To miniaturize an anchor pedestal and to reduce its weight by driving lock bolts into the ground around an anchor body, and covering the head ends of the lock bolts with the anchor pedestal.

Tension members 16 of an anchor body 14 driven into the ground 12 are tensed and anchored at the head part, and the tension is led into the ground 12 through an anchor pedestal 18. Lock bolts 20 are driven and anchored into the ground 12 around the anchor body 14, and compressive force generated by driving the bolts 20 is added to the tension of the tension members 16 and imparted to the ground 12. In this case, the bolts 20 are driven and anchored into the ground 12 in a plurality of places isometrically separated around the anchor body 14 within a range of the head ends 20a being covered with the pedestal 18. In addition, the bolts 20 are driven in a non-parallel state to the anchor body 14 such as in open angle shape in the facing positions through the anchor body 14. The lead-in force is therefore allotted to the anchor body 14 and the lock bolts 20, so that the anchor pedestal 18 can be miniaturized and reduced in weight.