Analytical study of ultimate strength of tubular X and Y joints
General Material Designation
[Thesis]
First Statement of Responsibility
J. S. Jubran
Subsequent Statement of Responsibility
W. F. Cofer
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
Washington State University
Date of Publication, Distribution, etc.
1992
PHYSICAL DESCRIPTION
Specific Material Designation and Extent of Item
471
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
Ph.D.
Body granting the degree
Washington State University
Text preceding or following the note
1992
SUMMARY OR ABSTRACT
Text of Note
In this study, four basic tubular connections were analyzed to determine the effects of different design parameters on their ultimate behavior. Twelve different models were analyzed for axial tension, axial compression, and in-plane moment. The analyses were performed using the Finite Element program, TUBJNT, which takes into account large deformation, elastic-plastic behavior, and cracking in the form of Continuum Damage Mechanics. In addition, the effects of load interaction and hydrostatic pressure were also considered. The effect of the branch to chord diameter ratio, usd\beta,usd on the interaction equations was investigated for joints under axial tension and axial compression with in-plane moment. It was found that the interaction between compression and bending is greatly dependent on usd\beta,usd while that for tension and bending is much less dependent. New interaction equations are derived for compression and bending which include the effect of usd\beta.usd The interaction equations for tension and bending were taken to be independent of usd\beta.usd The results of the numerical study were compared to those obtained experimentally. New formats for design equations are derived using a simplified analytical model which is based on the ring model. The new design equations were calibrated against the numerical results. The hydrostatic pressure was found to have a great influence on the capacity of joints under tension. A pressure value of approximately two thirds of the collapse pressure for the chord was found to reduce the capacity of a T joint with a usd\betausd value of 1.0 by about 29 percent. The results for joints under axial compression and pressure have shown that the same value of pressure increases the strength by about 11 percent for a DT joint with usd\betausd value of 1.0. The effect of pressure on the in-plane bending capacity was very small, especially for joints with small usd\betausd ratios.