Effect of Transverse Reinforcement on the Behavior of Tension Lap splice in High-Strength Reinforced Concrete Beams

Authors: Ahmed H. Abdel-Kareem, Hala. Abousafa, Omia S. El-Hadidi

Abstract:

The results of an experimental program conducted on seventeen simply supported concrete beams to study the effect of transverse reinforcement on the behavior of lap splice of steel reinforcement in tension zones in high strength concrete beams, are presented. The parameters included in the experimental program were the concrete compressive strength, the lap splice length, the amount of transverse reinforcement provided within the splice region, and the shape of transverse reinforcement around spliced bars. The experimental results showed that the displacement ductility increased and the mode of failure changed from splitting bond failure to flexural failure when the amount of transverse reinforcement in splice region increased, and the compressive strength increased up to 100 MPa. The presence of transverse reinforcement around spliced bars had pronounced effect on increasing the ultimate load, the ultimate deflection, and the displacement ductility. The prediction of maximum steel stresses for spliced bars using ACI 318-05 building code was compared with the experimental results. The comparison showed that the effect of transverse reinforcement around spliced bars has to be considered into the design equations for lap splice length in high strength concrete beams.

Keywords: Ductility, high strength concrete, tension lap splice, transverse reinforcement, steel stresses.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1336122

References:

[1] ACI 318-05, "Building Code Requirements for Structural concrete and commentary,” American Concrete Institute, Farmington Hills, Mich, 2005.
[2] Diab, A. M., "Lap Splices in Reinforced Concrete Beams Subjected to Bending,” Master thesis, University of Alexandria, Egypt, 2008.
[3] Esfahani, M. R., Rangan, B.V., "Bond between Normal Strength and High- Strength Concrete (HSC) and Reinforcing Bars in Splices in Beams,” ACI Structural Journal, V. 95, No. 3, May-June 1998, pp. 272-280.
[4] Azizinamini, A., Darwin, D., Eligehausen, R., Pavel, P., Ghosh, S. K., " Proposed Modifications to ACI 318-95 Tension Development and Lap Splice for High- Strength Concrete,” ACI Structural Journal, V. 96, No. 6, Nov.-Dec. 1999, pp. 922-926.
[5] Zuo, j., Dawin, D.," Splice Strength of Conventional and High Relative Rib Area Bars in Normal and High- Strength Concrete,” ACI Structural Journal, V. 97, No. 4, July-August 2000, pp. 630-641.
[6] Hamad, B. S., Najjar, S., "Evaluation of the Role of Transverse Reinforcement in Confining Tension Lap Splices in High Strength Concrete,” Materials and Structures, V. 35, May 2002, pp. 219-228.
[7] Turk, K., Yildirim, M. S., "Bond Strength of Reinforcement in Splices in Beams,” Structural Engineering and Mechanics, V. 16, 2002, No. 4.
[8] ACI Committee 408, "Bond and Development of Straight Reinforcing Bars in Tension,” ACI 408R-03, American Concrete Institute, Farmington Hills, Mich, 2003.
[9] Azizinamini, A., Stark, M., Roller, J. H. and Ghosh, S. K., "Bond Performance of Reinforcing Bars Embedded in High-Strength Concrete,” ACI Structural Journal, V.90, No.5, Sept.-Oct. 1993, pp. 554-561.
[10] Azizinamini, A., Chisala, M., Roller, J. H., and Ghosh, S. K., "Tension Development Length of Reinforcing Bars Embedded in High-Strength Concrete,” Engineering Structures, V. 17, No. 7, 1995, pp. 512-522.
[11] Park, R., Ruitong, D., "Ductility of Doubly Reinforced Concrete Beam Sections,” ACI Structural Journal, V.85, No.3, March-April 1998, pp. 217-225.