Shear Strength of Prestressed Concrete T-Beams with Steel Fibers Over Partial/Full Depth

ACI Structural Journal, May/Jun 2006 by Thomas, Job, Ramaswamy, Ananth

h, h^sub f^ = height of beam and flange

M^sub 0^, M^sub 0^' = moment necessary to produce zero stress in concrete at extreme fiber and at d

RI = fiber reinforcing index (= V^sub f^ L^sub f^/φ^sub f^)

s^sub v^ = spacing of stirrups

V^sub a^ = shear-resisting force offered by aggregate interlocking mechanism

V^sub c^ = shear-resisting force offered by uncracked concrete

V^sub D^ = shear resistance offered by dowel action of reinforcement

V^sub F^, v^sub F^ = shear resistance and shear stress offered by fiber pullout mechanisms

V^sub f^ = volume fraction of fiber with respect to volume of concrete

V^sub i^ = shear occurring at the section of Mmax

V^sub p^ = vertical component of effective prestressing force (equal to zero for straight prestressed bars)

V^sub u^ = shear resistance of reinforced concrete beam

V^sub uc^, v^sub uc^ = shear resistance and shear stress offered by concrete section

V^sub ucF^, v^sub ucF^ = shear resistance and shear stress offered by fiber-reinforced concrete section

V^sub uo^, v^sub uo^ = shear resistance and shear stress observed in experiment

V^sub us^ = shear-resisting force offered by steel stirrups

v^sub upi^ = predicted shear strength of beam (including stirrup contribution) by various methods (for example, i-th)

φ^sub f^, L^sub f^ = diameter and length of fiber

η^sub bF^, τ^sub bF^ = bond efficiency factor and bond shear strength, depending on fiber type

ρ^sub s^, ρ^sub v^ = longitudinal tensile and vertical reinforcement ratio (= ([A^sub s^ A^sub ps^]/[b^sub w^d] and A^sub v^/[b^sub w^s^sub v^])

ψ^sub pF^ = partial depth fiber parameter

Σ = size effect factor

REFERENCES

1. Swamy, R. N., and Bahia, H. M.,"Influence of Fiber Reinforcement on the Dowel Resistance to Shear," ACI JOURNAL, Proceedings V. 76, No. 2, Feb. 1979, pp. 327-355.

2. Lim, D. H., and Oh, B. H., "Experimental and Theoretical Investigation on the Shear of Steel Fiber Reinforced Concrete Beams," Engineering Structures, V. 21, No. 10, 1999, pp. 937-944.

3. ACI Committee 318, "Building Code Requirements for Structural Concrete (ACI 318-02) and Commentary (318R-02)," American Concrete Institute, Farmington Hills, Mich., 2002, 443 pp.

4. BS 8110, "Structural Use of Concrete Part 1-Code of Practice for Design and Construction," British Standard Institutions, London, 1997.

5. IS 1343, "Code of Practices for Prestressed Concrete," Bureau of Indian Standards, New Delhi, India, 1980, 62 pp.

6. Padmarajaiah, S. K., and Ramaswamy, A., "Behavior of Fiber-Reinforced Prestressed and Reinforced High-Strength Concrete Beams Subjected to Shear," ACI Structural Journal, V. 98, No. 5, Sept.-Oct. 2001, pp. 752-761.

7. Padmarajaiah, S. K., and Ramaswamy, A., "A Beam and Arch Action Model for Computing the Shear Strength of Prestressed and Reinforced HSFRC Beams," Journal of Structural Engineering, SERC-India, V. 28, No. 1, 2001, pp. 7-15.

8. Abdul-Wahab, H. M. S., and Al-Kadhimi, S. G., "Effect of SFRC on Shear Strength of Prestressed Concrete Beams," Magazine of Concrete Research, V. 52, No. 1, 2000, pp. 43-51.