Shell expand anchorage head and anchor bar

This invention discloses an expansion-shell anchoring, which comprises expansion-shell inner wedge and expansion-shell outer wedge, wherein the outer wedge covers the inner wedge; the inner wedge is a hollow round dome with a big bottom and a small top side, and the hollow cavity is connected with the top side and the bottom; the top of the inner wedge has longitudinal open slot, connecting with the hollow cavity and the top side; the lower external surface of the inner wedge has a beard which is connected with the bottom; the outer wedge is a cylinder with a hollow cavity, wherein the hollow cavity is connected with the bottom and the top side, the open slot of the outer wedge is mutually perpendicular in the outer wedge surface, separating several flaps in opposite direction. The invention also discloses an anchor bar with said expansion-shell anchoring, making the slip casting full and the anchor bar protecting layer evenly.