| 摘要 |
<p>A drain construction comprises a preformed assembly which is located in a trench which is then filled, around tne preformed assembly, with concrete or similar material. The preformed assembly comprises two angle-section wall members (10,11) which are held apart by spring spacers (21) to define a drainage slot, and a plastics pipe (12) which is slit along its length and the edges of the pipe along each side of the slit engaged in grooves (15) extending along the wall member (10, 11). The upper flanges of the wall members are flush with the ground surface so that water can drain from the surface by flowing down through the slot between the members and into the pipe (12). The spring spacers (21) separating the wall members permit the wall members to move relatively to one another as a result of thermal expansion or contraction, or other movement, of the surrounding material.</p> |
