Abstract: A work platform (10) supported by transverse beams (20) and a pair of elongated side frame assemblies spaced apart by the transverse beams (20) is disclosed. The side frame assemblies (18) include longitudinal beams (28) that support a plurality of axles (32) that support a plurality of rollers (30) with the ends of the axles (32) being supported by the longitudinal beams (28). The rollers (30) provide support for the work platform (10) and allow the work platform (10) to travel along the upper surfaces (34) of lower confronting flanges (16) of work site beams (14), such as are commonly used in bridge construction. The work platform (10) includes lifting arms (66) that serve to raise the rollers (30) up off from the flanges (16) such that the work platform (10) is prevented from travel along the work site beams (14). The transverse frame member (20) includes a member into which a nail can be driven to in that manner allow a deck (22) of wood to be nailed directly to the cross frame members (20).