| 摘要 |
<p>To counteract the erosion of the bottom of seas and lakes, and of banks and beaches as a result of wave motion and the effects of water currents, concrete is cast under water in a "stocking" (4) made of a thin plastics material, The "stocking" is first threaded over a hose (3a) cooperating with a concrete pump (5) and then progressively filled with concrete (6) while being laid on the bottom by means of a diver (8). The length of the "stocking" may be, for example, 25 metres. The surface or area to be protected is covered in this way with mutually parallel concrete stringers (6), one after the other, optionally in several layers. </p> |
