ULTIMATE STRENGTH FORMULAE FOR RHS-CHS T-JOINTS UNDER AXIAL COMPRESSION

RHS-CHS T-joints and H-CHS T-joints are different in load-transferring mechanism and ultimate load capacity, although they are similar in configurations. To perform a precise FE analysis, analytic models using the "Chord Constraint Method" were utilized, which could exclude the bending effect of the chord, to obtain the "true" strength of joints. The "true" strength reflected the mechanical property of bare joints in which the influences of chord length and boundary conditions were eliminated. Totally 192 RHS-CHS T-joints and 192 H-CHS T-joints were analyzed. It indicated that RHS-CHS T-joints were more susceptible to the longitudinal plates of the brace compared with H-CHS T-joints. The results showed that the design formulae of CIDECT Design Guide made a conservative estimation for the strength of RHS-CHS T-joints. Revisions were made in this paper based on the design formulae in CIDECT Design Guide, and it provided good accuracy.