| 摘要 |
<p>The construction of a filter matting for lining the bottoms of canals, and other waterways, has one roughened surface with open hollow zones towards the bottom. The design gives the matting a longer life as it withstands the counter movements experienced between the roughened surface of the filter matting and the bottom of the canal. The roughened layer of the matting has a sufficiently dense structure to prevent base shifts from hollow zone to hollow zone. the hollow zones are constructed so that they are in the form of open recesses in the under surface of the matting, or by strips running across the fall of the slope. The end surface of the strips in the direction of the fall of the slope are the same size or larger than the open ends of the hollow zones ranging in the same direction of neighbouring filter matting sections, so that they can be covered. When the dimensions of the strips match the hollow zones, projecting strips can be used to engage into the zones to lock filter matting sections together.</p> |
