The high strengths of steel allow small cross-sections of beams or girders and therefore a low dead load of the structure. It was thus possible to develop the light-weight "orthotropic plate" steel decks for roadways, which have now become common with an asphalt wearing course, 60 to 80 mm thick.
The pioneers of this orthotropic plate construction called it by the less mysterious and less scientific name "stiffened steel slabs". Plain steel plate, stiffened by cells or ribs, forms the chord of both the transverse cross girders and the longitudinal main-girders. Simultaneously it acts as a wind girder. This bridge deck owes its successful application mainly to mechanized welding, which is now in general use and which has greatly influenced the design of steel bridges.