Novel prestressed supporting device

The utility model relates to the supporting or reinforcing technology for rock engineering, in particularly to a novel prestressed supporting device, which mainly consists of a plurality of rods, an anchor head, an internal load-bearing plate, a protective cover, an expander, an exhaust pipe, an external load-bearing plate, a slurry plug, an upper cup support, a lower cup support, a nut and a corrugated pipe. At least one of the rods is a prestressed rod, two ends of the rod are provided with threads, and the inner end thereof is provided with the anchor head, the protective cover, the expander and the internal load-bearing plate. The anchor head consists of an expansion casing and a reverse wedge, the outer surface of the expansion casing is a cylindrical surface while the inner surface thereof is a conical surface, at least two full-length expansion joints are arranged on the expansion casing, at least one connecting point is arranged in the expansion joints, at least two annular projections are arranged on