Prefabricated reinforced concrete stair

The utility model is an improvement of the existing prefabricated reinforcement and is characterized in that the two axial sides of the prefabricated stair are of beam structures; stair plates, treads and the two side beams form a whole U-shaped structure; the two ends of the two side beam structures are embedded with a steel-structure connecting and installing connector, which leads force on the treads of the stair and rest platforms to be born by the two side beams. Therefore, the utility model can greatly reduce the thickness of the stair plates and consumption of the reinforcement, not only can greatly reduce the weight of the prefabricated reinforced concrete stair, has high structural strength, can adopt a hollow structure, can reduce the weight of the reinforced concrete stair by about 50% compared with the plate structure by theoretically calculating the weight of the beam structure stair, but also provides structural guarantee for manufacturing large-span stairs. The steel-structure connecting and installing connector is directly connected with a building structure, has simple installation, has structural strength after the installation is finished, and can be used immediately after the installation is finished; the structural strength of the installing connector is high, the installing connector forms a strong node; and the prefabricated reinforced concrete stair has good shearing resistance, torsion resistance and shock resistance, has complete dismountability, and greens buildings.