Abstract

The aim of this research is to enhance the torsional behavior of Square Hollow Steel (SHS) columns in existing structure through strengthening by Carbon Fiber Reinforced Polymer (CFRP). An appropriate modeling using the finite element software [ANSYS 14.5] is carried out to investigate the torsional behavior of strengthened steel Square Hollow Sections (SHS) with various thicknesses and calculate angles of twist. Analysis results showed a significant reduction in angles of twist for thin-walled sections after strengthening. The amount of increase in the maximum torsional capacity is related to the thickness of the original section. Thin-walled sections with large depth to thickness ratio (high D/t ratio) showed a larger improvement compared with the thicker-walled sections with low depth to thickness ratio (low D/t ratio) in the terms of maximum torsional capacity. The proposed numerical model is used in strengthening cold formed inclined columns of existing tents under the action of inclined forces and torsion. The strengthened model section capability against local buckling and twist is enhanced 64%.

Keywords:

Buckling behavior, CFRP strengthened, cold-formed steel, finite element, square hollow sections, Thinwalled and torsional load,

References

1. Ashvini, and S. Subramanian, 2015. Study on the performance of CFRP strengthened circular hollow steel sections. Int. J. Res. Eng. Technol., 4(6): 118-121.
   
2. Chahkand, N.A., M.Z. Jumaat, N.H. Ramli Sulong, X.L. Zhao and M.R. Mohammadizadeh, 2013. Experimental and theoretical investigation on torsional behaviour of CFRP strengthened square hollow steel section. Thin Wall. Struct., 68: 135-140.
   CrossRef    
3. MacDonald, M. and M.P. Kulatunga, 2013. Finite element analysis of cold-formed steel structural members with performations subjected to compression loading. Mech. Mech. Eng., 17(2): 127-139.
   Direct Link
4. Murray, N.M., 1984. Introduction to the Theory of Thin-Walled Structures. Clarendon Press, Oxford, USA.
   
5. Sharrock, J., C. Wu and X.L. Zhao, 2015. CFRP strengthened square hollow section subject to pure torsion. Proceeding of the 15th International Symposium on Tubular Structures. Rio de Janeiro, Brazil, pp: 661-668.
   CrossRef    
6. Sundarraja, M.C., P. Sriram and G.G. Prabhu, 2014. Strengthening of hollow square sections under compression using FRP composites. Adv. Mater. Sci. Eng., 2014: 19.
   CrossRef    
7. Wang, X., C. Wu and X.L. Zhao, 2013. Theoretical analysis of CFRP strengthened thin-walled steel Square Hollow Section (SHS) under torsion. Proceeding of the 4th Asia-Pacific Conference on FRP in Structures (APFIS 2013). Melbourne, Australia. December 11-13.
   Direct Link

Competing interests

The authors have no competing interests.

Open Access Policy

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The authors have no competing interests.