TECHNICAL PAPERS
Jun 1, 1986

Effectiveness Factor for Shear in Concrete Beams

Publication: Journal of Structural Engineering
Volume 112, Issue 6

Abstract

A study to determine the parameters affecting web crushing failures in thin‐webbed concrete beams is summarized. Such failures are characterized by the crushing of the concrete. The average compressive stress in the web at crushing is usually lower than the concrete cylinder strength, and is defined as a function of that strength, using an effectiveness factor that has not so far been satisfactorily quantified. By means of an extensive statistical study of published test data, the primary variables affecting effectiveness factor are isolated and used to develop a model, which is proposed for evaluation of the effectiveness factor. The most significant variables are shown to be the web width/depth ratio and the shear span/depth ratio. This finding confirms some empirical results from past studies, but does not support the common practice of defining web effectiveness factor in terms of concrete cylinder strength as the only variable.

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References

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2.
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3.
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4.
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Go to Journal of Structural Engineering
Journal of Structural Engineering
Volume 112Issue 6June 1986
Pages: 1464 - 1477

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Published online: Jun 1, 1986
Published in print: Jun 1986

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Authors

Affiliations

Barrington de V. Batchelor, M. ASCE
Prof., Dept. of Civ. Engrg., Queens Univ., Kingston, ON, Canada, K7L 3N6
Herbert K. George
Engr. Careng Group, 5 Sydney St., Port‐of‐Spain, Trinidad, W. Indies
T. Ivan Campbell
Prof., Dept. of Civ. Engrg., Queens Univ., Kingston, ON, Canada K7L 3N6

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