CFRP Strengthening for Punching Shear of Interior Slab–Column Connections
Publication: Journal of Composites for Construction
Volume 10, Issue 5
Abstract
This paper presents the results of an experimental investigation studying the effect of retrofitting interior slab–column connections against punching shear failure with externally bonded carbon fiber reinforced polymer (CFRP) strips. Six full-scale, slab specimens were constructed. The effect of varying the CFRP strengthening amount and configuration on the load-carrying capacity of the slab specimens was investigated. Specimens were supported along their edges and tested to failure. Strengthened slabs showed an increase in stiffness between 29 and 60% and in punching capacity between 6 and 16% with respect to the control unstrengthened slab. An analytical model was refined to predict the punching shear capacity of the specimens strengthened with CFRP strips. The model takes into account both the configuration and amount of CFRP strips. The proposed model shows good agreement with the experimental results.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers gratefully acknowledge NSERC’s Industrial program, Halsall Associates Ltd., and Sika Canada for their support, donation and cooperation to successfully complete this research. The help of the technical staff at the Structures Laboratory of the University of Waterloo is highly appreciated.
References
ACI Committee 440 (1996). “State-of-the-art report on fiber reinforced plastic reinforcement for concrete structures.” Rep. Prepared for the American Concrete Institute, Detroit.
ACI Committee 318 (1999). Building code requirements for reinforced concrete, Detroit.
British Standards Institution (BS). (1997). “Structural use of concrete: Code of practice for design and construction.” BS 8110, Part 1, London.
Canadian Standards Association (CSA). (1994). “Design of concrete structures for buildings.” CSA A23.3, Ontario, Canada.
Chen, C. C., and Li, C. Y. (2000). “An experimental study on the punching shear behaviour of RC slabs strengthened by GFRP.” Proc., Int. Workshop on Punching Shear Capacity of RC slabs, Stockholm, Sweden, 415–422.
Ebead, U. (2002). “Strengthening of reinforced concrete two-way slab.” Ph.D. thesis, Memorial Univ. of Newfoundland, St. John’s, Newfoundland, Canada, 231.
Elstner, R. C., and Hognestad, E. (1956). “Shearing strength of reinforced concrete slabs.” J. Am. Concr. Inst., 53(2), 29–58.
Erki, M. A., and Heffernan, P. J. (1995). “Reinforced concrete slabs externally strengthened with fiber-reinforced plastic materials.” Proc., 2nd Int. Symp. on Nonmetallic (FRP) Reinforcement for Concrete Structures, L. Taerwe ed., Belgium, 509–516.
Ghali, A., Sargious, M. A., and Huizer, A. (1974). “Vertical prestressing of flat plates around columns.” Shear in Reinforced Concrete Publications SP-42, ACI, Detroit.
Harajli, M. H, and Soudki, K. A. (2003). “Shear strengthening of interior slab–column connections using fiber-reinforced polymer sheets.” J. Compos. Constr., 7(2), 145–153.
Hassanzadeh, G., and Sundqvist, H. (1998). “Strengthening of bridge slabs on columns.” No. 21, Nordic Concrete Research, Norway.
ISIS Canada (2001). “Strengthening reinforced concrete structures with externally-bonded fiber reinforced polymers (FRPs).” Design manual No. 4, Manitoba, Canada.
Malvar, L. J., Warren, G. E., and Inaba, C. M. (1996). “Large scale tests on Navy reinforced concrete pier decks strengthened with CFRP sheets.” Proc., 3rd Int. Conf. on Advanced Composite Materials in Bridges and Structures, Montréal, 497–504.
Menétrey, P., Brühwiler, E. (1997). “Punching shear strengthening of reinforced concrete: Experimental & analytical investigations.” Proc., 7th Int. Conf. on Structural Faults and Repair, Vol. 2, 451–458.
Miller, B., and Nanni, A. (1999). “Bond between carbon-fiber reinforced polymer sheets and concrete.” Proc., ASCE 5th Materials Congress, L. C. Bank, ed., ASCE, Reston, Va., 240–247.
Mowrer, R. D., and Vanderbilt, M. D. (1967). “Shear strength of lightweight aggregate reinforced concrete flat plates.” J. Am. Concr. Inst., 64(11), 722–729.
Ospina, C. E., Alexander, S. D. B., and Cheng, J. J. R. (2001). “Behaviour of concrete slabs with fibre-reinforced polymer reinforcement.” Structural Engineering Rep. No. 242, Dept. of Civil and Environmental Engineering, Univ. of Alberta, Alberta, Canada.
Tan, K. H. (2000). “Punching shear strength of RC slabs bonded with FRP systems.” Proc., 3rd Int. Conf. on Advanced Composite Materials in Bridges and Structures, Ottawa, 387–394.
Van Zowl, T., and Soudki, K. (2003). “Strengthening of concrete slab–column connections for punching shear.” Technical Rep., Univ. of Waterloo, Waterloo, Canada.
Wang, J. W., and Tan, K. I. (2001). “Punching shear behaviour of RC flat slabs externally strengthened with CFRP system.” Proc., 5th Int. Conf. on Fibre-Reinforced Plastic for Reinforced Concrete Structures (FRPRCS-5), Vol. 2, London, 997–1005.
Wight, G., Erki, M. A., Bizindavyi, L., and Green, M. F. (2003). “Prestressed CFRP sheets for strengthening two-way slabs.” Composite in Construction, Proc., International Conf. (CCC 2003), Italy.
Zhang, J. W., Teng, J. G., Wong, Y. L., and Lu, Z. T. (2001). “Behavior of two-way RC slabs externally bonded with steel plate.” J. Struct. Eng., 127(4), 390–397.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 10 • Issue 5 • October 2006
Pages: 410 - 418
Copyright
© 2006 ASCE.
History
Received: Dec 14, 2004
Accepted: Aug 19, 2005
Published online: Oct 1, 2006
Published in print: Oct 2006
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.