Investigation of Effectiveness of Key Parameters on Seismic Performance RC Columns Strengthened with Near-Surface Mounted (NSM) Method

Document Type : Original Article

Authors

1 Associate Professor, Faculty of Civil Engineering, Semnan University, Semnan, Iran

2 Faculty of Civil Engineering, Semnan University, Semnan, Iran

Abstract

In this paper, a strengthening method based on embedded carbon fiber reinforced polymer (CFRP) strips in near surface on concrete cover was applied for improving flexural capacity of reinforced concrete columns with low strength compressive concrete subjected lateral cyclic loads. The debonding phenomena is prevented in this suggested method and the strip capacity is completely used and there is more protection against fire. In order to investigate the flexural behavior of near surface mounted (NSM) strengthened RC columns, a finite element method is sued. poly-linear behavior of concrete and steel was used. There was good similarity between finite element and experimental results that indicates suggested model was calibrated. The new models consisting of different variables such as embedded steel bar diameter, concrete strength, and the numbers of CFRP strips were considered. The test results show that by using the NSM technique, the flexural strength and lateral load capacity of the columns increase significantly. The numerical results were also compared with the results obtained from the analytical study that was conducted based on strain compatibility. A good agreement between analytical and experimental results was observed.

Keywords

References

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Journal of Concrete Structures and Materials
Volume 1, Issue 2 - Serial Number 2
December 2016
Pages 5-18

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History

  • Receive Date: 01 August 2017
  • Revise Date: 12 September 2017
  • Accept Date: 05 November 2017

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