| 摘要 |
<p>Prodn. of a water-tight pit in water-logged strata comprises using a piling wall with at least one water-tight "window" which is filled by allowing ground water to flow through a permeable layer. An entropy-elastic body is inserted into the "window", inflated by pressure brought in from the ground surface, and so pressed tightly against the "window"; the "window" space filled by this body is connected to the surface by a pipe plus valve through which the remaining space in the "window" is filled during or after releasing the pressure again. This body is a balloon. Simple inexpensive system with rapidly filled "window", enables pit to be rapidly flooded again when working is completed.</p> |
