Effect of Geometric Discontinuities on Strains in FRP-Wrapped Columns
Publication: Journal of Composites for Construction
Volume 14, Issue 2
Abstract
Extensive research on fiber-reinforced polymer (FRP) confinement strengthening for concrete columns has led to a good understanding of, and accurate models for, circular columns subjected to axial load. This research is being extended to noncircular and eccentrically loaded columns, steel tubular, and concrete-filled steel tubular columns. A significant gap in our understanding of all these columns, however, is that the apparent FRP strain at failure is significantly lower than the ultimate strain in a flat coupon test. There may be many factors contributing to this complex phenomenon. This paper shows that one of these factors is the geometrical discontinuities at the ends of the FRP wrap. The significance of the effect of discontinuities on the strain concentrations in the FRP wrap and the bonding adhesive is explored through an elastic finite-element analysis.
Get full access to this article
View all available purchase options and get full access to this article.
References
American Concrete Institute (ACI). (2008). “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures.” ACI 440.2R-08, Detroit.
Ansys. (2006). “Release 10.0 documentation for ANSYS.” Canonsburg, Pa.
Concrete-Society. (2004). “Design guidance for strengthening concrete structures using fibre composite materials.” Technical Report 55, 2nd Ed., Camberley, U.K.
Fam, A., Flisak, B., and Rizkalla, S. (2003). “Experimental and analytical modeling of concrete-filled fiber-reinforced polymer tubes subjected to combined bending and axial loads.” ACI Struct. J., 100(4), 399–509.
Fertis, D. G. (1996). Advanced mechanics of structures, CRC, Boca Raton, Fla.
Harries, K. A., and Carey, S. A. (2003). “Shape and ‘gap’ effects on the behavior of variably confined concrete.” Cem. Concr. Res., 33(6), 881–890.
Lam, L., and Teng, J. G. (2002). “Strength models for fiber-reinforced plastic-confined concrete.” J. Struct. Eng., 128, 612–623.
Lam, L., and Teng, J. G. (2003a). “Design-oriented stress-strain model for FRP-confined concrete.” Constr. Build. Mater., 17(6–7), 471–489.
Lam, L., and Teng, J. G. (2003b). “Design-oriented stress-strain model for FRP-confined concrete in rectangular columns.” J. Reinf. Plast. Compos., 22(13), 1149–1186.
Li, G., Maricherla, D., Singh, K., Pang, S. S., and John, M. (2006). “Effect of fiber orientation on the structural behavior of FRP wrapped concrete cylinders.” Compos. Struct., 74(4), 475–483.
Lignola, G., Prota, A., Manfredi, G., and Cosenza, E. (2008a). “Unified theory for confinement of RC solid and hollow circular columns.” Composites, Part B, 39(7–8), 1151–1160.
Lignola, G. P., Prota, A., Manfredi, G., and Cosenza, E. (2008b). “Effective strain in FRP jackets on circular RC columns.” Proc., 4th Int. Conf. Composites in Civil Engineering (CICE2008) (CD-ROM), Int. Institute for FRP in Construction (IIFC), Zurich, Switzerland, 6.
Mirmiran, A., and Shahawy, M. (1997). “Behavior of concrete columns confined by fiber composites.” J. Struct. Eng., 123(5), 583–590.
Mirmiran, A., Shahawy, M., Samaan, M., El Echary, H., Mastrapa, J. C., and Pico, O. (1998). “Effect of column parameters on FRP-confined concrete.” J. Compos. Constr., 2(4), 175–185.
Ranger, M., and Bisby, L. (2007). “Effects of load eccentricities on circular FRP-confined reinforced concrete columns.” Proc., Fibre Reinforced Polymers for Reinforced Concrete Structures (FRPRCS) 8, Univ. of Patras, Patras, Greece, 290–291.
Shahawy, M., Mirmiran, A., and Beitelman, T. (2000). “Tests and modeling of carbon-wrapped concrete columns.” Composites, Part B, 31(6–7), 471–480.
Tabbara, M., and Karam, G. (2008). “Numerical investigation of failure localization and stress concentrations in FRP wrapped concrete cylinders.” Proc., Advanced Composites Materials in Bridges and Structures (ACMBS) V, Canadian Society for Civil Engineering (CSCE), Winnipeg, Canada.
Takeuti, A. R., de Hanai, J. B., and Mirmiran, A. (2008). “Preloaded RC columns strengthened with high-strength concrete jackets under uniaxial compression.” Mater. Struct., 41(7), 1251–1262.
Teng, J. G., Chen, J. F., Smith, S. T., and Lam, L. (2002). FRP-strengthened RC structures, Wiley, New York.
Teng, J. G., Chen, J. F., Smith, S. T., and Lam, L. (2003). “Behaviour and strength of FRP-strengthened RC structures: A state-of-the-art review.” Proc., Inst. Civ. Eng., Struct. Build., 156(1), 51–62.
Teng, J. G., and Hu, Y. M. (2005). “Enhancement of seismic resistance of steel tubular columns by FRP jacketing.” Proc., 3rd Int. Conf. Composites in Construction, Univ. of Lyon, Lyon, France.
Teng, J. G., and Hu, Y. M. (2006). “Theoretical model for FRP-confined circular concrete-filled steel tubes under axial compression.” Proc., 3rd Int. Conf. FRP Composites in Civil Engineering (CICE 2006), Univ. of Miami, Miami.
Teng, J. G., Huang, Y. L., Lam, L., and Ye, L. P. (2007). “Theoretical model for fiber-reinforced polymer-confined concrete.” J. Compos. Constr., 11, 201.
Teng, J. G., and Jiang, T. (2008). “Strengthening of reinforced concrete (RC) columns with fibre-reinforced polymer (FRP) composites.” Strengthening and rehabilitation of civil infrastructures using fibre-reinforced polymer (FRP) composites, Woodhead, Cambridge, U.K., 158–194.
Teng, J. G., and Lam, L. (2004). “Behavior and modeling of fiber reinforced polymer-confined concrete.” J. Struct. Eng., 130, 1713.
Vinson, J. R., and Sierakowski, R. L. (2002). The behavior of structures composed of composite materials, Springer, New York.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 14 • Issue 2 • April 2010
Pages: 136 - 145
Copyright
© 2010 ASCE.
History
Received: Dec 29, 2008
Accepted: Jul 8, 2009
Published online: Jul 13, 2009
Published in print: Apr 2010
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.