Time I was back, and here are some pictures I thought I had lost. They will be the start of a public collection of notes on arch bridge damage.
Let's begin with North Bridge, Doncaster. These photos could not be repeated because the bridge has been reclad since they were taken.
The drop shown here is of long standing and is typical of what happens to bridges on flood plains. the fence posts bolted to the brickwork emphasise the drop in the middle of the first span. Obviously the posts were set out off the brickwork, because the fence has been smoothed through.
The same bridge exhibited this strange condition. It is quite unusual for Staffordshire Blues to deteriorate in this way. the fact that it is very local gives a clue to the fact that a tanker of very nasty chemicals had a crash on the bridge. Note hw the damage is localised. theere is a clear line at the bottom, where the chemical settled on to the backing and came out through the side.
The twisted arch at Randalholme is really very unusual. When it was first described to me I thought it must be a square bridge with walls introduced on the skew later but that doesn't seem tobe the case. can anyone offer a clue as to why it should be built like this?