Brittle Failure and Bond Development Length of CFRP-Concrete Beams
Publication: Journal of Composites for Construction
Volume 5, Issue 1
Abstract
The performance of a series of 1.5 m-long reinforced concrete beams with CFRP plates bonded to the soffit is presented. Effects of the plate length, the reinforcing steel ratio, and the thickness of the concrete cover on behavior of the beams are discussed with particular emphasis on the brittle failure mode of the concrete ripping. It was found that before the brittle failure, the composite action of the beam could be divided into three distinct zones based on the distribution of the strains along the CFRP plate: (1) The “destressed” zone, (2) the “bond development” zone; and (3) the “fully composite” zone. Concrete ripping may be prevented by limiting the strain at the transition point of the composite zone of the plate. An analytical formulation to predict the failure load corresponding to the concrete ripping failure mode is proposed based on composite theory in combination with a strain limiting criterion. The strain limit can be determined based on simple bond tests with various bond lengths for a given CFRP and adhesive combination.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
An, W., Saadatmanesh, H., and Ehsani, M. R. (1991). “RC beams strengthened with FRP plates. II: Analysis and parametric study.”J. Struct. Engrg., ASCE, 117(11), 3434–3455.
2.
Attard, M. M. ( 1995). “Buckling of reinforced concrete walls.” Civ. Engrg. Trans., Canberra, Australia, CE37(4), 271–278.
3.
Baluch, M. H., Ziraba, Y. N., Azad, A. K., Sharif, A. M., Al-Sulaimani, G. J., and Basunbul, I. A. ( 1995). “Shear strength of plated RC beams.” Mag. of Concrete Res., 47(153), 369–374.
4.
Buyukozturk, O., and Hearing, B. (1998). “Failure behavior of precracked concrete beams retrofitted with FRP.”J. Compos. for Constr., ASCE, 2(3), 138–144.
5.
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.
6.
Chajes, M. J., Finch, W. W., Jr. Janusaka, T. F., and Thomson, T. A., Jr. ( 1996). “Bond and force transfer of composite material plates bonded to concrete.” ACI Struct. J., 93(2), 208–217.
7.
Jones, R., Swamy, R. N., and Charif, A. ( 1988). “Plate separation and anchorage of reinforced concrete beams strengthened by epoxy-bonded steel plates.” The Struct. Engr., London, 66(5), 85–94.
8.
Malek, A. 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(1), 1–11.
9.
Meier, U. ( 1992). “Carbon fiber-reinforced polymers: Modern materials in bridge engineering.” Struct. Engrg. Int., Zurich, 1, 7–92.
10.
Meier, U. ( 1995). “Strengthening of structures using carbon fibre/epoxy composites.” Constr. and Build. Mat., Oxford, U.K., 9(6), 341–351.
11.
Quantrill, R. J., Hollaway, L. C., and Thorne, A. M. ( 1996). “Prediction of the maximum plate end stresses of FRP strengthened beams: Part II.” Mag. of Concrete Res., 48(117), 343–351.
12.
Raoof, M., and Zhang, S. ( 1996). “Analysis of plate peeling failure of RC beams with externally bonded plates.” Int. Conf. on Con. Repr., Rehab., and Protc., E & FN Spon, London, 605–614.
13.
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.
14.
Roberts, T. M. ( 1989). “Approximate analysis of sher and normal stress concentrations in the adhesive layer of plated RC beams.” The Struct. Engr., London, 67(12), 229–233.
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.
Sharif, A. M., 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.
17.
Vichit-Vadakan, W. ( 1997). “Shear behavior of pre-cracked, reinforced concrete beams retrofitted with glass fiber reinforced plastic sheet.” MSc thesis, Massachusetts Institute of Technology (MIT), Cambridge, Mass.
Information & Authors
Information
Published In
History
Received: Jul 14, 1999
Published online: Feb 1, 2001
Published in print: Feb 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.