Simplified Nonlinear Analysis of Strengthened Concrete Beams Based on a Rigorous Approach
Publication: Journal of Structural Engineering
Volume 130, Issue 7
Abstract
The external fiber reinforced polymer (FRP) flexural and shear strengthening of reinforced concrete beams is a well-established technique for structural rehabilitation and upgrade. In the present work, an analytical solution is developed for the load–deflection calculation of FRP strengthened simple beams at any load stage. The solution assumes a trilinear moment–curvature response characterized by the flexural crack initiation, steel yielding, and ultimate capacity. Closed form expressions are presented for the case of simple beams subjected to three-point bending, four-point bending, and uniform load. These expressions are derived for beams with any extent of uncracked, postcracked, and postyielded regions along their span. An extensive parametric study is conducted yielding unique linear relationships between basic sectional moments of inertia and their corresponding effective beam values for a wide range of geometric and material variables considered. Accordingly, a simplified analysis procedure is developed by adopting a trilinear load–deflection response. The effectiveness of the simplified procedure is demonstrated by comparing its results to those of the analytical solution and the experimental values.
Get full access to this article
View all available purchase options and get full access to this article.
References
American Concrete Institute (ACI). (1999). “Building code requirements for reinforced concrete.” ACI 318-99, Farmington Hills, Mich.
American Concrete Institute (ACI). (2002). “Guide for the design and construction of externally-bonded FRP systems for strengthening concrete structures.” 440.2R-02, Farmington Hills, Mich.
An, W., Saadatmanesh, H., and Ehsani, M.(1991). “RC beams strengthened with FRP plates. II: Analysis and parametric study.” J. Struct. Eng., 117(11), 3434–3455.
Arduini, M., Tommaso, A., and Nanni, A.(1997). “Brittle failure in FRP plate and sheet bonded beams.” ACI Struct. J., 94(4), 363–370.
Blais, C., and Picard, A. (1994). “Flexural strengthening of reinforced concrete beams with composite plates.” Developments in Short and Medium Span Bridge Engineering Conf., Quéec, 919–929.
Chajes, M. J., Thomson, T. A., Jr., Januszka, T. F., and Finch, W. W., Jr.(1994). “Flexural strengthening of concrete beams using externally bonded composite materials.” J. Construction Building Materials, 8(3), 191–201.
El-Mihilmy, M. T., and Tedesco, J.(2000a). “Analysis of reinforced concrete beams strengthened with FRP laminates.” J. Struct. Eng., 126(6), 684–691.
El-Mihilmy, M. T., and Tedesco, J.(2000b). “Deflection of reinforced concrete beams strengthened with fiber-reinforced polymer (FRP) plates.” ACI Struct. J., 97(5), 679–688.
El-Mihilmy, M., and Tedesco, J.(2001). “Prediction of Anchorage failure for reinforced concrete beams strengthened with fiber-reinforced polymer plates.” ACI Struct. J., 98(3), 301–314.
Intelligent Sensing for Innovative Structures (ISIS). (2001). “Strengthening reinforced concrete structures with externally–bonded fiber reinforced polymers.” Canada design manual, Canadian Network of Centers of Excellence on Intelligent Sensing for Innovative Structures, Winnipeg, Manitoba, Canada.
Malek, A., Saadatmanesh, H., and Ehsani, M.(1998). “Prediction of failure load of R/C beams strengthened with FRP plates due to stress concentration at the plate end.” ACI Struct. J., 95(2), 142–152.
Park, R., and Paulay, T. (1975). Reinforced concrete structure, Wiley, New York.
Quantrill, R. J., Hollaway, L. C., and Thorne, A. M.(1996). “Predictions of the maximum plate end stresses of FRP strengthened beams: Part II.” Mag. Concrete Res., 48(177), 343–351.
Ritchie, P., Thomas, D., Le-Wu, L., and Connelly, M.(1991). “External reinforcement of concrete beams using fiber reinforced plastics.” ACI Struct. Eng.,88(4), 490–500.
Roberts, T. M.(1989). “Approximate analysis of shear and normal stress concentrations in the adhesive layer of plated RC beams.” Struct. Eng., 67(12), 228–233.
Ross, A., Jerome, M., Tedesco, W., and Hughes, L.(1999). “Strengthened of reinforced concrete beams with externally bonded composite laminates.” ACI Struct. J., 96(2), 212–220.
Saadatmanesh, H., and Ehsani, M.(1991). “RC beams strengthened with GFRP plates. I: Experimental study.” J. Struct. Eng., 117(11), 3417–3433.
Spadea, G., Bencardino, F., and Swamy, R. N.(1998). “Structural behavior of composite RC beams with externally bonded CFRP.” J. Compos. Constr., 2(3), 132–137.
Täljsten, B.(1997). “Strengthening of beams by plate bonding.” J. Mater. Civ. Eng., 9(4), 206–212.
Triantafillou, T. C., and Plevris, N. (1991). “Post-strengthening of R/C beams with epoxy-bonded fiber composite materials.” Proc., Specialty Conf. Advanced Composite Materials in Civil Engineering Structures, ASCE, New York, 245–256.
Ziraba, Y., Baluch, M., Basunbul, I., and Sharif, A.(1994). “Guidelines toward the design of reinforced concrete beams with external plates.” ACI Struct. J., 91(6), 639–646.
Information & Authors
Information
Published In
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Accepted: Jul 9, 2003
Published online: Jun 15, 2004
Published in print: Jul 2004
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.