“ENHANCING PERFORMANCE OF STEEL TUBULAR JOINTS”

Abstract

Structures with tubular members are widely used in steel structures, due to their economical and functional advantages over other open sectional shapes. Applications of tubular joints in steel structures are found in steel bridges, space trusses, trussed Frames & steel latticed towers. In this research, performance enhancement of welded tubular joints composed of brace and chord members using steel plate stiffeners shall be studied through experimental tests and analytical methods. All T-tubular joints are investigated under brace member compression load. The experimental program includes compression tests on stiffened and un-stiffened T-joints with different geometrical parameters. The finite elements method is applied for stiffened and un-stiffened T-joints with different geometrical parameters and different cases of loading. The numerical study for each joint was carried out using the nonlinear finite element program ANSYS. Results from experimental tests are compared with the results which obtained from finite elements analysis for stiffened and un-stiffened tubular joints. Additionally, a comparison with strength equations for un-stiffened tubular joints which are available in major design code for steel structures, e.g. CIDECT is conducted. Existing design equations have been derived from isolated un-stiffened joint experiments or numerical analyses. However, there is relatively less research on stiffened tubular joints. The main objective of this study is to investigate the axial capacity of the circular un-stiffened and stiffened hollow section T-joint, by means of experiment and finite element analysis. Based on this experimental and analytical research, the applicability to current design equations is investigated. It will be possible to use equations for stiffened tubular joints design in design codes.