Experimental and numerical studies on axially loaded reinforced square hollow section T-joints

Compressive strength of collar plate reinforced SHS T-joints: Effect of geometrical parameters and chord stress ratio

“…The difference of the enhancement ratio mainly comes from two aspects, namely the brace to chord width ratio (β) and the dimensions of the collar plate [16,18] . For example, the brace to chord width ratios of tests by Shao [18] are 0.25 to 0.69, comparing to 0.5 by Ozyurt et al [19] , and 0.53, 0.67 and 0.8 by Feng et al [20] . The thickness ratios of the collar plate to the chord (τ2) varied from 1.0 to 1.5 in the tests [12,19,20] .…”

“…For example, the brace to chord width ratios of tests by Shao [18] are 0.25 to 0.69, comparing to 0.5 by Ozyurt et al [19] , and 0.53, 0.67 and 0.8 by Feng et al [20] . The thickness ratios of the collar plate to the chord (τ2) varied from 1.0 to 1.5 in the tests [12,19,20] . Amongst the above tests, the yielding of chord flange or collar plate was found to be the control failure mode for most of the CPR SHS specimens.…”

“…Shao [18] investigated the structural performance of collar plate reinforced CHS T-joints under static load, and found the enhancement on compressive capacity is up to 22.6%. The enhancement of collar plate on strength for SHS joints is also apparent [12,19,20] , for example the tested enhancement ratios of compressive strength by Ozyurt et al [19] and Feng et al [20] are 83.6% and 123%, respectively. The difference of the enhancement ratio mainly comes from two aspects, namely the brace to chord width ratio (β) and the dimensions of the collar plate [16,18] .…”

“…Amongst the above tests, the yielding of chord flange or collar plate was found to be the control failure mode for most of the CPR SHS specimens. However, further parametric studies also observed the failure of chord web buckling, especially for CPR SHS joints with a high β and τ2 ratio [19,20] . This is mainly due to the "over-reinforcement" effect of the collar plate for the chord flange, which has also been observed for DPR SHS T-joints [21,22] .…”

“…by Ozyurt et al [19] , Feng et al [20] , Chang et al [21] and Lima et al [22] to reduce the thickness of the doubler plate. For the compressive strength design of CPR SHS joints, the equations for DPR joints by EC3 [23] and CIDECT [24] were found unconservative and unsafe in some cases [19] .…”