Finite-Element Analysis and Strength Model for IC Debonding in FRP-Strengthened RC Beams
Publication: Journal of Composites for Construction
Volume 22, Issue 5
Abstract
Intermediate crack (IC) debonding is one of the most dominant failure modes associated with reinforced concrete beams strengthened with fiber-reinforced polymer (FRP) plates. To obtain a better understanding of the mechanism of IC debonding, a comprehensive finite-element (FE) model based on the smeared-crack method is proposed to predict IC debonding failure. This model adopts a crack band model for concrete and incorporates a bond–slip relationship between the steel bars and surrounding concrete, as well as between the FRP plates and concrete substrate. The proposed model is found to be capable of accurately predicting the appearance, development and distribution of cracks in concrete. Furthermore, the concentration of interfacial slip and abrupt changes in the interfacial shear stress and FRP plate strain due to cracking can be predicted accurately, and IC debonding is successfully captured. Comparisons between the numerical and experimental results of 35 beams confirm that the proposed FE model is appropriate for predicting the IC debonding of the strengthened beams. Finally, a simple and accurate model of the FRP debonding strain is proposed based on the FE interfacial shear stress distribution. The accuracy of the model is verified by comparing the strength model with the results of 116 beam tests.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors would like to acknowledge the financial support from the National Key Research and Development Program of China (2016YFC0701400), the National Natural Science Foundation of China (Grant No. 51525801), the National Natural Science Foundation of China (Grant No. 51528802), and OVM Machinery Co., Ltd.
References
ABAQUS. 2013. ABAQUS 6.13 user’s manual. Providence, RI: ABAQUS.
ACI (American Concrete Institute). 2008a. Building code requirements for structural concrete and commentary. ACI 318. Farmington Hills, MI: ACI.
ACI (American Concrete Institute). 2008b. Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures. ACI 440.2R. Farmington Hills, MI: ACI.
Barbato, M. 2009. “Efficient finite element modelling of reinforced concrete beams retrofitted with fibre reinforced polymers.” Comput. Struct. 87 (3–4): 167–176. https://doi.org/10.1016/j.compstruc.2008.11.006.
Bazant, Z. P., and J. Planas. 1998. Fracture and size effect in concrete and other quasibrittle materials. Boca Raton, FL: CRC Press.
Beber, A. J., A. C. Filho, and J. L. Campagnolo. 2001. “CFRP in the strengthening of reinforced concrete beams.” In Proc., Int. Conf. on FRP Composites in Civil Engineering, edited by J. G. Teng, 391–398. Amsterdam, Netherlands: Elsevier Science.
Bizindavyi, L., and K. W. Neale. 1999. “Transfer lengths and bond strengths for composites bonded to concrete.” J. Compos. Constr. 3 (4): 153–160. https://doi.org/10.1061/(ASCE)1090-0268(1999)3:4(153).
Brosens, K., and D. van Gemert. 1997. “Anchoring stresses between concrete and carbon fibre reinforced laminates.” In Vol. 1 of Proc., 3rd Int. Symp. on Non-Metallic (FRP) Reinforcement for Concrete Structure, 271–278. Sapporo, Japan: Japan Concrete Institute.
Buyukozturk, O., O. Gunes, and E. Karaca. 2004. “Progress on understanding debonding problems in reinforced concrete and steel members strengthened using FRP composites.” Constr. Build. Mater. 18 (1): 9–19. https://doi.org/10.1016/S0950-0618(03)00094-1.
Camata, G., E. Spacone, and R. Zarnic. 2007. “Experimental and nonlinear finite element studies of RC beams strengthened with FRP plates.” Compos. B Eng. 38 (2): 277–288. https://doi.org/10.1016/j.compositesb.2005.12.003.
CEB-FIP. 1993. CEB-FIP model code 90. London: Thomas Telford.
CECS (China Association for Engineering Construction Standardization). 2003. Technical specification for strengthening concrete structure with carbon fiber reinforced polymer laminate. CECS 146. Beijing: China Planning Press.
Ceroni, F., and A. Prota. 2001. “Experimental behavior of RC beams strengthened by FRP sheets.” In Proc., Int. Conf. on Composites in Constructions, edited by J. Figueiras, L. Juvandes, and R. Faria, 499–504. Rotterdam, Netherlands: A.A. Balkema.
Chan, T. K., and M. Niall. 2001. Strengthening of one-way slabs using carbon fibre plates: The effect of preload. Singapore: Nanyang Technology Univ.
Chen, G. M., J. G. Teng, and J. F. Chen. 2011. “Finite-element modeling of intermediate crack debonding in FRP-plated RC beams.” J. Compos. Constr. 15 (3): 339–353. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000157.
Chen, G. M., J. G. Teng, J. F. Chen, and Q. G. Xiao. 2015. “Finite element modeling of debonding failures in FRP-strengthened RC beams: A dynamic approach.” Comput. Struct. 158: 167–183. https://doi.org/10.1016/j.compstruc.2015.05.023.
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).
Chen, W. F. 1982. Plasticity in reinforced concrete. New York: McGraw-Hill.
Coronado, C. A., and M. M. Lopez. 2006. “Sensitivity analysis of reinforced concrete beams strengthened with FRP laminates.” Cem. Concr. Compos. 28 (1): 102–114. https://doi.org/10.1016/j.cemconcomp.2005.07.005.
Elsanadedy, H. M., H. Abbas, Y. A. Al-Salloum, and T. H. Almusallam. 2014. “Prediction of intermediate crack debonding strain of externally bonded FRP laminates in RC beams and one-way slabs.” J. Compos. Constr. 18 (5): 04014008. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000462.
Fang, T. Q. 2002. “Study on U-shaped sheet behavior of anti-debonding in the concrete beam reinforced flexurally with FRP.” Master’s thesis, Tsinghua Univ.
Fanning, P., and O. Kelly. 2001. “Ultimate response of RC beams strengthened with CFRP plates.” J. Compos. Constr. 5 (2): 122–127. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:2(122).
Fu, B., G. M. Chen, and J. G. Teng. 2017. “Mitigation of intermediate crack debonding in FRP-plated RC beams using FRP U-jackets.” Compos. Struct. 176: 883–897. https://doi.org/10.1016/j.compstruct.2017.05.049.
Gao, B., J.-K. Kim, and C. K. Y. Leung. 2004. “Experimental study on RC beams with FRP strips bonded with rubber modified resins.” Compos. Sci. Technol. 64 (16): 2557–2564. https://doi.org/10.1016/j.compscitech.2004.05.016.
Garden, H. N., R. J. Quantrill, L. C. Hollaway, A. M. Thorne, and G. A. R. Parke. 1998. “An experimental study of the anchorage length of carbon fiber composite plates used to strengthen reinforced concrete beams.” Constr. Build. Mater. 12 (4): 203–219. https://doi.org/10.1016/S0950-0618(98)00002-6.
Hilber, H. M. 1976. Analysis and design of numerical integration methods in structural dynamics. Berkeley, CA: Univ. of California.
Hollaway, L. C., and J. G. Teng. 2008. Strengthening and rehabilitation of civil infrastructures using fibre-reinforced polymer (FRP) composites. Cambridge, UK: Woodhead Publishing.
Hordijk, D. A. 1991. “Local approach to fatigue of concrete.” Ph.D. thesis, Delft Univ. of Technology.
Jendele, L., and J. Cervenka. 2006. “Finite element modelling of reinforcement with bond.” Comput. Struct. 84 (28): 1780–1791. https://doi.org/10.1016/j.compstruc.2006.04.010.
JSCE (Japan Society of Civil Engineers). 2001. Recommendations for upgrading of concrete structures with use of continuous fiber sheets: Concrete engineering series 41, 256. Osaka, Japan: JSCE.
Lee, S., and S. Moy. 2007. “A method for predicting the flexural strength of RC beams strengthened with carbon fiber reinforced polymer.” J. Reinforc. Plast. Compos. 26 (14): 1383–1401. https://doi.org/10.1177/0731684407079372.
Lopez-Gonzalez, J. C., J. Fernandez-Gomez, E. Diaz-Heredia, J. C. López-Agüí, and P. Villanueva-Llaurado. 2016. “IC debonding failure in RC beams strengthened with FRP: Strain-based versus stress increment-based models.” Eng. Struct. 118: 108–124. https://doi.org/10.1016/j.engstruct.2016.03.024.
Lu, X. Z., J. G. Teng, L. P. Ye, and J. J. Jiang. 2005. “Bond-slip models for FRP sheets/plates bonded to concrete.” Eng. Struct. 27 (6): 920–937. https://doi.org/10.1016/j.engstruct.2005.01.014.
Lu, X. Z., J. G. Teng, L. P. Ye, and J. J. Jiang. 2007. “Intermediate crack debonding in FRP-strengthened RC beams: FE analysis and strength model.” J. Compos. Constr. 11 (2): 161–174. https://doi.org/10.1061/(ASCE)1090-0268(2007)11:2(161).
Maalej, M., and K. S. Leong. 2005. “Effect of beam size and FRP thickness on interfacial shear stress concentration and failure mode of FRP-strengthened beams.” Compos. Sci. Technol. 65 (7–8): 1148–1158. https://doi.org/10.1016/j.compscitech.2004.11.010.
Mohammadi, T., B. Wan, K. A. Harries, and M. E. Sweriduk. 2017. “Bond behavior of FRP-concrete in presence of intermediate crack debonding failure.” J. Compos. Constr. 21 (5): 04017018. 10.1061/(ASCE)CC.1943-5614.0000797.
Niu, H. D., A. Vasquez, and V. M. Karbhari. 2006. “Effect of material configuration on strengthening of concrete slabs by CFRP composites.” Compos. Part B 37 (2–3): 213–226. https://doi.org/10.1016/j.compositesb.2005.05.015.
Niu, H. D., and Z. S. Wu. 2005. “Numerical analysis of debonding mechanisms in FRP-strengthened RC beams.” Comput. Aided Civ. Infrastruct. Eng. 20 (5): 354–368. https://doi.org/10.1111/j.1467-8667.2005.00402.x.
Oehlers, D. J., P. Visintin, and W. Lucas. 2015. “Flexural strength and ductility of FRP-plated RC beams: Fundamental mechanics incorporating local and global IC debonding.” J. Compos. Constr. 20 (2): 04015046. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000610.
Rahimi, H., and A. Hutchinson. 2001. “Concrete beams strengthened with externally bonded FRP plates.” J. Compos. Constr. 5 (1): 44–56. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:1(44).
Rots, J. G. 1988. “Computational modeling of concrete fracture.” Ph.D. thesis, Delft Univ. of Technology.
Saadatmanesh, H., and M. Ehsani. 1991. “RC beams strengthened with GFRP plates. I: Experimental study.” J. Struct. Eng. 117 (11): 3417–3433. https://doi.org/10.1061/(ASCE)0733-9445(1991)117:11(3417).
Saenz, L. P. 1964. “Discussion of ‘Equation for the stress-strain curve of concrete’ by P. Desayi and S. Krishan.” J. Am. Concr. Inst. 61 (9): 1229–1235.
Said, H., and Z. Wu. 2008. “Evaluating and proposing models of predicting IC debonding failure.” J. Compos. Constr. 12 (3): 284–299. https://doi.org/10.1061/(ASCE)1090-0268(2008)12:3(284).
Seim, W., M. Hörman, V. Karbhari, and F. Seible. 2001. “External FRP poststrengthening of scaled concrete slabs.” J. Compos. Constr. 5 (2): 67–75. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:2(67).
Sena-Cruz, J. M., J. A. Barros, M. R. Coelho, and L. F. Silva. 2012. “Efficiency of different techniques in flexural strengthening of RC beams under monotonic and fatigue loading.” Constr. Build. Mater. 29: 175–182. https://doi.org/10.1016/j.conbuildmat.2011.10.044.
Spadea, G., R. Swamy, and F. Bencardino. 2001. “Strength and ductility of RC beams repaired with bonded CFRP laminates.” J. Bridge Eng. 6 (5): 349–355. https://doi.org/10.1061/(ASCE)1084-0702(2001)6:5(349).
Sun, R., E. Sevillano, and R. Perera. 2015. “A discrete spectral model for intermediate crack debonding in FRP-strengthened RC beams.” Compos. B Eng. 69: 562–575. https://doi.org/10.1016/j.compositesb.2014.10.017.
Teng, J. G., and J. F. Chen. 2009. “Mechanics of debonding in FRP-plated RC beams.” Proc. Inst. Civ. Eng. Struct. Build. 162 (5): 335–345. https://doi.org/10.1680/stbu.2009.162.5.335.
Teng, J. G., S. T. Smith, J. Yao, and J. F. Chen. 2003. “Intermediate crack-induced debonding in RC beams and slabs.” Constr. Build. Mater. 17 (6–7): 447–462. https://doi.org/10.1016/S0950-0618(03)00043-6.
Tumialan, G., P. Serra, A. Nanni, and A. Belarbi. 1999. “Concrete cover delamination in reinforced concrete beams strengthened with carbon fiber reinforced polymer sheets.” In Proc., 4th Int. Symp. on Fiber Reinforced Polymer Reinforcement for Reinforced Concrete Structures, edited by C. W. Dolan, S. H. Rizkalla, and A. Nanni, 725–735. Farmington Hills, MI: American Concrete Institute.
White, T., K. Soudki, and M. Erki. 2001. “Response of RC beams strengthened with CFRP laminates and subjected to a high rate of loading.” J. Compos. Constr. 5 (3): 153–162. https://doi.org/10.1061/(ASCE)1090-0268(2001)5:3(153).
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.
Xiong, G. J., H. Jiang, J. Z. Huang, J. Z. Yang, and H. C. Xie. 2001. “Behavior of concrete beams strengthened with hybrid carbon fiberglass fiber sheets.” In Proc., Int. Conf. on FRP Composites in Civil Engineering, edited by J. G. Teng, 407–414. Amsterdam, Netherlands: Elsevier Science.
Yang, D. S., S. K. Park, and K. W. Neale. 2009. “Flexural behaviour of reinforced concrete beams strengthened with prestressed carbon composites.” Compos. Struct. 88 (4): 497–508. https://doi.org/10.1016/j.compstruct.2008.05.016.
Yang, Z. J., J. F. Chen, and D. Proverbs. 2003. “Finite element modelling of concrete cover separation failure in FRP plated RC beams.” Constr. Build. Mater. 17 (1): 3–13. https://doi.org/10.1016/S0950-0618(02)00090-9.
Ye, L. P., W. Cui, and Q. R. Yue. 2001. “Analysis and calculation of flexural strength of RC members strengthened with CFRP sheet.” [In Chinese.] Build. Struct. 35 (3): 3–5. https://doi.org/10.19701/j.jzjg.2001.03.001.
Yi, W. J., and H. M. Huang. 2001. “Experimental study on the flexural behavior of RC beams strengthened with CFRP laminates.” In Proc., Int. Conf. on FRP Composites in Civil Engineering, edited by J. G. Teng, 399–406. Amsterdam, Netherlands: Elsevier Science.
You, Y. C., K. S. Choi, and J. Kim. 2012. “An experimental investigation on flexural behavior of RC beams strengthened with prestressed CFRP strips using a durable anchorage system.” Compos. B Eng. 43 (8): 3026–3036. https://doi.org/10.1016/j.compositesb.2012.05.030.
Zhang, A. H., W. L. Jin, and G. B. Li. 2006. “Behavior of preloaded RC beams strengthened with CFRP laminates.” J. Zhejiang Univ. Sci. A 7 (3): 436–444. https://doi.org/10.1631/jzus.2006.A0436.
Zhang, G. F., N. Kishi, H. Mikami, and M. Komuro. 2005. “A numerical prediction method for flexural behavior of RC beams reinforced with FRP sheet.” In Proc., Int. Symp. on Bond Behaviour of FRP in Structures (BBFS 2005), edited by J. F. Chen and J. G. Teng, 215–220. Kingston, ON, Canada: International Institute for FRP in Construction.
Zhao, M., H. D. Zhao, and Y. Zhang. 2002. “Experimental study on flexural RC members strengthened with CFRP fabrics.” [In Chinese.] Struct. Eng. 2: 52–58. https://doi.org/10.15935/j.cnki.jggcs.2002.02.010.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 22 • Issue 5 • October 2018
Copyright
©2018 American Society of Civil Engineers.
History
Received: Apr 20, 2017
Accepted: Mar 26, 2018
Published online: Jul 4, 2018
Published in print: Oct 1, 2018
Discussion open until: Dec 4, 2018
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.