Autoroatation self-expansion type anchor rod

The utility model relates to an autoroatation self-expansion type anchor rod used for tunnel engineering construction. The autoroatation self-expansion type anchor rod is provided with a long-rod-shaped anchoring head internally provided with a grouting hole, the top of the anchoring head is provided with an alloy drill bit in a connected mode. A strip-shaped square hole internally provided with an elastic self-expansion wedge block is formed in an anchoring head rod body. The elastic self-expansion wedge block comprises an inverted-V-shaped spring fixed to the anchoring head rod body and two wedge-shaped blocks symmetrically attached to the outer edge of the inverted-V-shaped spring. At ordinary times, after the inverted-V-shaped spring is compressed and folded, a segment of connection steel wire is welded between the tails of the two wedge-shaped blocks, so that the two wedge-shaped blocks can be folded and stored in the strip-shaped square hole in the anchoring head rod body; when the connection steel wire is broken, the two ends of the tails of the inverted-V-shaped spring are opened automatically to make the tails of the two wedge-shaped blocks extend out of the anchoring head rod body, and the tail of the anchoring head is provided with internal threads connected with an anchor rod body in a matched mode. The autoroatation self-expansion type anchor rod is reasonable in structure, convenient and fast to construct, good in anchoring strength and supporting effect and capable of keeping the completeness and stability of surrounding rock to the maximum degree.