Behaviour of Cold Formed Built - Up Steel Compression Member

The use of cold-formed thin-walled steel structural members has increased in recent years. Especially, Cold-formed steel columns are widely used in the construction industry due to their lightweight, easy installation, erection and economy. The strength and efficiency of cold-formed steel profiles depends on the cross-sectional shape, which controls the three fundamental buckling modes: local, distortional and global. As most of their sections are open with only one symmetrical axis, they would likely fail by twisting and interacted with the other buckling modes such as local and distortional buckling. In order to improve the ultimate strength of columns, a built-up column section with distinct shape was selected from the detailed study of Literatures and three specimens of thickness 1.6mm were fabricated with different lengths 500mm, 600mm and 700mm. Consequently, buckling behaviour of built up steel members was investigated theoretically with Direct Strength Method (with the help of CuFSM) as well as experimentally and the results were compared with the buckling modes obtained numerically using ANSYS software and it is found that the ultimate load carrying capacity of the column increases with the decrease of slenderness ratio and finally a new innovative and economical column element was presented.

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Load-Carrying Capacity of Cold-Formed Steel Columns with Complicated Section under Eccentric Compression Loading

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.838-841.601 ◽

2013 ◽

Vol 838-841 ◽

pp. 601-604

Author(s):

Chun Gang Wang ◽

Zi Feng Xu ◽

Zhuang Nan Zhang ◽

Yu Fei Cao

Keyword(s):

Carrying Capacity ◽

Ultimate Load ◽

Load Carrying Capacity ◽

Buckling Modes ◽

Compression Loading ◽

Steel Columns ◽

Eccentric Compression ◽

Load Carrying ◽

Cold Formed Steel ◽

Ultimate Load Carrying Capacity

This paper studied 30 cold-formed steel columns with three different sections and eleven different eccentricities under eccentric compression loading by nonlinear finite element analysis using program ANSYS. Effects of the above parameters on ultimate load-carrying capacity, buckling modes, the distribution of stress and strain, and deflection behavior of channels with complex edge stiffeners under eccentric compression loading were investigated. The result shows that influence of the effective centroid offset on carrying capacity under eccentric compression loading can not be ignored. The maximum of ultimate load-carrying capacity appeared when effective eccentricity was 0mm, and decreased with the increase of the value of effective eccentricity. Sections influence on load-carrying capacity under negative eccentric compression loading. Web stiffening can improve load-carrying capacity which the eccentricity near the web side. Sections influence on buckling modes. web stiffening can effectively avoid local buckling.

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Interaction between local and distortional buckling modes in cold-formed steel members subjected to pure bending

International Journal of Computer Applications in Technology ◽

10.1504/ijcat.2011.045818 ◽

2011 ◽

Vol 42 (4) ◽

pp. 279

Author(s):

Jing Yin ◽

Xiao Xiong Zha ◽

Long Yuan Li

Keyword(s):

Distortional Buckling ◽

Pure Bending ◽

Buckling Modes ◽

Steel Members ◽

Cold Formed Steel

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Buckling Analysis of C-Section Cold-Formed Steel Purlins under Uplift Loadings

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.627.124 ◽

2014 ◽

Vol 627 ◽

pp. 124-128

Author(s):

Xiao Feng Wu ◽

Yin Hai Zhao ◽

Jue Zhu ◽

Chong Sun ◽

Chao Xie

Keyword(s):

Ultimate Load ◽

Wind Loading ◽

Analysis Model ◽

Element Analysis ◽

Finite Element Analysis Model ◽

Steel Members ◽

Load Carrying ◽

Cold Formed Steel ◽

Ultimate Load Carrying Capacity ◽

Partially Restrained

In this paper, a finite element analysis model for C-section cold-formed steel members partially restrained in its rotational direction by sheeting is established. Analyses are carried out using the model to examine the ultimate load carrying capability of the members when they are subjected to uplift wind loading. The analyses consider the material and geometric nonlinearities. The numerical analysis results show that the sheeting restraints have significant influence on the structural performance of the C-section purlin. It can increase the ultimate load carrying capacity evidently.

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Experiment and Design Method on Cold-Formed Thin-Walled Steel Lipped Channel Columns with Slotted Web Holes Under Axial Compression

The Open Civil Engineering Journal ◽

10.2174/1874149501711010244 ◽

2017 ◽

Vol 11 (1) ◽

pp. 244-257 ◽

Cited By ~ 2

Author(s):

Xingyou Yao

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Ultimate Strength ◽

Test Results ◽

Distortional Buckling ◽

Steel Columns ◽

Cold Formed Steel ◽

Thin Walled ◽

Shell Finite Element ◽

The Web

Background: Cold-formed steel structural sections used in the walls of residential buildings and agricultural facilities are commonly C-shaped sections with web holes. These holes located in the web of sections can alter the elastic stiffness and the ultimate strength of a structural member. The objective of this paper is to study the buckling mode and load-carrying capacity of cold-formed thin-walled steel column with slotted web holes. Methods: Compression tests were conducted on 26 intermediate length columns with and without holes. The tested compressive members included four different kinds of holes. For each specimen, a shell finite element Eigen-buckling analysis and nonlinear analysis were also conducted. The influence of the slotted web hole on local and distortional buckling response had also been studied. The comparison on ultimate strength between test results and calculated results using Chinese cold-formed steel specification GB50018-2002, North American cold-formed steel specification AISI S100-2016, and nonlinear Finite Element method was made. Result: Test results showed that the distortional buckling occurred for intermediate columns with slotted holes and the ultimate strength of columns with holes was less than that of columns without holes. The ultimate strength of columns decreased with the increase in transverse width of hole in the cross-section of member. The Finite element analysis results showed that the web holes could influence on the elastic buckling stress of columns. The shell finite element could be used to model the buckling modes and analysis the ultimate strength of members with slotted web holes. The calculated ultimate strength shows that results predicted with AISI S100-2016 and analyzed using finite element method are close to test results. The calculated results using Chinese code are higher than the test results because Chinese code has no provision to calculate the ultimate strength of members with slotted web holes. Conclusion: The calculated method for cold-formed thin-walled steel columns with slotted web holes are proposed based on effective width method in Chinese code. The results calculated using the proposed method show good agreement with test results and can be used in engineering design for some specific cold-formed steel columns with slotted web holes studied in this paper.

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Mechanical Behavior of Damaged H-Section Steel Structure

Advances in Civil Engineering ◽

10.1155/2021/8247670 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Xibing Hu ◽

Rui Chen ◽

Yuxuan Xiang ◽

Yafang Chen ◽

Qingshan Li

Keyword(s):

Cross Sections ◽

Elastic Moduli ◽

Mechanical Test ◽

Steel Structure ◽

Steel Structures ◽

Computational Accuracy ◽

Cross Sectional ◽

Steel Columns ◽

Steel Members ◽

The Cross

Steel structures are usually damaged by disasters. According to the influence law of the damage on the elastic modulus of steel obtained by the mechanical test of damaged steel, the average elastic moduli of H-section steel members were analyzed. The equations for calculating the average elastic moduli of damaged H-section steel members at different damage degrees were obtained. By using the analytical cross-sectional method, the cross-sectional M-Φ-P relationships and the dimensionless parameter equations of the H-sections in the full-sectional elastic distribution, single-sided plastic distribution, and double-sided plastic distribution were derived. On the basis of the cross-sectional M-Φ-P relationships and dimensionless parameters of actual steel members, the approximate calculation equations for the damaged cross sections were obtained. The Newmark method was used to analyze the deformation of damaged steel columns. Analytical results show good agreement with the test results. The equations and methods proposed in this study have high computational accuracy, and these can be applied to the cross-sectional M-Φ-P relationships and deformation calculation of damaged steel members.

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A new formulation for distortional buckling stress in cold-formed steel members

Journal of Constructional Steel Research ◽

10.1016/j.jcsr.2005.09.011 ◽

2006 ◽

Vol 62 (7) ◽

pp. 716-722 ◽

Cited By ~ 36

Author(s):

Murat Pala

Keyword(s):

Distortional Buckling ◽

Buckling Stress ◽

Steel Members ◽

Cold Formed Steel ◽

New Formulation

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Lipped channel cold-formed steel columns under local-distortional buckling mode interaction

Thin-Walled Structures ◽

10.1016/j.tws.2018.12.041 ◽

2019 ◽

Vol 137 ◽

pp. 251-270 ◽

Cited By ~ 6

Author(s):

Gustavo Y. Matsubara ◽

Eduardo de M. Batista ◽

Guilherme C. Salles

Keyword(s):

Mode Interaction ◽

Distortional Buckling ◽

Buckling Mode ◽

Steel Columns ◽

Cold Formed Steel

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Experimental Study and Direct Strength Method for Cold-Formed Steel Built-Up I-Sectional Columns under Axial Compression

Mathematical Problems in Engineering ◽

10.1155/2021/5565125 ◽

2021 ◽

Vol 2021 ◽

pp. 1-22

Author(s):

Xingyou Yao

Keyword(s):

Finite Element ◽

Axial Compression ◽

Numerical Study ◽

Experimental Results ◽

Distortional Buckling ◽

Cross Sectional ◽

Direct Strength Method ◽

Comparison Results ◽

Cold Formed Steel ◽

Interactive Buckling

The objective of this paper is to investigate the buckling behavior and design method of the ultimate strength for the cold-formed steel (CFS) built-up I-sectional columns under axial compression which failed in distortional buckling and interactive buckling. A total of 56 CFS built-up I-sectional columns subjected to axial compression were tested, and the different buckling modes and ultimate strengths were analyzed in detail by varying the thickness, the length, the spacing of screws, the end fastener group, and the cross-sectional dimensions of CFS built-up I-sectional columns. It was shown in the test that noticeable interaction of local and distortional buckling or interaction of local, distortional, and global buckling was observed for the built-up I-sectional columns with different lengths and cross-sectional dimensions. A finite element model (FEM) was developed and validated with experimental results. A further parametric study has been conducted including different cross sections and slenderness ratios for the built-up I-sectional columns. The load-carrying capacities obtained from the experimental and numerical study were used to investigate the feasibility of the current direct strength method (DSM) when DSM was applied to CFS built-up I-sectional columns. The comparison results showed that the current DSM is not safe for CFS built-up columns failed in distortional buckling and interactive buckling. Therefore, the improved design formulas were proposed, and their accuracy was verified by using finite element analysis (FEA) and experimental results of CFS built-up I-sectional columns subjected to axial compression.

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