Trying to check the strength adequacy of a RHS-hollow-section beam sitting on top of several parallel PFC-section beams with respect to web crushing (WC)and web buckling (WB) of the hollow section. The hollow section is welded to the each PFC with two lines of 6mm fillet weld. RHS member is aligned perpendicular to PFCs.
Two possible assumptions and one is probably not correct:
(1) The force from the RHS sitting on the PFC is transferred through the welds to the PFC, and the length of the welds is taken as the bearing length for checking WC and WB of the PFC.
(2) Even though one is welded to the other, the bearing is determined as if the welds are not there by considering a stiff bearing length determined using spread through flange of PFC and add that to the web thickness of the PFC. Using this assumption gives me much smaller bearing and web buckling capacities in comparison with those obtained using assumption (1).
Which of these two assumptions is correct ?
Two possible assumptions and one is probably not correct:
(1) The force from the RHS sitting on the PFC is transferred through the welds to the PFC, and the length of the welds is taken as the bearing length for checking WC and WB of the PFC.
(2) Even though one is welded to the other, the bearing is determined as if the welds are not there by considering a stiff bearing length determined using spread through flange of PFC and add that to the web thickness of the PFC. Using this assumption gives me much smaller bearing and web buckling capacities in comparison with those obtained using assumption (1).
Which of these two assumptions is correct ?