Strength of RC Cantilever Slabs Bonded with GFRP Strips
Publication: Journal of Composites for Construction
Volume 5, Issue 4
Abstract
Strengthening of RC cantilever slabs using bonded glass-fiber–reinforced plastic (GFRP) strips has recently been explored. That work led to the proposal that the GFRP strips should be anchored to the supporting wall using epoxy-mortar–filled horizontal slots and to the slab using fiber anchors, to prevent or limit debonding. This paper focuses on the strength of RC cantilever slabs strengthened using this method. Experimental work on model cantilever slabs with steel reinforcement of different amounts and different positions is presented. Because of the presence of fiber anchors, all strengthened slabs failed by tensile rupture of the fiber-reinforced plastic (FRP), although in some of the slabs partial debonding had appeared before the FRP rupture took place. Flexural strength equations based on the conventional plane section assumption are next described and shown to predict the test results well, even for slabs with partially debonded FRP strips. Finally, the effect of preloading on the strength of strengthened slabs is discussed.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Almusallam, T. H. ( 1997). “Analytical prediction of flexural behavior of concrete beams reinforced by FRP bars.” J. Compos. Mat., 31(7), 640–657.
2.
American Concrete Institute (ACI). ( 1992). “Building code requirements for reinforced concrete (revised 1992) and commentary (revised 1992).” ACI 318-89, ACI 318R-89, Detroit.
3.
An, W., Saadatmanesh, H., and Ehsani, R. (1991). “RC beams strengthened with GFRP plates II: Analysis and parametric study.”J. Struct. Engrg., ASCE, 117(11), 3434–3455.
4.
Arduini, M., and Nanni, A. ( 1997). “Parametric study of beams with externally bonded FRP reinforcement.” ACI Struct. J., 94(5), 493–501.
5.
ASTM. ( 1995). “Standard test method for tensile properties of polymer matrix composite materials.” D 3039/D 3039M-95, West Conshohocken, Pa.
6.
Buyukozturk, O., and Hearing, B. (1998). “Failure behavior of pre-cracked concrete beams retrofitted with FRP.”J. Compos. for Constr., ASCE, 2(3), 138–144.
7.
Chaallal, O., Nollet, M.-J., and Perraton, D. ( 1998). “Strengthening of reinforced concrete beams with externally bonded fiber-reinforced-plastic plates: Design guidelines for shear and flexure.” Can. J. Civ. Engrg., Ottawa, 25, 692–704.
8.
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.” Constr. and Build. Mat., 8(3), 191–201.
9.
Malek, M., Saadatmanesh, H., and Ehsani, M. R. ( 1998). “Prediction of failure load of R/C beams strengthened with FRP plate due to stress concentration at the plate end.” ACI Struct. J., 95(2), 142–152.
10.
Meier, U., and Winistorfer, A. ( 1995). “Retrofitting of structures through external bonding of CFRP sheets.” Proc., 2nd Int. RILEM Symp., Non-metallic (FRP) reinforcement for concrete struct., E & FN Spon, London, 509–516.
11.
Quantrill, R. J., Hollaway, L. C., and Thorne, A. M. ( 1996a). “Experimental and analytical investigations of FRP-strengthened beam response: Part I.” Mag. Concrete Res., 48(177), 331–342.
12.
Quantrill, R. J., Hollaway, L. C., and Thorne, A. M. ( 1996b). “Predictions of the maximum plate end stresses of FRP strengthened beams: Part II.” Mag. Concrete Res., 48(177), 343–351.
13.
Park, R., and Paulay, T. ( 1975). Reinforced concrete structures, Wiley, New York.
14.
Ritchie, P. A., Thomas, D. A., Lu, L. W., and Connelly, G. M. ( 1991). “External reinforcement of concrete beams using fiber reinforced plastics.” ACI Struct. J., 88(4), 490–500.
15.
Saadatmanesh, H., and Ehsani, M. R. (1991). “RC beams strengthened with GFRP plates I: Experimental study.”J. Struct. Engrg., ASCE, 117(11), 3417–3433.
16.
Saadatmanesh, H., and Malek, A. M. (1998). “Design guidelines for flexural strengthening of RC beams with FRP plates.”J. Compos. for Constr., ASCE, 2(4), 158–164.
17.
Sharif, A., Al-Sulaimani, G. J., Basunbul, I. A., Baluch, M. H., and Ghaleb, B. N. ( 1994). “Strengthening of initially loaded reinforced concrete beams using FRP plates.” ACI Struct. J., 91(2), 160–168.
18.
Spadea, G., Bencardino, F., and Swamy, R. N. (1998). “Structural behavior of composite beams with externally bonded CFRP.”J. Compos. for Constr., ASCE, 2(3), 132–137.
19.
Steiner, W. ( 1996). “Strengthening of structures with CFRP strips.” Proc., 2nd Int. Conf., Advanced Compos. Mat. in Bridges and Struct., M. M. Bi-Badry, 407–417.
20.
Teng, J. G., Cao, S. Y., and Lam, L. ( 2001). “Behaviour of GFRP-strengthened RC cantilever slabs.” Constr. and Build. Mat., 15(7), 339–349.
21.
Teng, J. G., Lam, L., Chan, W., and Wong, J. (2000). “Retrofitting of deficient RC cantilever slabs using GFRP strips.”J. Compos. for Constr., ASCE, 4(2), 75–84.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 5 • Issue 4 • November 2001
Pages: 221 - 227
History
Received: Dec 20, 1999
Published online: Nov 1, 2001
Published in print: Nov 2001
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.