Beam-Shell contact in Abaqus

Hello everybody.

I am doing my diploma project and I have to model an off-shore oil-rig in Abaqus. It's a metallic truss-type system. I've defined all of the elements composing the structure as wire elements and the decks as solids. Does anybody know how to define the contact between the decks and the supporting beams? The decks are supposed to be bolted to the beams.