Experimental Study on Wedge Anchorage Performance of Prestressed BFRP Laminates for Flexural Strengthening of Reinforced Concrete Components
Publication: Journal of Composites for Construction
Volume 27, Issue 5
Abstract
This study investigated the anchoring effect of wedge anchorages on prestressed basalt fiber–reinforced polymer (BFRP) laminates. Compared with traditional carbon fiber–reinforced polymer (CFRP) laminates, BFRP laminates have a larger ultimate fracture strain, lower elastic modulus, and smaller prestress loss, making them cost-effective prestressed materials. Fifteen fiber-reinforced polymer (FRP) laminate–anchorage assemblies were prepared to investigate the effects of FRP type, anchorage type, mat type, and presetting load level on the static tensile behavior of FRP laminate–anchorage assemblies. The differences in the failure modes, load versus displacement (L–D) curves, and strain development of the FRP laminates were analyzed. The results demonstrated that, first, the anchorage efficiency of the CFRP laminate–anchorage assembly was higher than that of BFRP. Since the elastic modulus and transverse shear strength of the BFRP laminates were much lower than those of the CFRP laminates, the application of the traditional CFRP anchorage easily damaged the BFRP laminates. Therefore, a specific design and optimization are required for BFRP laminate anchorages. Second, an anchorage with a retracted stressing end wedge was prone to obtain higher normal stress and thus achieve a higher anchoring capacity. Third, the sandpaper mat improved the friction between the FRP laminate and wedges and alleviated the stress concentration phenomenon of the FRP laminate at the stressing end of the anchorage. Finally, an increased presetting load on the wedges could slightly improve the assemblies’ ultimate bearing capacity and stiffness; however, the enhanced presetting load aggravated the stress concentration phenomenon at the stressing end of the anchorage.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This work was supported by the National Science Foundation of China (Grant No. 6305001037) and the Scientific Research Foundation of the Graduate School of Southeast University (Grant no. YBPY21).
Notation
The following symbols are used in this paper:
- b
- nominal width of the FRP laminate;
- bb0
- barrel width;
- bb1
- right width of the barrel;
- bb2
- middle width of the barrel;
- bb3
- left width of the barrel;
- E
- elastic modulus of the FRP laminate;
- Fu
- ultimate bearing capacity of the FRP laminate;
- fu
- ultimate tensile strength of the FRP laminate;
- hb0
- thickness of the barrel;
- hb1
- upper thickness of the barrel;
- hb2
- middle thickness of the barrel;
- hb3
- lower thickness of the barrel;
- hw
- thickness of the stressing end of the wedge;
- La
- length of the anchorage end;
- LFRP
- total length of the FRP laminate–anchorage assembly;
- Ls
- length of the strengthening plate end;
- Ltest
- length of the laminate without anchorage;
- lb0
- barrel length;
- lw0
- wedge length;
- lwe
- length of the wedge’s stressing end out of the barrel;
- length of the wedge’s free end out of the barrel;
- R
- stress ratio;
- t
- nominal thickness of the FRP laminate;
- αb
- slope angle of the barrel;
- αw
- slope angle of the wedge;
- strain at the measuring point;
- strain of strain gauge SG21;
- strain of strain gauge SG22;
- strain of strain gauge SG23;
- reference strain; and
- Δσ
- stress difference.
References
ACI (American Concrete Institute). 2004. Prestressing concrete structures with FRP tendons. ACI 440.4R-04. Farmington Hills, MI: ACI.
Aslam, M., P. Shafigh, M. Z. Jumaat, and S. N. R. Shah. 2015. “Strengthening of RC beams using prestressed fiber reinforced polymers—A review.” Constr. Build. Mater. 82: 235–256. https://doi.org/10.1016/j.conbuildmat.2015.02.051.
Bian, Z. N. 2021. “Research on flexural performance of notched steel beam strengthened with prestressed CFRP plates.” [In Chinese.] Master’s thesis, College of Civil and Transportation Engineering, Hohai Univ.
Bian, Z. N., H. T. Wang, and Y. S. Tang. 2020. “Numerical simulation and parametric analysis of the reverse-tension anchorage device for CFRP plate.” [In Chinese.] Henan Sci. 38 (9): 1433–1439.
Burtscher, S. L. 2008. “Wedge anchorage for CFRP strips.” J. Compos. Constr. 12 (4): 446–453. https://doi.org/10.1061/(asce)1090-0268(2008)12:4(446).
Carra, G., and V. Carvelli. 2015. “Long-term bending performance and service life prediction of pultruded Glass Fibre Reinforced Polymer composites.” Compos. Struct. 127: 308–315. https://doi.org/10.1016/j.compstruct.2015.03.049.
Chen, J. F., and J. G. Teng. 2001. “Anchorage strength models for FRP and steel plates bonded to concrete.” J. Struct. Eng. 127 (7): 784–791. https://doi.org/10.1061/(ASCE)0733-9445(2001)127:7(784).
Czaderski, C., and M. Motavalli. 2007. “40-Year-old full-scale concrete bridge girder strengthened with prestressed CFRP plates anchored using gradient method.” Composites, Part B 38 (7–8): 878–886. https://doi.org/10.1016/j.compositesb.2006.11.003.
Deng, J., M. Zhong, Y. Zheng, and M. Zhu. 2022. “Experimental study on the durability of steel anchors for prestressed CFRP laminates under accelerated galvanostatic corrosion.” Materials 15 (16): 5665. https://doi.org/10.3390/ma15165665.
El-Hacha, R., R. G. Wight, and M. F. Green. 2001. “Prestressed fibre-reinforced polymer laminates for strengthening structures.” Prog. Struct. Mater. Eng. 3 (2): 111–121. https://doi.org/10.1002/pse.76.
Figeys, W., E. Verstrynge, K. Brosens, L. Van Schepdael, J. Dereymaeker, D. Van Gemert, and L. Schueremans. 2011. “Feasibility of a novel system to prestress externally bonded reinforcement.” Mater. Struct. 44 (9): 1655–1669. https://doi.org/10.1617/s11527-011-9725-x.
Garcez, M. R., G. L. C. P. Silva Filho, and U. Meier. 2012. “Post-strengthening of reinforced concrete beams with prestressed CFRP strips. Part 1: Analysis under static loading.” Rev. IBRACON Estruturas Mater. 5 (3): 343–361. https://doi.org/10.1590/S1983-41952012000300006.
Garden, H. N., and L. C. Hollaway. 1998a. “An experimental study of the failure modes of reinforced concrete beams strengthened with prestressed carbon composite plates.” Composites, Part B 29 (4): 411–424. https://doi.org/10.1016/S1359-8368(97)00043-7.
Garden, H. N., and L. C. Hollaway. 1998b. “An experimental study of the influence of plate end anchorage of carbon fibre composite plates used to strengthen reinforced concrete beams.” Compos. Struct. 42 (2): 175–188. https://doi.org/10.1016/S0263-8223(98)00070-1.
Jumaat, M. Z., and M. D. Ashraful Alam. 2010. “Experimental and numerical analysis of end anchored steel plate and CFRP laminate flexurally strengthened reinforced concrete (r. c.) beams.” Int. J. Phys. Sci. 5 (2): 132–144.
Kalfat, R., R. Al-Mahaidi, and S. T. Smith. 2013. “Anchorage devices used to improve the performance of reinforced concrete beams retrofitted with FRP composites: State-of-the-art review.” J. Compos. Constr. 17 (1): 14–33. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000276.
Kotynia, R., R. Walendziak, I. Stoecklin, and U. Meier. 2011. “RC slabs strengthened with prestressed and gradually anchored CFRP strips under monotonic and cyclic loading.” J. Compos. Constr. 15 (2): 168–180. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000081.
Li, C., and G. Xian. 2019. “Design optimization and experimental validation of a novel wedge-shaped bond anchorage system for prestressed CFRP plates.” Polym. Test. 75: 167–174. https://doi.org/10.1016/j.polymertesting.2019.02.001.
Liu, C., X. Wang, J. Shi, L. Liu, and Z. Wu. 2021. “Experimental study on the flexural behavior of RC beams strengthened with prestressed BFRP laminates.” Eng. Struct. 233: 111801. https://doi.org/10.1016/j.engstruct.2020.111801.
Michels, J., J. Sena-Cruz, C. Czaderski, and M. Motavalli. 2013. “Structural strengthening with prestressed CFRP strips with gradient anchorage.” J. Compos. Constr. 17 (5): 651–661. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000372.
Mohee, F. M., and A. Al-Mayah. 2018. “Effect of barrel, wedge material and thickness on composite plate anchor performance through analytical, finite element, experimental and 3D prototype investigations.” Eng. Struct. 175: 138–154. https://doi.org/10.1016/j.engstruct.2018.08.003.
Mohee, F. M., A. Al-Mayah, and A. Plumtree. 2016. “Anchors for CFRP plates: State-of-the-art review and future potential.” Composites, Part B 90: 432–442. https://doi.org/10.1016/j.compositesb.2016.01.011.
Oehlers, D. J., P. Visintin, and W. Lucas. 2016. “Fundamental mechanics governing FRP-retrofitted RC beams with anchored and prestressed FRP plates.” J. Compos. Constr. 20 (6): 04016047. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000710.
Piątek, B., T. Siwowski, J. Michałowski, and S. Błażewicz. 2020. “Development of bonded/riveted steel anchorages of prestressed CFRP strips for concrete strengthening.” Materials 13 (10): 2217. https://doi.org/10.3390/ma13102217.
Piątek, B., T. Siwowski, J. Michałowski, and S. Błażewicz. 2021. “Experimental research on hybrid anchorages of prestressed composite strips for structural strengthening.” J. Compos. Mater. 55 (24): 3539–3550. https://doi.org/10.1177/00219983211020349.
SAC (Standardization Administration of the People's Republic of China). 2005. Fiber-reinforced plastics composites—Determination of tensile properties. [In Chinese.] GB/T 1447-2005. Beijing: SAC.
SAC (Standardization Administration of the People's Republic of China). 2010. Metallic materials—Tensile testing—Part 1: Method of test at room temperature. [In Chinese.] GB/T 228.1-2010. Beijing: SAC.
Shi, J., X. Wang, L. Zhang, Z. Wu, and Z. Zhu. 2022. “Composite-wedge anchorage for fiber-reinforced polymer tendons.” J. Compos. Constr. 26 (2): 04022005. https://doi.org/10.1061/(ASCE)CC.1943-5614.0001194.
Sim, J., C. Park, and D. Y. Moon. 2005. “Characteristics of basalt fiber as a strengthening material for concrete structures.” Composites, Part B 36 (6–7): 504–512. https://doi.org/10.1016/j.compositesb.2005.02.002.
Siwowski, T., B. Piątek, P. Siwowska, and A. Wiater. 2020. “Development and implementation of CFRP post-tensioning system for bridge strengthening.” Eng. Struct. 207: 110266. https://doi.org/10.1016/j.engstruct.2020.110266.
Spadea, G., F. Bencardino, F. Sorrenti, and R. N. Swamy. 2015. “Structural effectiveness of FRP materials in strengthening RC beams.” Eng. Struct. 99: 631–641. https://doi.org/10.1016/j.engstruct.2015.05.021.
Wang, H. T, Z. N. Bian, M. S. Chen, L. Hu, and Q. Wu. 2023. “Flexural strengthening of damaged steel beams with prestressed CFRP plates using a novel prestressing system.” Eng. Struct. 284. https://doi.org/10.1016/j.engstruct.2023.115953.
Wang, X., J. Shi, J. Liu, L. Yang, and Z. Wu. 2014. “Creep behavior of basalt fiber reinforced polymer tendons for prestressing application.” Mater. Des. 59: 558–564. https://doi.org/10.1016/j.matdes.2014.03.009.
Wang, X., J. Shi, G. Wu, L. Yang, and Z. Wu. 2015. “Effectiveness of basalt FRP tendons for strengthening of RC beams through the external prestressing technique.” Eng. Struct. 101: 34–44. https://doi.org/10.1016/j.engstruct.2015.06.052.
Wight, R. G., M. F. Green, and M.-A. Erki. 2001. “Prestressed FRP sheets for poststrengthening reinforced concrete beams.” J. Compos. Constr. 5 (4): 214–220. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:4(214).
Woo, S.-K., J.-W. Nam, J.-H.-J. Kim, S.-H. Han, and K. J. Byun. 2008. “Suggestion of flexural capacity evaluation and prediction of prestressed CFRP strengthened design.” Eng. Struct. 30 (12): 3751–3763. https://doi.org/10.1016/j.engstruct.2008.06.013.
Wu, Z. S., X. Wang, and G. Wu. 2012. “Advancement of structural safety and sustainability with basalt fiber reinforced polymers.” In Proc., Canada Int. Conf. on Education, 15–29. Rome, Italy: International Institute for FRP in Construction (IIFC).
Yang, J., M. Johansson, M. Al-Emrani, and R. Haghani. 2021. “Innovative flexural strengthening of RC beams using self-anchored prestressed CFRP plates: Experimental and numerical investigations.” Eng. Struct. 243: 112687. https://doi.org/10.1016/j.engstruct.2021.112687.
Zhou, L. P. 2012. “Research on hinge-type anchor tensioning of prestressed FRP sheets technique.” [In Chinese.] Master’s thesis, School of Civil Engineering, Chongqing Jiaotong Univ.
Information & Authors
Information
Published In
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Dec 18, 2022
Accepted: May 12, 2023
Published online: Jul 11, 2023
Published in print: Oct 1, 2023
Discussion open until: Dec 11, 2023
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.