Evaluation of Bond Strength between Steel Fiber Reinforced Ultra-High Strength Concrete and Rebar

Abstract:

In order to design reinforced concrete member using steel fiber ultra high strength concrete, current structural design methods should be re-evaluated because it has significant difference in material characteristics compared with normal concrete. In this study, bond strength of steel fiber reinforced ultra-high strength concrete was evaluated. For this purpose, direct pull out test specimens were constructed with variables of cover thickness, compressive strength of matrix and fiber inclusion ratio. According to the test, bond strength were sensitively varied with cover thickness and fiber inclusion. Because bond strength was determined by tensile strength of concrete. Comparing test results with theoretical methods suggested by Tepfers, specimens without steel fiber show good agreement with analytical method, because this method were based on elasticity. And other empirical equations were evaluated with other previous researches.

• Periodical: Key Engineering Materials (Volume 665)
• Pages: 41-44
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.665.41
• Online since: September 2015
• Authors: B.I. Bae*, Hyun Ki Choi, Chang Sik Choi
• Keywords: Bond Stress, Compressive Strength of Concrete, Cover Thickness, Steel Fiber Reinforced Reactive Powder Concrete (Sf-RPC), Steel Fiber Volume Fraction

References

[1] Ralejs Tepfers, Cracking of concrete cover along anchored deformed reinforcing bars. Magazine of concrete research. Vol 31, Issue 106, pp.3-12 (1979).

DOI: 10.1680/macr.1979.31.106.3

[2] Eligehausen, Rolf, Popov, Egor P., Bertero, Vitelmo V., Local bond stress-slip relationships of deformed bars under generalized excitations, UCB/EERC-83/23, Earthquake Engineering Research Center, University of California, Berkeley, 1983-10, pp.1-169 (1983).

[3] Esfahani, M. R. and Rangan, B. V., Bond between normal strength and high strength concrete(HSC) and reinforcing bars in splices in beams, ACI Structural Journal, vol. 93, No. 3, pp.272-280 (1998).

DOI: 10.14359/545

[4] Huang, Z. & Engström, B. & Magnusson, J., Experimental investigation of the bond and anchorage behaviour of deformed bars in high strength concrete. Report 94: 4, Chalmers University of Technology, Chalmers (1996).

[5] CEB-FIP Model Code 90, Committee Euro-international du Beton, Bulletin d'information (1990).

DOI: 10.1680/ceb-fipmc1990.35430

[6] EN 1992-1-1: 1992: Eurocode 2: Part 1. 1: General rules and rules for buildings: BSI (2005).