Design Equation for Overlap Tubular K-Joints under Axial Loading
Publication: Journal of Structural Engineering
Volume 126, Issue 7
Abstract
Using a previously presented finite-element study of axially loaded overlap tubular K-joints as a platform, this paper presents further work that aimed at extending and enhancing the strength estimation equation already presented. The current work includes extending the θ (brace angle) validity range to 30° ≤ θ ≤ 60°; investigating the effects of the yield stress/ultimate tensile strength ratio and the brace/chord yield stress ratio; exploring the influence of loading reversal; and quantifying the reduction in strength caused by the absence of the hidden weld. The end result of these studies is a new, extended capacity equation. The accuracy of the proposed equation to predict the axial capacity of test joints was established by assessing it using an experimental database. The applicability of the proposed equation for design practice was further ascertained by investigating strength sensitivities to material curve variations, different chord end support conditions, and joints with unequal brace inclinations. The proposed design equation is found to be both accurate and conservative and is therefore recommended to be used in practice.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 126 • Issue 7 • July 2000
Pages: 798 - 808
History
Received: Dec 23, 1998
Published online: Jul 1, 2000
Published in print: Jul 2000
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