The Combined Strengthening Effect of CFRP Wrapping and NSM CFRP Laminates on the Flexural Behavior of Post-Tensioning Concrete Girders Subjected to Partially Strand Damage

Authors

  • A. J. Daraj Department of Civil Engineering, University of Baghdad, Iraq
  • A. H. Al-Zuhairi Department of Civil Engineering, University of Baghdad, Iraq
Volume: 12 | Issue: 4 | Pages: 8856-8863 | August 2022 | https://doi.org/10.48084/etasr.5008

Abstract

The studies on unbonded post-tensioned concrete members strengthened with Carbon Fiber Reinforced Polymers (CFRPs) are limited and the effect of strengthening on the strain of unbonded pre-stressed steel is not well characterized. Estimating the flexural capacity of unbound post-tensioned members using the design methodology specified in the design guidelines for FRP strengthening techniques of bonded post-tensioned members does not provide a reliable evaluation. This study investigates the behavior of unbonded post-tensioned concrete members with partial strand damage (14.3% and 28.6% damage) and strengthened with CFRP laminates using a near-surface mounted technique with and without U-wrap anchorages. The experimental results showed that the use of CFRP laminates significantly affects strand strain, especially with the use of anchors. The CFRP reinforcement affected flexural strength, crack width, and midspan deflection. However, the flexural stiffness of strengthened members during the serviceability phases is critical as strand damage ratios increase. In comparison with the nondamaged girder, the NSM-CFRP laminates enhanced the flexural capacity by 11% and 7.7% corresponding to strand damage of 14.3% and 28.6% respectively. Additionally, semiempirical equations were proposed to predict the actual strain of unbonded strands whilst considering the effects of FRP laminates. The suggested equations are simple to apply and provide accurate predictions with little variance.

Keywords:

NSM-CFRP laminates, post-tensioned concrete, strand damage, strengthening

Downloads

Download data is not yet available.

References

C. E. Reed and R. J. Peterman, "Evaluation of Prestressed Concrete Girders Strengthened with Carbon Fiber Reinforced Polymer Sheets," Journal of Bridge Engineering, vol. 9, no. 2, pp. 185–192, Mar. 2004. DOI: https://doi.org/10.1061/(ASCE)1084-0702(2004)9:2(185)

O. Rosenboom, T. K. Hassan, and S. Rizkalla, "Flexural behavior of aged prestressed concrete girders strengthened with various FRP systems," Construction and Building Materials, vol. 21, no. 4, pp. 764–776, Apr. 2007. DOI: https://doi.org/10.1016/j.conbuildmat.2006.06.007

M. Di Ludovico, A. Prota, G. Manfredi, and E. Cosenza, "FRP Strengthening of Full-Scale PC Girders," Journal of Composites for Construction, vol. 14, no. 5, pp. 510–520, Oct. 2010. DOI: https://doi.org/10.1061/(ASCE)CC.1943-5614.0000112

F. El Meski and M. Harajli, "Flexural Behavior of Unbonded Posttensioned Concrete Members Strengthened Using External FRP Composites," Journal of Composites for Construction, vol. 17, no. 2, pp. 197–207, Apr. 2013. DOI: https://doi.org/10.1061/(ASCE)CC.1943-5614.0000330

L. Nguyen-Minh et al., "Flexural-strengthening efficiency of cfrp sheets for unbonded post-tensioned concrete T-beams," Engineering Structures, vol. 166, pp. 1–15, Jul. 2018. DOI: https://doi.org/10.1016/j.engstruct.2018.03.065

B. F. Abdulkareem, A. F. Izzet, and N. Oukaili, "Post-Fire Behavior of Non-Prismatic Beams with Multiple Rectangular Openings Monotonically Loaded," Engineering, Technology & Applied Science Research, vol. 11, no. 6, pp. 7763–7769, Dec. 2021. DOI: https://doi.org/10.48084/etasr.4488

H. M. Hekmet and A. F. Izzet, "Performance of Segmental Post-Τensioned Concrete Beams Exposed to High Fire Temperature," Engineering, Technology & Applied Science Research, vol. 9, no. 4, pp. 4440–4447, Aug. 2019. DOI: https://doi.org/10.48084/etasr.2864

S. Erdemlı Gunaslan, A. Karasin, and M. Öncü, "Properties of FRP Materials for Strengthening," International Journal of Innovative Science, Engineering & Technology, vol. 1, no. 9, pp. 656–660, Dec. 2014.

A. Soror, M. Tayel, and K. Heiza, "Post-tensioned Reinforced Concrete Beams Strengthend With Near Surface Mounted Technique," Dec. 2018.

A. Hosen, Z. Jumaat, K. M. ud Darain, and M. Obaydullah, "Innovative End Anchorage for Preventing Concrete Cover Separation of NSM Steel and CFRP bars Strengthened RC Beams," presented at the 6th Jordanian International Civil Engineering Conference, Amman, Jordan, Mar. 2015.

ACI-Committee-440.2R-17, ACI PRC-440.2-17: Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures. West Conshohocken, PA, USA: ACI, 2017.

A. M. Al-Hilali, A. F. Izzet, and N. Oukaili, "Static Shear Strength of a Non-Prismatic Beam with Transverse Openings," Engineering, Technology & Applied Science Research, vol. 12, no. 2, pp. 8349–8353, Apr. 2022. DOI: https://doi.org/10.48084/etasr.4789

A. H. Al-Zuhairi and A. I. Taj, "Effectiveness of Meso-Scale Approach in Modeling of Plain Concrete Beam," Journal of Engineering, vol. 24, no. 8, pp. 71–80, Jul. 2018. DOI: https://doi.org/10.31026/j.eng.2018.08.06

A. Hasnat, M. M. Islam, and A. F. M. S. Amin, "Enhancing the Debonding Strain Limit for CFRP-Strengthened RC Beams Using U-Clamps: Identification of Design Parameters," Journal of Composites for Construction, vol. 20, no. 1, Feb. 2016, Art. no. 04015039. DOI: https://doi.org/10.1061/(ASCE)CC.1943-5614.0000599

I. S. Shabana, I. A. Sharaky, A. Khalil, H. S. Hadad, and E. M. Arafa, "Flexural response analysis of passive and active near-surface-mounted joints: experimental and finite element analysis," Materials and Structures, vol. 51, no. 4, Jul. 2018, Art. no. 107. DOI: https://doi.org/10.1617/s11527-018-1232-x

A. H. Al-Zuhairi, A. H. Al-Ahmed, A. A. Abdulhameed, and A. N. Hanoon, "Calibration of a New Concrete Damage Plasticity Theoretical Model Based on Experimental Parameters," Civil Engineering Journal, vol. 8, no. 2, pp. 225–237, Feb. 2022. DOI: https://doi.org/10.28991/CEJ-2022-08-02-03

A. A. Abdulhameed et al., "The Behavior of Hybrid Fiber-Reinforced Concrete Elements: A New Stress-Strain Model Using an Evolutionary Approach," Applied Sciences, vol. 12, no. 4, Jan. 2022, Art. no. 2245. DOI: https://doi.org/10.3390/app12042245

A. Tam and F. N. Pannell, "The ultimate moment of resistance of unbonded partially prestressed reinforced concrete beams," Magazine of Concrete Research, vol. 28, no. 97, pp. 203–208, Dec. 1976. DOI: https://doi.org/10.1680/macr.1976.28.97.203

ACI Committee 318, ACI CODE-318-19: Building Code Requirements for Structural Concrete and Commentary. West Conshohocken, PA, USA: ACI, 2019.

H. Q. Abbas and A. H. Al‐Zuhairi, "Flexural Strengthening of Prestressed Girders with Partially Damaged Strands Using Enhancement of Carbon Fiber Laminates by End Sheet Anchorages," Engineering, Technology & Applied Science Research, vol. 12, no. 4, pp. 8884–8890, Aug. 2022.

Downloads

How to Cite

[1]
A. J. Daraj and A. H. Al-Zuhairi, “The Combined Strengthening Effect of CFRP Wrapping and NSM CFRP Laminates on the Flexural Behavior of Post-Tensioning Concrete Girders Subjected to Partially Strand Damage”, Eng. Technol. Appl. Sci. Res., vol. 12, no. 4, pp. 8856–8863, Aug. 2022.

Metrics

Abstract Views: 249
PDF Downloads: 127

Metrics Information
Bookmark and Share