Response of RC Beams Strengthened with CFRP Laminates and Subjected to a High Rate of Loading
Publication: Journal of Composites for Construction
Volume 5, Issue 3
Abstract
Results are presented of an experimental program undertaken to investigate the effects of strain rate on the behavior of reinforced concrete (RC) beams strengthened with carbon fiber-reinforced polymer (CFRP) laminates. Nine 3-m RC concrete beams, one unstrengthened, four strengthened with S-type CFRP laminates, and four strengthened with R-type laminates, were loaded under four different loading schedules. The stroke rates ranged from 0.0167 mm/s (slow rate of loading) to 36 mm/s (fast rate of loading). This induced a strain rate in the CFRP of 2.96 με/s (slow rate) to 6,930 με/s (fast rate). Some beams were subjected to either 1 or 12 cycles of loading prior to a fast rate of loading to failure. The rapidly loaded beams showed an increase of approximately 5% in capacity, stiffness, and energy absorption. Ductility and the mode of failure were not directly affected by the change in loading rate. Precycled beams performed similarly to the beams loaded monotonically to failure but showed a 10% increase in service stiffness and a 10% loss in energy absorption. A finite-element, layered analysis is presented to predict the moment-curvature response of CFRP strengthened RC beams. The model includes the effects of strain rate and correlates well with the experimental data.
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References
1.
Canadian Standards Association (CSA). ( 1994). “Design of concrete structures.” A23.4-94, Rexdale, Ont., Canada.
2.
Erki, M. A., and Meier, U. (1999). “Impact loading of concrete beams externally strengthened with CFRP laminates.”J. Compos. for Constr., ASCE, 3(3), 117–124.
3.
Ger, G. S., Chen, J. C., Chen, W. Y., and Hsu, S. E. ( 1993). “Dynamic tensile properties of carbon/Kevlar hybrid composites.” Proc., 38th Int. SAMPE Symp., Vol. 38(2), May, 1138–1151.
4.
Heffernan, P. J. ( 1997). “Fatigue behavior of reinforced concrete beams strengthened with CFRP laminates.” PhD thesis, Royal Military College of Canada, Kingston, Ont., Canada.
5.
Kulkarni, S. M., and Shah, S. P. ( 1998). “Response of reinforced concrete beams at high strain rates.” ACI Struct. J., 95(6), 705–715.
6.
Meier, U., Deuring, M., Meier, H., and Schwegler, G. ( 1993). “Strengthening of structures with advanced composites.” Alternative materials for the reinforcement and prestressing of concrete, Chapman & Hall, New York, 153–171.
7.
Soroushian, P., and Choi, K. (1987). “Steel mechanical properties at different strain rates.”J. Struct. Engrg., ASCE, 113(4), 663–672.
8.
Soroushian, P., Choi, K., and Alhamad, A. ( 1986). “Dynamic constitutive behavior of concrete.” ACI Struct. J., 83(2), 251–258.
9.
White, T. ( 1999). “Effect of strain rate on behavior of reinforced concrete beams strengthened with carbon fibre reinforced polymer laminates.” MS thesis, University of Waterloo, Waterloo, Ont., Canada.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 5 • Issue 3 • August 2001
Pages: 153 - 162
History
Received: Oct 18, 1999
Published online: Aug 1, 2001
Published in print: Aug 2001
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