Straight, Single‐Tapered Composite I‐Beams of Orthotropic Materials
Publication: Journal of Materials in Civil Engineering
Volume 4, Issue 4
Abstract
Design methods for tapered members of multiple materials with nonrectangular cross sections are not available. This finite‐element study of straight, single‐tapered I‐beams was conducted to aid in developing a rational design method for nonprismatic, I‐shaped structural members of layered orthotropic materials. Particular emphasis is placed on wood composites. Taper geometry is considered in concert with the elastic constants of the web substrate. Comparisons of the stresses and deflections in a prismatic beam and a tapered beam of the same average depth and having the same elastic properties for the web are used to identify potential design considerations. The bending, vertical, and shear stress maximums are greater in the tapered beam than in the prismatic beam. In addition, the stresses are distributed differently if the beam is tapered rather than prismatic. For example, the maximum shear stress is not necessarily in the web. Deflection of the tapered member is 19% greater and occurs at 0.43L rather than at midspan.
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Information & Authors
Information
Published In
Journal of Materials in Civil Engineering
Volume 4 • Issue 4 • November 1992
Pages: 399 - 414
Copyright
Copyright © 1992 ASCE.
History
Published online: Nov 1, 1992
Published in print: Nov 1992
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