Flexural and shear strengthening of RC beams with NSM technique and manually made CFRP bars

Document Type : Article

Authors

1 Faculty of Civil Engineering, Semnan University, Semnan, Iran , Postal Code: 3513119111

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

Abstract

In this paper, the efficiency of NSM method for both flexural and shear strengthening of RC beams were examined by applying an innovative manually made CFRP bar (MMFRP) as an alternative reinforcement composite material through experimental and numerical investigation. Experimental program was consisted of three inverted T-section RC flexural-dominated beams and three rectangular section RC shear-dominated beams with parameters of the length and anchoring of MMFRP bars and their inclination to the longitudinal axis of the beams. The structural performance of the tested beams and the Finite Element (FE) modeling approach including modes of failure, load-deflection response and ultimate load capacity are presented and discussed. Test results indicated that using proposed MMFRP bars significantly improved the flexural resistance and shear capacity of deficient concrete beams. Furthermore reduction of the crack width and increase in the quantity and propagation of new cracks was observed in strengthened beams compared to control beam.

Keywords

Main Subjects


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Volume 25, Issue 4 - Serial Number 4
Transactions on Civil Engineering (A)
July and August 2018
Pages 2012-2025
  • Receive Date: 14 September 2016
  • Revise Date: 05 January 2017
  • Accept Date: 11 March 2017