| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an improvement method of non-excavating soil directly below an existing structure which can realize favorable space efficiency of a working space and which can infuse a soil-improvement material with precision. <P>SOLUTION: In the position measurement of a drill head member 50 using a three-dimensional measuring instrument 70, the three-dimensional measuring instrument 70 is inserted to an inside hollow part from the rear end 17a side of a casing rod member 17, and is made to reach the interior of a hollow part which is inside the drill head member 50 before performing a drawing process of connecting the tip 17c of another following casing rod member 17 to the rear end 17a of the casing rod member 17 in a drilling ending position where a rod propulsive device 20 is positioned. By the measurement, when the drill head member 50 has reached the requested position, the tip 80a of an inserted medical fluid injecting pipe member 80 is struck against the rear end surface 61a of a cylindrical plug 61 of an excavation plate member 60, thus the excavation plate member 60 is separated from the drill head member 50. <P>COPYRIGHT: (C)2008,JPO&INPIT |
