4. Decking

This part of the deck, which is primarily responsible for bearing operating overloads, has undergone structural and functional evolution over the past thirty years. Constructed from structures as diverse as concrete slabs, steel-concrete mixes and all-steel orthotropic slabs, each of which we will study in detail, deck decks must in all cases be designed to :

• withstand local forces generated by rolling overloads ;

• transmit these local forces to the main beams ;

• horizontal deck bracing;

• participate (except in special cases) in the overall bending of the main beams.