Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion

Box beams, with high torsional stiffness, light weight, and great structural resistance, are popularly used in the bridge structures. However, these box beams may fail suddenly due to increased traffic volumes and loads and diminished capacity from deterioration. Fiber-reinforced polymer (FRP) stren...

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Main Author: Shengqiang, Ma
Format: Thesis
Language:English
Published: 2017
Subjects:
Online Access:http://eprints.usm.my/45983/1/Reinforced%20Concrete%20Box%20Beam%20Strengthened%20By%20Carbon-Fiber-Reinforced%20Polymer%20Subjected%20To%20Combined%20Shear%20And%20Torsion.pdf
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spelling my-usm-ep.459832021-11-17T03:42:16Z Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion 2017-04-01 Shengqiang, Ma T Technology TA1-2040 Engineering (General). Civil engineering (General) Box beams, with high torsional stiffness, light weight, and great structural resistance, are popularly used in the bridge structures. However, these box beams may fail suddenly due to increased traffic volumes and loads and diminished capacity from deterioration. Fiber-reinforced polymer (FRP) strengthening technique has been studied and used in structures to improve the flexural and shear capacity of beams. However, very few strengthening studies have paid much attention to reinforced concrete (RC) box beams subjected to shear, torsion, and combined shear and torsion. Therefore, in this research, three sets of experiments on RC box beams strengthened with the carbon-fiber-reinforced polymer (CFRP) in shear, pure torsion, and combined shear and torsion were conducted. Based on experiments, the main aims are to: (a) predict the shear contribution of CFRP; (b) evaluate the strengthening effectiveness and predict the CFRP contribution to torsion; (c) investigate the behavior of strengthened box beams subjected combined shear and torsion and develop mathematical equations to predict strength. The fib Bulletin 14 model with the reduction coefficient proposed in effective strain of fiber could reliably predict the shear CFRP contribution to shear in strengthened RC box beam. In addition, it was found that the configuration of U-jacketing with longitudinal strips had a better performance in the torsional strengthening of RC box beam. One combined model had been revealed to be reliable and conservative in calculating the torsional strength of retrofitted RC beams. Further on, strengthening effectiveness of CFRP in combined shear and torsion to RC box beams was inversely proportional to torque-to-shear ratio. The derived equations with modified model of effective strain in fiber could give the desirable results of torsional strength to the strengthened or unstrengthened RC box beams subjected combined action. 2017-04 Thesis http://eprints.usm.my/45983/ http://eprints.usm.my/45983/1/Reinforced%20Concrete%20Box%20Beam%20Strengthened%20By%20Carbon-Fiber-Reinforced%20Polymer%20Subjected%20To%20Combined%20Shear%20And%20Torsion.pdf application/pdf en public phd doctoral Universiti Sains Malaysia Pusat Pengajian Kejuruteraan Awam
institution Universiti Sains Malaysia
collection USM Institutional Repository
language English
topic T Technology
T Technology
spellingShingle T Technology
T Technology
Shengqiang, Ma
Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion
description Box beams, with high torsional stiffness, light weight, and great structural resistance, are popularly used in the bridge structures. However, these box beams may fail suddenly due to increased traffic volumes and loads and diminished capacity from deterioration. Fiber-reinforced polymer (FRP) strengthening technique has been studied and used in structures to improve the flexural and shear capacity of beams. However, very few strengthening studies have paid much attention to reinforced concrete (RC) box beams subjected to shear, torsion, and combined shear and torsion. Therefore, in this research, three sets of experiments on RC box beams strengthened with the carbon-fiber-reinforced polymer (CFRP) in shear, pure torsion, and combined shear and torsion were conducted. Based on experiments, the main aims are to: (a) predict the shear contribution of CFRP; (b) evaluate the strengthening effectiveness and predict the CFRP contribution to torsion; (c) investigate the behavior of strengthened box beams subjected combined shear and torsion and develop mathematical equations to predict strength. The fib Bulletin 14 model with the reduction coefficient proposed in effective strain of fiber could reliably predict the shear CFRP contribution to shear in strengthened RC box beam. In addition, it was found that the configuration of U-jacketing with longitudinal strips had a better performance in the torsional strengthening of RC box beam. One combined model had been revealed to be reliable and conservative in calculating the torsional strength of retrofitted RC beams. Further on, strengthening effectiveness of CFRP in combined shear and torsion to RC box beams was inversely proportional to torque-to-shear ratio. The derived equations with modified model of effective strain in fiber could give the desirable results of torsional strength to the strengthened or unstrengthened RC box beams subjected combined action.
format Thesis
qualification_name Doctor of Philosophy (PhD.)
qualification_level Doctorate
author Shengqiang, Ma
author_facet Shengqiang, Ma
author_sort Shengqiang, Ma
title Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion
title_short Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion
title_full Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion
title_fullStr Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion
title_full_unstemmed Reinforced Concrete Box Beam Strengthened By Carbon-Fiber-Reinforced Polymer Subjected To Combined Shear And Torsion
title_sort reinforced concrete box beam strengthened by carbon-fiber-reinforced polymer subjected to combined shear and torsion
granting_institution Universiti Sains Malaysia
granting_department Pusat Pengajian Kejuruteraan Awam
publishDate 2017
url http://eprints.usm.my/45983/1/Reinforced%20Concrete%20Box%20Beam%20Strengthened%20By%20Carbon-Fiber-Reinforced%20Polymer%20Subjected%20To%20Combined%20Shear%20And%20Torsion.pdf
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