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Flexural and shear behaviour of lightweight RC beams strengthened by NSM GFRP bars

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Journal of Building Pathology and Rehabilitation Aims and scope Submit manuscript

Abstract

This research has presented an experimental study to improve the flexural and shear strengths of lightweight reinforced concrete (LWRC) beams using near surface mounted (NSM) glass fiber reinforced polymer (GFRP) bars. Utilizing NSM GFRP bars in shear strengthening of the LWRC beams is elatively new practical approach and this study is on of the first experimental studies conducted about this topic. The main parameters investigated are location, number, diameter, bond length, spacing, angle of inclination, and material of the NSM bars used to strengthen the LWRC beams. The LWRC beams specimens were composed by completely replacing natural coarse aggregate with lightweight expanded clay aggregate (LECA) in the concrete mixture. The experimental program consists of twelve LWRC beams with cross-section dimensions of 160 × 250 mm (width × height) and total length of 1700 mm. The beam specimens were divided into two groups according to the strengthening objective: the first group consists of six LWRC beams strengthened in flexure; while the second group includes six LWRC beams strengthened in shear. One beam in each group was unstrengthened and considred as control beam, while the other specimens were strengthened by NSM GFRP bars in different arrangements and configurations. All LWRC beams are subject to two points loading until failure. The experimental results have shown that using side near surface mounted (SNSM) GFRP bar improves the ultimate load capacity of the LWRC beam by about 30% compared to control beam. Furthe, the experimental results revealed that when 50% of the epoxy adhesive is replacement by cement mortar at the beam mid-span, the ultimate load capacity of the NSM strengthened LWRC beams is almost similar to that when 100% epoxy adhesive was used. It was also observed that the inclined alignment of the NSM GFRP bar increases the loading capacity by about 149% compared to that of the control beam with failure mode being changed from shear to flexural failure.

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Data availability

The data that support the findings of this study are available on request from the corresponding author.

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Authors and Affiliations

  1. Civil Engineering Department, University of Al-Qadisiyah, Ad Diwaniyah, Iraq

    Haitham Al-Thairy & Anees Jassim Youssef

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  1. Haitham Al-Thairy
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Manuscript title: Flexural and Shear Behaviour of Lightweight RC Beams Strengthened by NSM GFRP bars All persons who meet authorship criteria are listed as authors, and all authors certify that they have participated sufficiently in the work to take public responsibility for the content, including participation in the concept, design, analysis, writing, or revision of the manuscript. Furthermore, each author certifies that this material or similar material has not been and will not be submitted to or published in any other publication before its appearance in the Journal of Building Pathology and Rehabilitation Authorship contributions Category 1 Conception and design of study: Haitham Al-Thairy ;acquisition of data: Haitham Al-Thairy, Anees Jassim Youssef analysis and/or interpretation of data: Haitham Al-Thairy, Anees Jassim Youssef Category 2 Drafting the manuscript: Anees Jassim Youssef revising the manuscript critically for important intellectual content: Haitham Al-Thairy Category 3 Approval of the version of the manuscript to be published (the names of all authors must be listed): Haitham Al-Thairy , Anees Jassim Youssef Acknowledgements All persons who have made substantial contributions to the work reported in the manuscript (e.g., technical help, writing and editing assistance, general support), but who do not meet the criteria for authorship, are named in the Acknowledgements and have given us their written permission to be named. If we have not included an Acknowledgements, then that indicates that we have not received substantial contributions from non-authors. This statement is signed by all the authors (a photocopy of this form may be used if there are more than 10 authors): Author’s name (typed)Author’s signatureDate 16/12/2022 Haitham Al-Thairy Anees Jassim Youssef Author’s signature Date 16/12/2022

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Al-Thairy, H., Youssef, A.J. Flexural and shear behaviour of lightweight RC beams strengthened by NSM GFRP bars. J Build Rehabil 8, 31 (2023). https://doi.org/10.1007/s41024-023-00276-4

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  • DOI: https://doi.org/10.1007/s41024-023-00276-4

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