I am attempting to analyze a frame structure that is comprised of C-channel beams that are bolted together along each side using solid blocks while corners are welded together with gusseting. To run the simulation, I excluded the fillet welds attaching the gussets to beams and manually created bonded contact sets between them.

My understanding is that when you apply a bonded contact between two surfaces, the surfaces should not shear w.r.t. one another. However, when I run the simulation and create an exaggerated displacement plot, the gussets are shown completely shearing off of one of the beams that they are bonded to. All of the contact sets between gusset and beam surfaces have been created manually. I attempted to add edge weld contact sets but since these aren't sheet metal parts, I get an error. I also tried defining the bond contact between gusset and the two beam surfaces as one contact (gusset-beam and gusset-other beam) set as well as two separate contact sets (beam-gusset-beam). Both gave the same result.

This simulation was run with only a 1 lb load just to test the setup, so displacements are very small.

Any insights are appreciated. Thanks