Vol. 16, No. 1, pp. 47-54 (2020)
LATERAL TORSIONAL BUCKLING STRENGTH OF STEEL I BEAMS
WITHIN PREFLEXED BEAMS IN PRE- BENDING STAGE
Lin-jie Tian 1, Zhe Li 2, Ming Yang 1, *, Shan Chang 1 and Jian-qi Qian 1
1 School of Transportation, Southeast University, Nanjing, China
2 Tongji Architectural Design(Group) Co., Ltd, Shanghai, China
*(Corresponding author: E-mail:This email address is being protected from spambots. You need JavaScript enabled to view it.)
Received: 25 April 2019; Revised: 20 October 2019; Accepted: 24 October 2019
DOI:10.18057/IJASC.2020.16.1.6
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ABSTRACT
Attention should be paid to the lateral torsional buckling (LTB) of steel I-beams in pre-bending stage for the usage of preflexed beams. This paper develops analytical and numerical models for predicting LTB strength of steel I-beams arranged with different numbers of lateral braces and subjected to two movable concentrated loads in pre-bending stage. The different out-of-plane deformations of beam segments under assumed and actual conditions caused by bending moment distribution were considered, and the modified Rayleigh-Ritz method was proposed based on the constraint effect of adjacent beam segments. ABAQUS 2017 program was used for finite element analysis (FEA), and then have a comparison with the theoretical analysis. Additionally, LTB strength of steel I-beams with different parameters were investigated, and the effect of every selected parameter was described. The comparison results show that the modified Rayleigh-Ritz method has better applicability and accuracy under different parameters than the traditional Rayleigh-Ritz method, which can be used for selecting parameters and predicting LTB strength of steel I-beams in pre-bending stage.
KEYWORDS
Preflexed beam, Lateral torsional buckling, Modified Rayleigh-Ritz method, Lateral brace, LTB critical moment
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