NUMERICAL STUDY ON THE ULTIMATE CAPACITY OF UNSTIFFENEDTUBULAR T-JOINT WITH LARGE DIAMETER CHORD

摘要

Unstiffened tubular joints are widely used in spatial structures with circular hollow section (CHS) members. Thisrnkind of joints is often assumed to be hinge joints in regular structural design. However, for unstiffened tubularrnjoints with big diameter members, the joint stiffness is too big and the bending moments can not be ignored anyrnmore in the joint design. In this paper, the ultimate capacity of CHS T-joints with large diameter chord underrnbrace axial compression was analyzed numerically with finite element method. The bending moment in thernchord was controlled by applying compensation moment at the chord ends and the effect of the bending momentrnon the joint ultimate capacity was studied. By comparison, it was proved that chord bending moment had similarrneffect on the joint capacity as the axial force in the chord. Suggestion was then made on how to consider thernchord bending moment in the joint design.