Why is the cover of manhole circle in shape?

Answer 1

A circular manhole has the following advantages over all other shapes:
1. Constant diameter prevents the possibility of the cover falling into the "personhole".
2. There cover fits regardless of its "clock" position.
3. The heavy cover can be rolled on its edge to promote removal and replacement.
4. The absence of corners makes the circular shape more "foot friendly"

Answer 2

Because no matter how u rotate a circle manhole cover , your manhole will always covered , but if you try to rotate a square cover , parts of the manhole may become open

Answer 3

You see a manhole's cover is too heavy, and transferering it from one place to the another is more easier if it is circular in shape(by rolling), unlike a rectangular cover which you have to drag or lift.

Answer 4

Those covers can weigh around 300 pounds. It is no easy task to lift out a cover should it fall into the hole. A round cover will not accidentally fall into the hole during removal or replacement.

Answer 5

For easy differentiate identification between a manhole and other utilities services such as IC Inspection chamber which has a rectangular shape.

Answer 6

so that they do not fall inside the manhole. square or rectangular covers can fall inside the manhole (diagonally) during removal whereas circular cannot.

Answer 7

Because it is the strongest geometric shape for the job and is less likely to buckle than a shapes who's sides are NOT equidistant from the centre eg a triangle, rectangle or square

Answer 8

A circle can't fall in a square can (on the diag)

Answer 9

Its better to cover a round hole with a round cover.

Answer 10

People are more of a circle than square...