Confined Columns under Eccentric Loading
Publication: Journal of Structural Engineering
Volume 121, Issue 11
Abstract
The characteristics of confined-concrete columns under strain gradient were examined. Twelve columns were tested under two different levels of end eccentricity. The test parameters included the arrangement, spacing, and volumetric ratio of confinement reinforcement. Columns with well-distributed longitudinal reinforcement, laterally supported by closely spaced transverse reinforcement, showed extremely ductile behavior, developing inelastic displacements exceeding 4% of the drift ratio without a significant loss of strength. Those with a low volumetric ratio and wide spacing of transverse steel developed strength decay immediately after the peak load. A confined concrete model, developed on the basis of column tests under concentric loading, was used to compute analytical moment-curvature relationships of the critical column section. The analytical relationships are compared with those recorded experimentally, for columns with different eccentricity of loading and parameters of confinement. The comparisons indicate that the flexural behavior of confined-concrete columns can be computed reasonably accurately by a confined-concrete model developed for concentric loading, provided that the relevant parameters of confinement are incorporated in the model, and that strain hardening in reinforcement is considered.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 121 • Issue 11 • November 1995
Pages: 1547 - 1556
Copyright
Copyright © 1995 American Society of Civil Engineers.
History
Published online: Nov 1, 1995
Published in print: Nov 1995
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