Provided is a deck, configured for supporting a carriageable surface, including first structural girders defining a support surface for the carriageable surface; at least one second structural girder configured to position itself on the opposite side to said carriageable surface in relation to the first structural girders; diagonal girders integrally connecting the first and said second structural girders to each other, defining, for the deck, a truss; said first and said second structural girders include a core in concrete material: and an external reinforcement partially cladding the core and made of metallic material.