On 26/03/2021 12:23, Mathew Newton wrote:
On Friday, 26 March 2021 at 07:20:51 UTC, Mike Halmarack wrote:

Rush hour's a torment when you've got one of these seveal feet away.
I tried several things: pouring sand between the frame and the lid,
which worked for a while, expanding foam with similar effect.
In the end it had to be a replacement.

I've noticed that all the manhole covers on our 'new' (2007) estate are made up of two triangles, presumably as each piece is unable to rock regardless how ill fitting they might be/become. That or some health and safety requirement to minimise weight for lifting them out.

It is to make them non-rocking. If it is like the one in my driveway (I
don't know why United Utilities fitted one suitable for HGVs to drive
over), it actually makes them heavier, because each half has its own
stiffening rib on the hypotenuse, but the two halves are (loosely)
linked together, so have to be lifted as one.

There used to be a simple rectangular, cast iron one, but only suitable
for a driveway. While investigating a collapsed sewer, they noticed that
the lid was cracked in one corner, but also that it stood 1/2" higher
than the drive and decided to replace it. They had to rebuild the top of
the chamber to adjust for the new, deeper frame and to get the height
right. I'd have been happy with just replacing the lid!

And thank God (under the old rules), next-door's kitchen drained into
that chamber (although the rest of their house doesn't), as it made it a
pre-1937, shared sewer pipe, which, if it were not shared would have
been my responsibility and horrendously expensive to fix, as it had
collapsed just under my drive and again in the middle of the road.