PURPOSE: To obtain strong holding force by applying striking force directly to an anchor body and to ensure effective holding force against cracks occurring to places around a foot hole after execution of work.

CONSTITUTION: An anchor body 21 has an external thread 23 and a head 24 for being struck on one end thereof while being as a threaded shaft 22 having a bottomed cylindrical part 25 on the other end thereof. A plurality of open leg pieces 27 are formed with a plurality of split grooves 26 provided, extending in the axial direction from the opening end of the cylindrical part 25, and sawtooth crushing edges 28 are provided to the front end of the open leg pieces 27. A crushed pieces-housing part 34 and an extraction-preventing shoulder 36 are formed between a bottom part 35 and a large-diameter side of a tapered part 33 on a taper plug 31 inserted into the cylindrical part 25.