| 摘要 |
<p>Drainage element (1) comprises column elements spaced and arranged in rows. A tunnel opening (10) for an inspection channel (11) is formed on each side wall of the drainage element. The inspection channel joined the tunnel openings. Preferred Features: The drainage element has a rectangular cross-section so that two longer longitudinal walls (7) and two shorter transverse walls (8) are formed by the side walls which delimit the hollow chamber of the drainage element.</p> |
