Abstract: In a composite support structure such as a pallet wherein spaced apart opposed structural sheets are separated by a central core, the core including a plurality of spaced apart elongated channel-shaped members each presenting their longitudinally extending flange formations to the sheets and having longitudinally extending corrugated structural strips disposed between adjacent pairs of the channel-shaped members, each corrugated strip presenting alternate ridge segments thereof to each of adjacent pairs of the channel-shaped members and in abutment therewith with fasteners or the like securing each channel-shaped member to each corrugated strip formation in the regions of abutment.