| 摘要 |
<p>PURPOSE:To reduce the number of nozzles used in the excavation of a trench by high-pressure water jet by a method in which plural high-pressure water nozzles are arranged in one row and wedging plates to disintegrate an excavated trench are arranged in the rear side of the nozzle row. CONSTITUTION:In a seabed excavator, high-pressure water nozzles 1 are provided in a multistaged manner in several groups, where the nozzles 1 of each group are aligned sideways at given intervals. In this case, the intervals between the nozzles are determined so that the intervals at which unexcavated portion (b) remains between the excavated portion (a) by each nozzle 1 becomes ones at which the width of the unexacated portion (b) is almost equal to that of the excavated portion (a). On the rear side of the nozzle group 1 thus arranged, wedging plates 2 whose width is greater than that of the excavated portion (a) are provided one nozzle apart. These nozzles 1 and wedging plates 2 are attached to the plow 3 of the excavator and when the excavator is advanced, the unexcavated portion (b) is crushed and disintegrated by the wedging plates 2.</p> |
