GROUND ANCHORING METHOD

PURPOSE:To improve reliability on the bearing force of an anchor and working efficiency by a method wherein a process where an anchor tendon is manufactured in a preliminary hole formed in the vicinity of an anchor anchoring scheduled position is carried out simultaneously with a process where an anchor hole is bored. CONSTITUTION:A guide cylinder 2 is erected in a preliminary hole 1 formed in the vicinity of an anchor anchoring scheduled position and an anchor cable 3 is inserted in a guide cylinder 2. Through utilization of an injection hose in a sheath material 32, the sheath material 32 is filled with internal grout 4 to manufacture an anchor tendon A. An anchor hole 5 is then bored, the anchor tendon A is lifted from the preliminary hole 1 with the aid of a crane and the like and inserted in the anchor hole 5. A hose for injecting grout is inserted in the anchor hole 5 and a packer device 6 is set and external grout 7 is injected with a pressure. After the external grout 7 is cured, a PC steel material 31 is stretched by means of a jack for anchoring. This method manufactures quantities of the anchor tendons A simultaneously with a boring work.