Fracture Model for Flexural Failure of Beams Retrofitted with CARDIFRC
Publication: Journal of Engineering Mechanics
Volume 129, Issue 9
Abstract
A new retrofitting technique based on a material [Cardiff Fiber Reinforced Concrete (CARDIFRC)] compatible with concrete has been developed at Cardiff University. It overcomes some of the problems associated with the current techniques based on externally bonded steel plates and fiber-reinforced plastic laminates which are due to the mismatch of their tensile strength and stiffness with that of the concrete structure being retrofitted. CARDIFRC is characterized by high tensile/flexural strength and high energy-absorption capacity (i.e., ductility). The special characteristics of CARDIFRC make it particularly suitable for repair, remedial and upgrading activities (i.e., retrofitting) of existing concrete structures. It has been shown that damaged reinforced concrete beams can be successfully strengthened and rehabilitated in a variety of different retrofit configurations using precast CARDIFRC strips adhesively bonded to the prepared surfaces of the damaged beams. To predict the moment resistance of the beams retrofitted in this manner an analytical model is introduced in the present paper. This model takes a fracture mechanics approach and follows the initiation and growth of the flexural crack that eventually leads to the failure of the retrofitted beams. The results of this analytical model are found to be in very good agreement with the test results.
Get full access to this article
View all available purchase options and get full access to this article.
References
ACI Committee 446. (1992). “Fracture mechanics: Application to concretestructures and implications with regard to the code.” Rep. 446-2R, ACI, Detroit.
Ahmed, O., and Gemert, D. V. (1999). “Behaviour of R.C. beams strengthened in bending by CFRP laminates.” Proc., Structural Faults and Repair—99: 8th Int. Conf., London (CD-ROM).
Alaee, F. J., Benson, S. D. P., and Karihaloo, B. L. (2001). “Strengthening of RC beams with high-performance cementitious composites.” Proc., Int. Conf. on Civil Engineering, Technical Committee ICCE-2001, eds., Interline, Bangalore, India, 1–13.
Alaee, F. J., Benson, S. D. P., and Karihaloo, B. L.(2002). “High-performance cementitious composites for retrofitting.” Int. J. Mater. Prod. Technol., 17(1/2), 17–31.
Alaee, F. J., and Karihaloo, B. L. (2003). “Retrofitting of RC beams with CARDIFRC.” J. Compos. Constr., 7(3).
Barenblatt, G. I.(1959). “On equilibrium cracks forming during brittle fracture.” Prikl. Mat. I Mekh., 23, 434–444 (in Russian).
Bosco, C., and Carpinteri, A. (1992). “Fracture mechanics evaluation of minimum reinforcement in concrete structures.” Application of fracture mechanics to reinforced concrete, Proc., Int. Workshop, Turin, Italy, 1990, A. Carpinteri, ed., Elsevier, London, 347–377.
Büyüköztürk, O., and Hearing, B.(1998). “Failure behavior of precracked concrete beams retrofitted with FRP.” J. Compos. Constr., 2(3), 138–144.
CEB-FIP Model Code. (1993). Lausanne, Switzerland.
El-Refaie, S. A., Ashour, A. F., and Garrity, S. W. (1999). “Flexural capacity of R.C. beams strengthened with external plates.” Proc., Structural Faults and Repair—99: 8th Int. Conf., London (CD-ROM).
Fanning, P., and Kelly, O. (1999). “Shear strengthening of R.C. beams: An experimental study using CFRP plates.” Proc., Structural Faults and Repair–99: 8th Int. Conf., London (CD-ROM).
Guinea, G. V., Pastor, J. Y., Planas, J., and Elices, M.(1998). “Stress intensity factor, compliance and CMOD for a general three-point-bend beam.” Int. J. Fract., 89, 103–116.
Hussain, M., Sharif, A., Basenbul, I. A., Baluch, M. H., and Al-Sulaimani, G. J.(1995). “Flexural behaviour of precracked reinforced concrete beams strengthened externally by steel plates.” ACI Struct. J., 92(1), 14–22.
Jones, R., Swamy, R. N., and Charif, A.(1988). “Plate separation and anchorage of reinforced concrete beams strengthened by epoxy-bonded steel plates.” Struct. Eng., 66(5), 85–94.
Kaar, P. H., and Mattock, A. H.(1963). “High strength bar as concrete reinforcement, Part 4. Control of cracking.” J. PCA Res. Dev. Lab., 7(1), 15–38.
Karihaloo, B. L., Alaee, F. J., and Benson, S. D. P. (2002). “A new technique for retrofitting damaged concrete structures.” Proc., Institution of Civil Engineers., Buildings and Structures, 152(4), 309–318.
Karihaloo, B. L., Benson, S. D. P., Didiuk, P. M., Fraser, S. A., Hamill, N., and Jenkins, T. A. (2000). “Retrofitting damaged RC beams with high-performance fibre-reinforced concrete.” Proc., Concrete Communication Conf., British Cement Association, Birmingham, 153–164.
Lange-Kornbak, D., and Karihaloo, B. L. (1999). “Fracture mechanical prediction of transitional failure and strength of singly-reinforced beams.” Minimum reinforcement in concrete members, ESIS Publication 24, A. Carpinteri, ed., Elsevier, London, 31–42.
Leung, C. K. Y. (1998). “Delamination failure in concrete beams retrofitted with a bonded plate.” Fracture mechanics of concrete structures, H. Mihashi, and K. Rokugo, eds., Vol. 3, AEDIFICATIO, Freiburg, Germany, 1783–1792.
Nanni, A.(1995). “Concrete repair with externally bonded FRP reinforcement: examples from Japan.” Concr. Int., 97, 22–26.
Ohgishi, S., Ono, H., Takatsu, M., and Tanahashi, I. (1986). “Influence of test conditions on fracture toughness of cement paste and mortar.” In Fracture toughness and fracture energy of concrete, Proc., Int. Conf., Lausanne, Switzerland, 1985, F. H. Wittmann, ed., Elsevier, Amsterdam, 281–290.
Tada, H., Paris, P., and Irwin, G. (1985). The stress analysis of cracks handbook, Del Research Corporation, St. Louis, Part 2, 16–17.
Yagi, K., Tanka, K., and Otaguro, H. (1999). “Durability of carbon fibre sheet for repair and retrofitting.” Proc., Structural Faults and Repair–99: 8th Int. Conf., London (CD-ROM).
Ziraba, N., Baluch, M. H., Basunbul, I. A., Sharif, A., Azad, A. K., and Al-Sulaimani, G. J.(1994). “Guidelines toward the design of RC beams with external plates.” ACI Struct. J., 91(6), 639–646.
Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 129 • Issue 9 • September 2003
Pages: 1028 - 1038
Copyright
Copyright © 2003 American Society of Civil Engineers.
History
Received: Aug 6, 2002
Accepted: Jan 16, 2003
Published online: Aug 15, 2003
Published in print: Sep 2003
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.