Abstract: In a fabricated rigid floor deck structure assembled from a plurality of similar floor sections, a floor section is formed for engagement with an adjacent similar section to form an interlocked floor structure. Each floor section is constructed from an elongate plate having a male and a female flange each having a U-shaped cross section. The female flange has one leg depending from one edge of the plate with its other leg positioned outwardly of the one edge to define an upwardly opening channel laterally outward from the plate. The male flange has one leg depending from the opposite edge of the plate with its other leg positioned inwardly of the other edge adjacent the bottom surface of the plate. The flanges are dimensioned so that adjacent floor sections are locked together in suitable alignment by placing the male flange into the channel defined by the female flange of an adjacent aligned floor section.