Mondo Knows Facts
Heavy cast iron manhole covers stay grounded under fast traffic
Substantial metal mass keeps street covers from lifting under tyre suction
Street manhole covers are manufactured from heavy grey or ductile cast iron, often weighing over fifty kilograms each. Their substantial weight prevents high-speed traffic tyres from dislodging or vacuuming covers out of their frames, while resisting heavy lorry axle loads.
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Tags: engineering, roads, metals
Heavy cast iron manhole covers stay grounded under fast traffic: the short answers
- Where does this come from, and can I check it?
- Substantial metal mass keeps street covers from lifting under tyre suction. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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