| 摘要 |
PURPOSE: An anti-slip manhole cover is provided to improve an anti-slip function by installing high protrusions and low protrusions on the top end of the manhole cover in a zigzag shape. CONSTITUTION: An anti-slip manhole cover(10) is comprised as follows. High protrusions(16) and low protrusions(15) are continuously formed in a zigzag shape at uniform intervals on the top portion(11) of the manhole cover except mark attachment surfaces(18) and multiple drain holes(14). The protrusions are formed in a conical shape. The high protrusions have a height of 4-6 mm, and the low protrusions have a height of 7-10 mm. |
