| 摘要 |
The invention relates to a subterranean drainage structure 50 with a plurality of similarly dimensioned drainage cells 30, 40 formed into a regular grid comprising at least one horizontal layer that has a vertical access chamber formed by omission of at least one cell 30, 40 from the or each layer. A base 20 is positioned at the lower end of the chamber, and fixing means 3, 4, (9 figure 3) are provided for fixing the base 20 to at least one of the cells 30, 40 adjacent the chamber. A later embodiment relates to a subterranean drainage structure inspection chamber base 20 comprising a platform (11 figure 2) extending across the base 20 in a first direction. A substantially flat surface opposes the platform (11 figure 2) to support a geotextile membrane placed against it. The base 20 includes fixing means 3, 4, (9 figure 3) for fixing the base 20 to an adjacent element 30, 40. |
