| 摘要 |
PROBLEM TO BE SOLVED: To provide an underdrain-forming apparatus by which a vertical port passage is kept even if both opposite surfaces of bored groove trace is made closely narrow and blocked by passage of time, and capable of favorably keeping draining property and air ventilation of an underdrain by presence of the vertical port passage. SOLUTION: This underdrain-forming apparatus is obtained by connecting a machine frame 3 to a traveling machine body 1 by a connecting mechanism 2, swingably vertically installing a boring bema 4 in advancing direction by a swinging mechanism 5 in the machine frame, installing a bullet body 14 capable of forming the underdrain in the soil in the lower part of the boring beam, installing an enlarging member 15 capable of forming a vertical port passage T opening on the ground surface by enlarging one surface of a boring trace groove S extended and formed in the vertical direction in the soil by the boring beam at the backward position in the advancing direction of the boring beam, and installing an enlarging mechanism 16 for carrying out the enlarging action of the enlarging member. COPYRIGHT: (C)2007,JPO&INPIT
|
