Design-Oriented Strength Model for FRP-Confined Concrete Members
Publication: Journal of Composites for Construction
Volume 16, Issue 6
Abstract
This study concerns assessing 20 existing models for predicting the compressive strength of concrete uniformly confined externally with composite materials. An extended database of 471 experiments on cylindrical concrete columns is utilized for the comparisons. The research classifies the experimental data in three distinguished subcategories according to the information available for the mechanical properties of the FRPs to investigate their effect on the divergences of the models. Apart from the use of the tensile strength obtained from coupon tests, the use of properties from the manufacturer data on FRP fibers can lead to minimum error of predicted strength of concrete externally wrapped or encased in FRP tubes. The study results in the proposal of an upgraded empirical model that indirectly encompasses the unique deformational characteristics of different Young’s moduli of FRP sheets and tubes. The model utilizes the strong linear dependence of the product of the varying effective strain at failure of the confining material () times the varying confinement effectiveness coefficient () on the Young’s modulus of the reinforcing fibers (). Thus, there is no need to estimate average empirical constant values for the or , and a more rational approach comes up that further restricts errors in strength modeling. The proposed model provides a prediction with absolute average error of 8.6% for wrapped columns and 6.3% for FRP-tube encased columns.
Get full access to this article
View all available purchase options and get full access to this article.
References
American Concrete Institute (ACI) Committee. (2008). “Guide for the design and construction of externally bonded frp systems for strengthening concrete structures.”, Farmington Hills, MI.
Berthet, J. F., Ferrier, E., and Hamelin, P. (2006). “Compressive behavior of concrete externally confined by composite jackets: Part B: Modeling.” Constr. Build. Mater., 20(5), 338–347.
Campione, G., and Miraglia, N. (2003). “Strength and strain capacities of concrete compression members reinforced with FRP.” Cement Concr. Compos., 25(1), 31–41.
Carey, S. A., and Harries, K. A. (2005). “Axial behavior and modeling of small-, medium- and large-scale circular sections confined with CFRP jackets.” ACI Struct. J., 102(4), 596–604.
Consiglio Nazionale Delle Ricerche (CNR). (2004). “Guide for the design and construction of externally bonded frp systems for strengthening existing structures.”, Italian National Research Council, Rome, Italy.
De Lorenzis, L., and Tepfers, R. (2003). “Comparative study of models on confinement of concrete cylinders with fiber-reinforced polymer composites.” J. Compos. Constr., 7(3), 219–234.
De Luca, A., Nardone, F., Matta, F., Nanni, A., Lignola, G., and Prota, A. (2011). “Structural evaluation of full-scale FRP-confined reinforced concrete columns.” J. Compos. Constr., 15(1), 112–123.
Eid, R., Roy, N., and Paultre, P. (2006). “Behaviour of circular reinforced concrete columns confined with transverse steel reinforcement and fiber-reinforced composite sheets.” fib Fédération Internationale du Béton Proc., 2nd Int. Congress, ID 10-10, fib CEP-FIP, Lausanne, Switzerland (Jun. 5–8, 2006).
EN 1992-1-1, Eurocode 2. “Design of concrete structures—Part 1-1: General rues and rules for buildings.” Brussels (Dec. 2004).
Fahmy, M. F. M., and Wu, Z. (2010). “Evaluating and proposing models of circular concrete columns confined with different FRP composites.” Composites, Part B, 41(3), 199–213.
Fardis, M. N., and Khalili, H. (1982). “FRP-encased concrete as a structural material.” Mag. Concr. Res., 34(121), 191–202.
Girgin, Z. C. (2009). “Modified failure criterion to predict ultimate strength of circular columns confined by different materials.” ACI Struct. J., 106(6), 800–809.
Harries, K. A., and Kharel, G. (2003). “Experimental investigation of the behavior of variably confined concrete.” Cement Concr. Res., 33(6), 873–880.
Jiang, T., and Teng, J. G. (2007). “Analysis-oriented stress–strain models for FRP–confined concrete.” Eng. Struct., 29(11), 2968–2986.
Karabinis, A. I., and Kiousis, P. D. (1994). “Effects of confinement on concrete columns: Plasticity approach.” J. Struct. Eng., 120(9), 2747–2767.
Karabinis, A. I., and Kiousis, P. D. (1996a). “Plasticity computations for the design of the ductility of circular concrete columns.” Comput. Struct., 60(5), 825–835.
Karabinis, A. I., and Kiousis, P. D. (1996b). “Strength and ductility of rectangular concrete columns: A plasticity approach.” J. Struct. Eng., 122(3), 267–274.
Karabinis, A. I., and Rousakis, T. C. (2002). “Concrete confined by FRP material: A plasticity approach.” Eng. Struct., 24(7), 923–932.
Karbhari, V. M., and Gao, Y. (1997). “Composite jacketed concrete under uniaxial compression—verification of simple design equations.” J. Mater. Civ. Eng., 9(4), 185–193.
Kono, S., Inazumi, M., and Kaku, T. (1998). “Evaluation of confining effects of CFRP sheets on reinforced concrete members.” Proc., 2nd Int. Conf. on Composites in Infrastructure ICCI’98, Saadatmanesh, H., and Ehsani, M. R., eds., Tucson, AZ, 343–355.
Kumutha, R., Vaidyanathan, R., and Palanichamy, M. S. (2007). “Behaviour of reinforced concrete rectangular columns strengthened using GFRP.” Cement Concr. Compos., 29(8), 609–615.
La Tegola, A., and Manni, O. (1999). “Experimental investigation on concrete confined by fiber reinforced polymer and comparison with theoretical model.” Proc., 4th Int. RILEM Symp. on Non-Metallic (FRP) Reinforcement for Concrete Structures (FRPRCS-4), RILEM, Bagneux, France, 217–228.
Lam, L., and Teng, J. G. (2002). “Strength models for fiber-reinforced plastic-confined concrete.” J. Struct. Eng., 128(5), 612–623.
Lam, L., and Teng, J. G. (2003). “Design-oriented stress-strain model for FRP-confined concrete.” Constr. Build. Mater., 17(6–7), 471–489.
Lam, L., and Teng, J. G. (2004). “Ultimate condition of fiber reinforced polymer-confined concrete.” J. Compos. Constr., 8(6), 539–548.
Mander, J. B., Priestley, M. J. N., and Park, R. (1998). “Theoretical stress-strain model for confined concrete.” ASCE J. Struct. Eng., 114(8), 1804–1826.
Matthys, S. (2000). “Structural behaviour and design of concrete members strengthened with externally bonded FRP reinforcement.” Ph.D. thesis, Ghent Univ., Ghent, Belgium.
Matthys, S., Toutanji, H., Audenaert, K., and Taerwe, L. (2005). “Axial load behavior of large-scale columns confined with FRP composites.” ACI Struct. J., 102(2), 258–267.
Mirmiran, A., and Shahawy, M. (1997). “Behavior of concrete columns confined by fiber composites.” J. Struct. Eng., 123(5), 583–590.
Rakitzis, T. D. (2010). “Comparative investigation of existing models on concrete confined by fiber reinforced polymers (FRP).” M.Sc. thesis, Civil Engineering Dept., Democritus Univ. of Thrace, Xanthi, Greece (in Greek).
Richart, F. E., Brandtzaegm, A., and Brown, R. L. (1928). “A study of the failure of concrete under combined compressive stresses.”, Univ. of Illinois, Engineering Experimental Station, Champaign, IL.
Rousakis, T., and Karabinis, A. (2010). “Fiber reinforced polymer confinement of bridge columns suffering from premature bars’ buckling—strength empirical model.” 34th Int. Association for Bridge and Structural Engineering Symp., Venice, 48–55.
Rousakis, T. C. (2001). “Experimental investigation of concrete cylinders confined by carbon FRP sheets, under monotonic and cyclic axial compression load.”, Division of Building Technology, Chalmers Univ. of Technology, Göteborg, Sweden.
Rousakis, T. C. (2005). “Mechanical behaviour of concrete confined by composite materials.” Ph.D. thesis, Democritus Univ. of Thrace, Civil Engineering Dept., Xanthi, Greece (in Greek).
Rousakis, T. C., and Karabinis, A. I. (2008). “Substandard reinforced concrete members subjected to compression: FRP confining effects.” Mater. Struct., 41(9), 1595–1611.
Rousakis, T. C., and Karabinis, A. I. (2012). “Adequately FRP confined reinforced concrete columns under axial compressive monotonic or cyclic loading.” Mater. Struct., 45(7), 957–975.
Rousakis, T. C., Karabinis, A. I., Kiousis, P. D., and Tepfers, R. (2008). “Analytical modelling of plastic behaviour of uniformly FRP confined concrete members.” Composites, Part B, 39(7–8), 1104–1113.
Saafi, M., Toutanji, H. A., and Li, Z. (1999). “Behavior of concrete columns confined with fiber reinforced polymer tubes.” ACI Mater. J., 96(4), 500–509.
Samaan, M., Mirmiram, A., and Shahawy, M. (1998). “Model of concrete confined by fiber composites.” J. Struct. Eng., 124(9), 1025–1031.
Smith, S. T., Kim, S. J., and Zhang, H. (2010). “Behavior and effectiveness of FRP wrap in the confinement of large concrete cylinders.” J. Compos. Constr., 14(5), 573–582.
Spoelstra, M. R., and Monti, G. (1999). “FRP-confined concrete model.” J. Compos. Constr., 3(3), 143–150.
Teng, J. C., and Lam, L. (2004). “Behavior and modeling of fiber reinforced polymer-confined concrete.” J. Struct. Eng., 130(11), 1713–1723.
Teng, J. G., Jiang, T., Lam, L., and Luo, Y. Z. (2009). “Refinement of a design-oriented stress–strain model for FRP-confined concrete.” J. Compos. Constr., 13(4), 269–278.
Teng, J. G., Yu, T., Wong, Y. L., and Dong, S. L. (2007). “Hybrid FRP-concrete-steel tubular columns: Concept and behavior.” Constr. Build. Mater., 21(4), 846–854.
Toutanji, H. (1999). “Stress-strain characteristics of concrete columns externally confined with advanced fiber composite sheets.” ACI Mater. J., 96(3), 397–404.
Toutanji, H., Han, M., Gilbert, J., and Matthys, S. (2010). “Behavior of large-scale rectangular columns confined with FRP composites.” J. Compos. Constr., 14(1), 62–71.
Vintzileou, E., and Panagiotidou, E. (2008). “An empirical model for predicting the mechanical properties of FRP-confined concrete.” Constr. Build. Mater., 22(5), 841–854.
Wang, L. M., and Wu, Y. F. (2008). “Effect of corner radius on the performance of CFRP-confined square concrete columns: Test.” Eng. Struct., 30(2), 493–505.
Wu, Y., and Wang, L. (2009). “A unified strength model for square and circular concrete columns confined by external jacket.” J. Struct. Eng., 135(3), 253–261.
Wu, Y.-F., and Zhou, Y.-W. (2010). “Unified strength model based on Hoek-Brown failure criterion for circular and square concrete columns confined by FRP.” J. Compos. Constr., 14(2), 175–184.
Xiao, Y., and Wu, H. (2000). “Compressive behavior of concrete confined by carbon fiber composite jackets.” J. Mater. Civ. Eng., 12(2), 139–146.
Xiao, Y., and Wu, H. (2003). “Compressive behavior of concrete confined by various types of FRP composite jackets.” J. Reinf. Plast. Compos., 22(13), 1187–1201.
Yang, X., Wei, J., Nanni, A., and Dharani, L. R. (2001). “Stresses in FRP laminates wrapped around corners.” Paper 088, Proc., ASC 16th Annual Conf., (CD-ROM) Hyer, M. W., and Loos, A. C., eds., Virginia Tech, Blacksburg, VA.
Youssef, M. N. (2003). “Stress strain model for concrete confined by FRP composites.” Ph.D. dissertation, Univ. of California-Irvine, Irvine, CA, 310.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 16 • Issue 6 • December 2012
Pages: 615 - 625
Copyright
© 2012 American Society of Civil Engineers.
History
Received: Sep 24, 2011
Accepted: Apr 3, 2012
Published online: Apr 10, 2012
Published in print: Dec 1, 2012
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.