Experimental and Numerical Investigation of Reinforced Concrete Beam Retrofitted by CFRP Sheets

Document Type : Research Paper

Authors

1 Assistant Professor, Department of Civil Engineering, Firoozabad Branch, Meymand center, Islamic Azad University, Meymand, Iran.

2 Assistant Professor, Department of Civil Engineering, Beyza Branch, Islamic Azad University, Beyza, Iran.

10.22124/jcr.2023.23414.1606

Abstract

Currently, extensive studies are carried out on polymers reinforced with FRP sheets as reinforcement of structures both internally and externally. One of the conventional retrofitting methods for reinforced concrete beams is flexural strengthening of beams with CFRP materials. In this study, a full scale reinforced concrete beam was constructed and evaluated under four-point flexural test. Afterward, a same beam was retrofitted in flexural region by monolayer of CFRP. These experimental tests were carried out to be the basis of verification for numerical specimens. For numerical study, ABAQUS software was used for modeling and analysis of totally five retrofitted reinforced concrete beams. The results show that the fully retrofitted beam with CFRP laminate and U-shape wraps has the best performance in terms of capacity and delay for emergence of cracks. Its worth to say, flexural strengthening in the middle of beam has not notable result in capacity, though, could convey the failure mechanism to out of pure bending region.

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[1] ACI Committee 440. Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures: ACI 440.2 R-17. AmericanConcrete Institute, 2017.
[2] American Concrete Institute. Committee 440. Guide for the Design and Construction of Structural Concrete Reinforced with FRP Bars: ACI 440.1 R-06. American Concrete Institute, 2006.
[3] Saliha H, Bennetta C, Matamorosb A. Evaluation of novel combined CFRP-steel retrofit for repairing distortion-induced fatigue, Journal of Constructional Steel Research, 182: 106642, 2021.
[4] Eslamia A, Shayeghb H R, Moghavema A, Ronaghc H R, Experimental and analytical investigations of a novel end anchorage for CFRP flexural retrofits, Composites Part B: Engineering, 176: 107309, 2019.
[5] Falah Hassana H, et al, Flexural performance of concrete beams reinforced by gfrp bars and strengthened by cfrp sheets, Case Studies in Construction Materials, 13: e00417, 2020.
[6] Ali H, Assih J, Li A, Flexural capacity of continuous reinforced concrete beams strengthened or repaired by CFRP/GFRP sheets, International Journal of Adhesion and Adhesives, 104:102759, 2021.
[7] Elbana A, Junaid M T, Determination of flexural capacity for GFRP-reinforced concrete beams retrofitted using external CFRP sheet, Structures, 27: 1384-1395, 2020.
[8] Benmokrane B, Masmoudi R. Flexural response of concrete beams reinforced with FRP reinforcing bars. Struct J., 1996;93:46–55.
[9] M'Bazaa I, Missihoun M, Labossiere P. Strengthening of reinforced concrete beams with CFRP sheets. First International Conference on Composites in Infrastructure National Science Foundation National Sicence Foundation, 1996.
[10] Aghabozorgi, P., Khaloo, A. Numerical investigation of the effects of compression GFRP reinforcement on the flexural strength and ductility of reinforced concrete beams. Journal of Concrete Structures and Materials, 2018. 5(1), 31-45.
[11] Sharifi, Y., khojastefar, E. A method to assess capacity and deflection of flexural reinforced concrete members retrofitted with FRP. Journal of Concrete Structures and Materials, 2018. 3(2), 77-88.
[12] Baderan, M., Varaste Poor, H. An expremental method to prevent fast fracture phenomenon in bending of carbon and glass reinforced concrete beams. Journal of Concrete Structures and Materials, 2016. 1(2), 73-82.
[13] Talebzadeh, M., Rostamian, M. Modeling of reinforced beams with FRP sheet and its validation with laboratory results, Conference on Civil Engineering, Architecture and Urban Planning of the Islamic World, 2018.
[14] Kok S Leong, Effect Of Beam Size & FRP Thickness On Interfacial Shear Stress Concentration & Failure Mode In FRP Strengthened Beam, MS Thesis, Singapor, 2017.
[15] Pancha S., Norris T, Saadatmanesh H, Ehsani M. Improving The Serviceability Of Concrete Beams Using Carbon Fiber Reinforced Polymer (CFRP) Sheets. Federal Highway, 2016.
[16] Podoloski S., Taqieddin ZN Elasto-Plastic And Damage Modeling Of Reinforced Concrete, Ph.D. Dissertation, Dept. Civil & Environmental Engineering, Louisiana State Univ. Baton Rouge LA, 2018.
[17] Jarival M., Obaidat YT, Heyden S, Dahlblom O "The Effect Of CFRP And CFRP/ Concrete Interface Models When Modeling Retrofitted RC Beams With FEM" Journal Of Composite Structures, 2018.
[18] Najafgholipour, S.M. Dehghan, M. Khani, A. Heidari (2018) .The performance of lap splices in RC beams under inelastic reversed cyclic loading. Structures24 July, 2018.07.011.
[19] Garsia G., Heyden S, Dahlblom O "The Effect Of Cfrp And Cfrp/ Concrete Interface Models When Modeling Retrofitted Rc Beams With Fem" Journal Of Composite Structures. 2019.
[20] ZHANG, Yafang, et al. Experimental and numerical study on multi-impact performance of pre-damaged beams strengthened with CFRP. Engineering Structures, 2023, 285: 116034.‏
[21] ACI 318-19. Building Code Requirements for Structural Concrete. Reported By ACI Committee 318.