Tension Lap Splices Strengthened with Ultrahigh-Performance Fiber-Reinforced Concrete
Publication: Journal of Materials in Civil Engineering
Volume 27, Issue 7
Abstract
This paper presents the results of an experimental program undertaken for evaluating the effectiveness of ultrahigh performance fiber-reinforced concrete (UHPFRC) for strengthening deficient tension lap splices. A total of 18 full-scale beam specimens were tested. Tension reinforcement consisted of two deformed bars spliced at midspan. The strengthening technique consists of replacing normal concrete in the splice region with UHPFRC. One type of fiber concrete was used in this experimental program. It is characterized by a compressive strength of 130 MPa, a high tensile strength of 10 MPa, and ductile strain hardening characteristics in direct tension. The parameters considered were: splice length, bar diameter, repair depth, and bar relative position. To isolate the contribution of UHPFRC, no stirrups were used. The results clearly show the effectiveness of UHPFRC for strengthening deficient lap splices. Failure by splitting in the lap splice region was completely eliminated due to the high tensile strength and energy absorption capabilities of the UHPFRC used. Bond stresses that were more than twice those of normal concrete were observed. The UHPFRC ductility allows for the development of quasi-plastic tensile stresses around the reinforcing bars to resist the splitting forces. For the selected UHPFRC, this stress was evaluated at approximately 7.3 MPa, which is applicable to tensile strains of up to 0.2% before the formation of discrete cracks. Although the paper focuses on rehabilitation, the results are also applicable to new constructions. Suggestions for further research and better classification of UHPFRC for structural applications are identified.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The research project was financially supported by the Quebec Ministry of Transportation and the Natural Science and Engineering Research Council of Canada (NSERC), through the Canadian Seismic Research Network (CSRN) and the Discovery Grant programs. Some materials were graciously provided by Bekaert and Euclid. The authors would like to express their gratitude to the technical personnel of École Polytechnique de Montréal Hydro-Québec Structures Laboratory.
References
Braike, S. (2007). “Design of precast bridge elements made with high and ultrahigh-performance fiber reinforced concrete.” M.Sc. thesis, Polytechnique Montreal, QC, Canada (in French).
Cairns, J., and Abdullah, R. B. (1996). “Bond strength of black and epoxy-coated reinforcement—A theoretical approach.” ACI Mater. J., 93(4), 362–369.
Canbay, E., and Frosch, R. J. (2005). “Bond strength of lap-spliced bars.” ACI Struct. J., 102(4), 605–614.
Chamberlin, S. J. (1952). “Spacing of spliced bars in tension pull-out specimens.” J. Am. Concr. Inst., 24(4), 261–274.
Chinn, J., Ferguson, P. M., and Thompson, J. N. (1955). “Lapped splices in reinforced concrete beams.” J. Am. Concr. Inst., 27(2), 201–213.
Darwin, D. (2005). “Tension development length and lap splice design for reinforced concrete members.” Prog. Struct. Eng. Mater., 7(4), 210–225.
Habel, K., Charron, J.-P., Braike, S., Douglas Hooton, R., Gauvreau, P., and Massicotte, B. (2008). “Ultra-high performance fibre reinforced concrete mix design in central Canada.” Can. J. Civ. Eng., 35(2), 217–224.
Harajli, M., Hamad, B., and Karam, K. (2002). “Bond-slip response of reinforcing bars embedded in plain and fiber concrete.” J. Mater. Civ. Eng., 14(6), 503–511.
Harajli, M. H. (2010). “Bond behavior in steel fiber-reinforced concrete zones under static and cyclic loading: Experimental evaluations and analytical modeling.” J. Mater. Civ. Eng., 22(7), 674–686.
Lagier, F., Massicotte, B., and Charron, J.-P. (2012). “Bond splitting strength of lap splice embedded in ultra high performance fibre reinforced concrete under direct tension.” Bond in Concrete 2012, J. W. Cairns, G. Metelli, and G. A. Plizzari, eds., Brescia, Italy, 351–358.
Massicotte, B., and Boucher-Proulx, G. (2008). “Seismic retrofitting of rectangular bridge piers with UHPFRC jackets.” 7th RILEM Symp. on Fibre-Reinforced Concrete, PRO 60, France, 969–975.
Mazumder, M. H., Gilbert, R. I., and Chang, Z. T. (2012). “A reassessment of the analysis provisions for bond and anchorage length of deformed reinforcing bars in tension.” Bonfring Int. J. Ind. Eng. Manage. Sci., 2(4), 1–8.
Parra-Montesinos, G. J. (2005). “High-performance fiber-reinforced cement composites: An alternative for seismic design of structures.” ACI Struct. J., 102(5), 668–675.
Priestley, M. J. N., Seible, F., and Calvi, G. M. (1996). Seismic design and retrofit of bridges, Wiley, New York.
Thompson, M. K., Jirsa, J. O., Breen, J. E., and Klingner, R. E. (2002). “Anchorage behavior of headed reinforcement: Literature review.”, Texas Dept. of Transportation, Austin, TX.
Vachon, D., and Massicotte, B. (2004). “Seismic retrofitting of rectangular bridge piers with FRC jackets.” Proc., 6th RILEM Symp. on Fibre-Reinforced Concrete, PRO 39, France, 1247–1256.
Zuo, J., and Darwin, D. (2000). “Splice strength of conventional and high relative rib area bars in normal and high-strength concrete.” ACI Struct. J., 97(4), 630–641.
Information & Authors
Information
Published In
Journal of Materials in Civil Engineering
Volume 27 • Issue 7 • July 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Oct 1, 2013
Accepted: Jul 28, 2014
Published online: Sep 5, 2014
Discussion open until: Feb 5, 2015
Published in print: Jul 1, 2015
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.