| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure having the high slip prevention effect, and commonly usable for various uses, even in any case, in a slip prevention structure of an opening part cover of an underground catchment space.SOLUTION: A plurality of drain ports 2 are provided on an upper surface of an opening part cover 1 of an underground catchment space. A part between the mutual drain ports and a part between the drain port and the cover outer peripheral edge are formed of a rib 3, and a plurality of projection parts 4a and 4b are arranged on a rib upper surface. The drain port, the rib, and the projection part are uniformly arranged on the upper surface of the opening part cover. A sum total D of an area A of the rib exposure surface sum total except for a projection part place of the rib upper surface and a sum total C of the area occupied by the projection part on the rib upper surface in a sum total opening area B of the drain port, is respectively set by about 50%, and an engaging function part lower than the projection part is uniformly arranged on the rib exposure surface. |
