Not sure what you classify it as, but how would you design such a weld? it seems difficult to determine how much capacity goes into the sandwich material and how much into the upper piece. The only way I'd do something like this is if the sandwich piece and top piece were fully joined somewhere else, say by puddle welds, or if this weld was really something superficial and non structural, used to only hold the pieces in place, or something of that sort.
M.S. Structural Engineering
Licensed Structural Engineer and Licensed Professional Engineer (Illinois)