Shear Flow Zone in Torsion of Reinforced Concrete
Publication: Journal of Structural Engineering
Volume 116, Issue 11
Abstract
Rausch's classical formula overestimates the torsional strength of reinforced concrete members to an unacceptable degree. The error is traced to the incorrect determination of the centerline of the circulating shear flow. The position of the centerline of shear flow is directly related to the thickness of the shear flow zone The determination of in torsion is analogous to the determination of the depth of the compression zone in bending. This paper presents a simple theoretical method to calculate based on the softened truss model theory. The method utilizes the equilibrium and compatibility conditions, as well as a softened stress‐strain relationship for concrete struts. Since is calculated by a rigorous procedure, an accurate torsional strength can be predicted. The prediction of the torsional strengths of 61 beams found in the literature compares extremely well with the test values. In addition, a very simple formula for is also proposed for the practical design of members subjected to torsion.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 116 • Issue 11 • November 1990
Pages: 3206 - 3226
Copyright
Copyright © 1990 ASCE.
History
Published online: Nov 1, 1990
Published in print: Nov 1990
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