Parametric study on lateral resistance and evaluation of seismic response modification factor-R of strap-braced cold-formed steel shear walls

Document Type : Research Paper

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Abstract

In this study, evaluation on lateral resistance and seismic response modification factor-R of strap-braced cold-formed steel shear walls is presented. Also, the results are compared with the prescibed values by the codes and standards. The structural parameters that are taken into account include: cross section of bracing straps, aspect ratio of the frames and studs’ spacing. In this study, the effects of nonlinear behavior of steel, geometric imperfection of cold formed sections and residual stresses induced by cold forming process are considered. The lateral strength and displacement of the frames will be determined by ANSYS finite element software. The results of the analysis show that the increase in straps’ cross-sections area and the ratio of width to height of the frame lead to increase of the frame capacity but changing the distances between the studs have no significant impact on the capacity of the frame. Also the response modification factors (R factors) of the studied frames are calculated in the range of 5.31 and 6.39. The results show that the prescribed R factors by the codes are conservative and can be improves, slightly.

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References

 
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Journal of Modeling in Engineering
Volume 15, Issue 49
September 2017
Pages 175-188

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History

  • Receive Date: 13 November 2014
  • Revise Date: 20 June 2015
  • Accept Date: 09 March 2016

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