| 摘要 |
<p>The lower shaft section of the sewer consists of prefabricated concrete. It has a base with a drain, and a circular wall, with cylindrical apertures, aligned with the drain, for the mounting of sewer pipes. The wall (3) is formed as a hollow cylinder, and it is of esp. chosen thickness(s). The thickness allows all sizes of apertures for one shaft, to have an inserted section. The mounting section is of a sufficient length to allow the sealed mounting of connected sewer pipes.</p> |
