| 摘要 |
A top piece (4) for a manhole structure (1) for, for example, a sewer system comprises an access part (6) and a cone (5) which connects to the access part (6) and can be placed on a manhole structure shaft (3) with a peripheral edge (17) on the side of the cone (5) situated opposite the access part (6). The cone (5) has a substantially outward curved basic shape. In the region of the transition (21) from the access part (6) to the cone (5) a reinforcement rib (22), which is substantially parallel to the plane in which the peripheral edge (17) is situated, is provided on the outer surface of the cone (5), extending over the entire periphery of the cone (5). This gives the cone (5) greater resistance to pressure forces in the region of the transistion (21) to the access part (6). |
