| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To carry out open-cut and back-filling in a short time, to abate traffic hindrance, to reduce the construction cost, and to lighten an environmental burden by reducing the amount of production of surplus soil. <P>SOLUTION: By using a cylindrical type cutter (6) provided with a cutting tooth (4) at its opening end, a semicircular cylinder-shaped earth-and-sand lump (16') is hollowed out of the earth and sand (16) and is separated from a road to form an excavated channel (22). A small channel is formed in the bottom of the excavated channel, where a pipe line or the like is laid. Then the earth-and-sand lump which is hollowed out is returned to its original position while its shape is maintained to restore the road. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
