Confining T-joints by adding two outer hollow ring flanges welded to additional hollow circular pipe

摘要

Increasing the capacity of circular hollow section (CHS) T-joints is a challenge for the designers due to its closed nature that makes strengthening difficult as the traditional strengthening techniques focus on adding ring stiffeners inside the chord, these techniques require splitting the chord at each joint location into more than one part and this is not applicable for stiffening prefabricated and erected T-joints. This paper presents a proposed strengthening technique that is based on confining the T-joint by two outer hollow ring flanges welded to additional hollow circular pipe. A parametric study is carried out to investigate the effect of the hollow ring flanges diameter, the added elements thickness, and the spacing between the hollow outer ring flanges on increasing the capacity of T-joints for different values of beta (d(b)/d(0): brace diameter-to-chord diameter ratio) when the brace is either subjected to tension or compression force. Finally, it is observed that the compressive T-joints gain up to 267% of its original capacity and the tensile T-joints gain up to 65% of its original capacity.