| 摘要 |
<p>PURPOSE:To prevent water from being accumulated in a conduit line, by making the cross section of the lower part of the inner surface of the conduit line whose sectional shape is a circle as a whole circular-arc-form, and by providing a catch-basin in the lowermost place of the inner surface of the conduit line. CONSTITUTION:The cross sectional shape of an underground common conduit line 1 is a circle as a whole, and the cross section of the inner surface of the conduit line 1 is circular-arc-form at least in the lower part of the inner surface, and in the lowermost place of the inner surface, a catch-basin 2 is provided. In this manner, since the section of the inner surface of the conduit line 1 is circular-arc-form, even if no inclination is provided on the floor surface of the conduit line 1, the whole water present in the conduit line 1 is made to flow in the lowermost place, and the catch-basin 2 is provided in the lowermost place. Thereby, water can be prevented from being accumulated in the conduit line 1.</p> |
