Australia bridges steel components machining BBN Steel Structures was awarded by Australia to fabricate all steel components for bridges. BBN Steel Structures's scope of was to fabricate over 1,500 tons of steel bridge girders and other components such as elastomeric bearing sets, guard rails, scuppers, edge forms, bracing, splicing plates, channels, lifting lugs and more. The bridge designs consisted of four steel continuous girders with case insitu concrete decks.