| 摘要 |
PROBLEM TO BE SOLVED: To provide a burying construction method for an underground buried object and a noncore boring device for shortening constructing time, capable of minimizing a cost and causing no construction trouble. SOLUTION: This noncore boring device 10 is provided with a tube 1, an annular outer bit 4 installed on the tip of the tube 1, an inner bit 5 for substantially blocking up an inner diameter part by being fitted to the inner diameter part of the outer bit 4 and a clamp mechanism 6 being fixed to the inner periphery of the tube 1 so as to be freely engageable and separable and connecting the inner bit 5 to the tip.
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