| 摘要 |
An apparatus for flood protection of a manhole (10) comprises a vertical pipe slidably mounted for vertical movement within the casing of a manhole (20), and a seal (52) adapted to seal between the pipe and the casing. The pipe has at least one buoyant portion (40, 42) such that the pipe (30) rises vertically as the buoyant portion (40, 42) rises. |
