Lateral-torsional buckling analysis of steel I-beams in pre-bending stage based on modified Rayleigh-Ritz method

被引：0
|
作者：
Tian L. [1 ]
Ju X. [2 ]
Li Z. [3 ]
Chang S. [1 ]
Yang M. [1 ]
机构：
[1] School of Transportation, Southeast University, Nanjing
[2] China Road and Bridge Corporation, Beijing
[3] Tongji Architectural Design(Group) Co., Ltd., Tongji University, Shanghai
来源：
Dongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Southeast University (Natural Science Edition) | 2019年 / 49卷 / 04期
关键词：
Critical moment; Energy method; Lateral brace; Lateral-torsional buckling; Steel I-beam;
D O I：
10.3969/j.issn.1001-0505.2019.04.010
中图分类号：
学科分类号：
摘要：
In order to accurately analyze the law of lateral-torsional buckling (LTB) of steel I-beams in the pre-bending stage, a mathmatical model of a steel I-beam, which was subjected to two movable concentrated loads and with different numbers of lateral braces, was established. The restraint effect of beam segments caused by the segmental arrangement of lateral braces was considered, and the solution of the Rayleigh-Ritz method was modified. Additionally, different sizes and loading parameters of steel I-beams were selected as analysis indexes, and a large number of simulation analyses were carried out by the finite element method ABAQUS to verify the modified Rayleigh-Ritz method. The comparison results show that as the number of lateral braces increases, the error of the traditional Rayleigh-Ritz method increases gradually. The modified Rayleigh-Ritz method can minimize the relative error of solution results of the traditional Rayleigh-Ritz method by about 13%, and the modified Rayleigh-Ritz method has proved to be of good accuracy and applicability. The results of the parameter study show that in the pre-bending stage, the LTB critical moments of steel I-beams decrease with the increase in the value of concentrated loading location parameter, and increase slowly with the increase in the number of lateral braces. The safety factor of LTB increases with the increase in the number of lateral braces and the degree of monosymmetry. © 2019, Editorial Department of Journal of Southeast University. All right reserved.
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页码：679 / 687
页数：8
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