Prefabricated steel rib bottom plate-concrete overlapped hollow floor system

The invention discloses a prefabricated steel rib bottom plate-concrete overlapped hollow floor system, which comprises a prefabricated concrete bottom plate 1, steel ribs 2, prefabricated baseboard constructional steel bars 3, reserved holes 4 on the steel ribs, cross perforating prestressing or non-prestressing steel bars, steel wires or steel strands 5, a hollow formwork supporting frame 6, a hollow formwork top plate 7 and cast-in-situ overlapping layer concrete 8. The invention has the characteristics that the fabricated concrete overlapped hollow floor system comprises the prefabricated concrete bottom plate 1 with the steel ribs 2. A construction method comprises the following steps of: arranging a plate bottom supporting system; installing the prefabricated concrete bottom plate 1 with the steel ribs, placing both ends of the the prefabricated concrete bottom plate on load bearing walls (beams), and stretching the prefabricated baseboard constructional steel bars 3 into a wall (beam) steel bar cage; arranging the cross perforating prestressing or non-prestressing steel bars, steel wires or steel strands 5; installing the hollow formwork supporting frame 6 and the top plate 7, and pouring overlapping layer concrete 8; and curing and removing the supporting system under the plate. The invention has the advantages of large bearing force, good shock resistance, easy factory production, convenient construction, concrete saving, template saving, a few supports, good fireproof performance, large floor clearance and the like. The invention is especially suitable for high-rise buildings and floor systems with large-span structures.