承載力的分析結果也可證實上述結論。［關鍵詞］剖分T型鋼； 整體失穩(wěn)； 彎扭屈曲； 彎曲屈曲； 有限元中圖分類號：TU318，TU3l12文獻標識碼：A文章編號：1002-848X(2013)13-0058-05Study on overall instability of hot-rolled cut-T section strutsXiong Xiaoli, Pang Rui(Civil Engineering and Architecture Department, Henan University of Technology, Zhengzhou 450001, China)Abstract: Cut-T section obtained by splitting hot-rolled H section into two halves, has two features when buckles flexural-torsionally about axis of symmetry subject to centroid compression. On the other hand, when the force is applied at the shear center of the section, T-struts buckle either flexurally or torsionally without coupling of flexure with twisting. The buckling load of shear center loading is greater than that of centroid loading in elastic stage, which is suitable for ideal struts. However, for T-struts with defect such as fabrication error, load eccentricity and residual stress, the load capacity of overall instability decreases when moving the compression force from the centroid axis to the shear center axis. That peculiarity is verified by the nonlinear buckling analysis of load capacity of T-struts models by using ANSYS software.Keywords: Cut-T section; overall instability; flexural-torsional buckling; flexural buckling; finite element*“十二五”農村領域國家科技計劃資助項目（2011BAD03B00），鄭州市科技發(fā)展計劃資助項目（2010GYXM4900），河南工業(yè)大學高層次人才基金項目（2009BS046）。作者簡介：熊曉莉，博士，講師，Email：x_shanley@sina.com。參考文獻［1］CHEN SHAOFAN. Buckling of T-strut subject to compressive force on its shear center［J］. Journal of Constructional Steel Research，2007, 63：332-336.［2］陳紹蕃. 剖分T型鋼壓桿的屈曲性能和應用［J］. 建筑鋼結構進展，2005，7（4）：1-5.［3］TIMOSHENKO S P, GERE J M. Theory of elastic stability［M］. New York：McGraw-Hill，1961.［4］CHEN W F, ATSUTA T. Theory of Beam-Columns［M］. New York：McGraw-Hill，1977.［5］GB 50017—2003鋼結構設計規(guī)范［S］. 北京：中國計劃出版社，2003.［6］彭曉彤，陳紹蕃，顧強. 剖分T型鋼壓桿的彎扭屈曲試驗研究 ［J］. 建筑結構學報，2004，25(2)：44-48.
