Fatigue Behavior of Large-Scale Reinforced Concrete Beams Strengthened in Flexure with Fiber-Reinforced Polymer Laminates
Publication: Journal of Composites for Construction
Volume 20, Issue 5
Abstract
The aim of the present research is the experimental investigation of the response of carbon-fiber-reinforced polymer (CFRP) strengthened reinforced concrete (RC) beams of large scale under fatigue loading. Reinforced concrete beams were cast for this purpose, both with rectangular and T cross-sections, with web dimensions of and 3,050 mm in length. Beams were strengthened in flexure with externally bonded CFRP laminate [externally bonded reinforcement (EBR)] or with CFRP laminates bonded into slits on the concrete cover surface [near-surface-mounted (NSM)]. Transverse CFRP sheets were placed on the shear spans of the beams to avoid fragile shear failure. All specimens were tested under fatigue loading, with load-unload cycles of 2 Hz frequency. Two different amplitudes of cycles were investigated. The different fatigue life and modes of failures are discussed. Beams subjected to the low loading range, simulating the service loads of a bridge beam, could sustain more than 2 million cycles. Beams subjected to the high loading range, according to the maximum limit of industry standards, presented fatigue failure of the reinforcing steel in cycles less than . The ratio of the axial rigidity of the tensile steel bar to the axial rigidity of fiber-reinforced polymer (FRP) strengthening plays a significant role in extending the fatigue life of steel and thus of RC FRP strengthened beams. The lower the ratio, the higher the fatigue life of the retrofitted member. NSM strengthening may maintain a full bond with the concrete substrate even after the fatigue fracture of steel bars. Therefore, it may provide residual capacity to the retrofitted member to survive detrimental collapse.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors wish to thank Sika Hellas S.A. for providing the FRP materials and resins, DUTh RC Laboratory staff for the assistance in the construction, casting, and preparation of the specimens, and DUTh RC Laboratory and Sika Hellas S.A. staff for the assistance in the FRP implementation.
References
ACI (American Concrete Institute). (1997). “Considerations for design of concrete structures subjected to fatigue loading.” ACI 215R-74, Farmington Hills, MI.
ACI (American Concrete Institute). (2008). “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures.” ACI 440.2R-08, Farmington Hills, MI.
Aidoo, J., Harries, K. A., and Petrou, M. F. (2004). “Fatigue behavior of carbon fiber reinforced polymer-strengthened reinforced concrete bridge girders.” J. Compos. Constr., 501–509.
Barros, J. A. O., and Fortes, A. S. (2005). “Flexural strengthening of concrete beams with CFRP laminates bonded into slits.” Cem. Concr. Compos., 27(4), 471–480.
Bizindavyi, L., Neale, K. W., and Erki, M. A. (2003). “Experimental investigation of bonded fiber reinforced polymer-concrete joints under cyclic loading.” J. Compos. Constr., 127–134.
CSA (Canadian Standards Association). (2006). “Canadian highway bridge design code.” CAN/CSA S6-06, Mississauga, ON, Canada.
De Lorenzis, L., and Nanni, A. (2002). “Bond between near-surface mounted FRP rods and concrete in structural strengthening.” ACI Struct. J., 99(2), 123–133.
Ekenel, M., Rizzo, A., Myers, J. J., and Nanni, A. (2006). “Flexural fatigue behavior of reinforced concrete beams strengthened with FRP fabric and procured laminate systems.” J. Compos. Constr., 433–442.
Ferrier, E., Bigaud, D., Clément, J. C., and Hamelin, P. (2011). “Fatigue-loading effect on RC beams strengthened with externally bonded FRP.” Constr. Build. Mater., 25(2), 539–546.
Gheorgiu, C., Labossiere, P., and Proulx, J. (2007). “Response of CFRP strengthened beams under fatigue with different load amplitudes.” Constr. Build. Mater., 21(4), 756–763.
Gussenhoven, R., and Brena, S. (2005). “Fatigue behavior of reinforced concrete beams strengthened with different FRP laminate configurations.” Proc., 7th Fiber Reinforced Polymers for Reinforced Concrete Structures (FRPRCS7).” Vol. 230, American Concrete Institute (ACI), Farmington Hills, MI, 613–630.
Heffernan, P. J., and Erki, M. A. (2004). “Fatigue behavior of reinforced concrete beams strengthened with carbon fiber reinforced plastic laminates.” J. Compos. Constr., 132–140.
Papakonstantinou, C. G., Petrou, M. F., and Harries, K. A. (2001). “Fatigue behavior of RC beams strengthened with GFRP sheets.” J. Compos. Constr., 246–253.
Sena-Cruz, J., and Barros, J. A. O. (2004). “Modeling of bond between near surface mounted CFRP laminate strips and concrete.” Comput. Struct., 82(17-19), 1513–1521.
Sena-Cruz, J. M., Barros, J. A. O., Coelho, M. R. F., and Silva, L. F. F. T. (2011). “Efficiency of different techniques in flexural strengthening of RC beams under monotonic and fatigue loading.” Constr. Build. Mater., 29, 175–182.
Senthilnath, P. S., Belarbi, A., and Myers, J. J. (2001). “Performance of CFRP strengthened reinforced concrete beams in the presence of delaminations and lap slices under fatigue loading.” Proc., Int. Conf. on Composites in Construction (CCC-2001), Porto, Portugal, 323–328.
Teng, J. G., De Lorenzis, L., Wang, B., Li, R., Wong, T., and Lam, L. (2006). “Debonding failures of RC beams strengthened with near surface mounted CFRP strips.” J. Compos. Constr., 92–105.
Toutanji, H., Zhao, L., Deng, Y., Zhang, Y., and Balaguru, P. (2006). “Cyclic behavior of RC beams strengthened with carbon fiber sheets bonded by inorganic matrix.” J. Mater. Civ. Eng., 28–35.
Wahab, N., Soudki, K. A., and Topper, T. (2011). “Mechanics of bond fatigue behavior of concrete beams strengthened with NSM CFRP rods.” J. Compos. Constr., 934–942.
Wang, Y. C., Lee, M. G., and Chen, B. C. (2007). “Experimental study of FRP-strengthened RC bridge girders subjected to fatigue loading.” Compos. Struct., 81(4), 491–498.
Williams, G., and Higgins, C. (2008). “Fatigue of diagonally cracked RC girders repaired with CFRP.” J. Bridge Eng., 24–33.
Yost, J. R., Gross, S. P., and Deitch, M. J. (2007). “Fatigue behavior of concrete beams strengthened in flexure with near surface mounted CFRP.” 8th Int. Symp. on Fiber Reinforced Polymer Reinforcement for Reinforced Concrete Structures (FRPRCS-8), Univ. of Patras, Patras, Greece, 1–8.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 20 • Issue 5 • October 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Sep 5, 2015
Accepted: Jan 15, 2016
Published online: Mar 24, 2016
Discussion open until: Aug 24, 2016
Published in print: Oct 1, 2016
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.