Stress Concentration Factors in Tubular K-Joints under In-Plane Moment Loading
Publication: Journal of Structural Engineering
Volume 124, Issue 4
Abstract
An extensive parametric study is presented of the distributions of stress concentration factors in tubular K-joints commonly found in offshore platforms. The study covers a comprehensive range of geometric joint parameters for balanced in-plane moment loading. The results of the study were first used to assess two sets of widely used parametric equations, which predict the maximum stress concentration factors on the outer surfaces of the chord and the brace. The new database of finite-element results was then used to develop parametric equations for predicting stress concentration factors at key locations around the intersection on the outer as well as the inner surfaces of the chord. The reliability of the proposed and existing parametric equations was then assessed using an acrylic test joint database and some published test data measured from a steel model. Fracture mechanics fatigue calculations were also performed to demonstrate that the information provided from the proposed equations could be utilized to obtain accurate, and safe, fatigue life estimates.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 124 • Issue 4 • April 1998
Pages: 382 - 390
Copyright
Copyright © 1998 American Society of Civil Engineers.
History
Published online: Apr 1, 1998
Published in print: Apr 1998
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