摘要 |
<p>A system for constructing narrow underground walls utilizing the slurry trench method is disclosed wherein a first apparatus (18, 60, 71) excavates from one end of a slurry filled trench and a second apparatus (21) is utilized for filling the trench with a wall forming material and at least a part of the excavating and/or filling apparatus is floated on the slurry in the trench. In one disclosed embodiment, narrow cut-off walls are formed by excavating from one end of a slurry filled trench and backfilling the trench at the opposite end by depositing therein a mixture of excavated soil and bentonite slurry from the trench, and includes a relatively large float (9) adapted to be immersed in the slurry to prevent loading on the trench walls and stabilizing the apparatus for excavating purposes. In a further embodiment, in combination with a float-fin (9), low pressure tires or crawler treads (11) bear a portion of the load and the distribution between the float and the ground engaging apparatus is accomplished by adjusting the buoyancy of the float, and the buoyancy of the float being adjusted by admitting or removing slumy or other liquid from the interior of the float. </p> |