The reams of buddleia growing out of the entire length of the Nine Elms viaduct (and indeed, many neglected buildings within about a half-mile distance of the viaduct) certainly didn't help the structural integrity.
Indeed it does not.
50mph bi Di, 5mph over viaduct.
What about the slots when Lumo isn't running, could a TPE or Northern run through then?
What does that mean?
You run them in one direction in quick succession.
Flighting means you run a bunch of services in one direction one after the other, then swap direction and run a bunch the other way rather than continually alternating direction.
It seems likely that the relaying work contributed to the collapse. Possibly a result of vibration from the plant operations, and/or increased lateral pressure from the fill or ballast during compaction. It would be quite a coincidence if the two were unconnected.
That's my hypothesis. It's not uncommon for structures to be very stable until disturbed.
Yes, though obviously with reduced power to weight ratio. It used to be booked traction on some of the Harrogate terminators.
It’s my opinion that third party structures surveys for years have been let’s say Tick Box!!!!!
Indeed I have been on 800-801 combos from Leeds to Hambleton before that did fine (not amazing) but fine.
In-house surveys have the same problem.
But ongoing engineering work on stations etc might. However, once the scale of the problem has been fully assessed and plans for remedial work are known longer term plans can be made for diversions.
What isn’t possible?I have been reliably informed it isn't possible
Unlikely the wall would fail under traffic like that as load is vertical down into the ballast. This failure mechanism looks like the parapet wall has been overloaded from sideways thrust and maybe like Nine Elms a safety handrail has then resulted in a cascade failure down the parapet wall length. ie the weight of the wall falling off then pulls the rest of wall down with it. When we did renewals across viaducts in London structures engineers were concerned about sideways thrust load onto the parapet walls so mandated small bucket excavators and narrow bladed dozers to prevent ballast being squeezed up against the parapet walls. They were constructed with standard london bricks and mortar condition was poor here the bridge looks like it used more substantial stones.
Seems to have made it: https://www.nationalrail.co.uk/service-disruptions/morpeth-20231008/
National Rail said:
Was thinking the same although, I wonder if the rails hit the retaining wall (either under a release of pressure otherwise a hit by the road rail vehicles), iirc wasn't there a similar wall collapse from a raised viaduct in South West London.
Yes, the Nine Elms one referred to in some of the posts above.
