Double deck trains

[zn1]

there is somewhere a plan that would have used cartic trailers for a DD vehicle, it was purely an idea and quickly shelved.
as i have said before Bombardier have looked at the idea, even examined one of the surviving DD coaches and have said even using Bulleids idea, it couldnt be done today, as the way Bulleid built them wouldnt be acceptable today, even the underframe with its weight saving couldnt be used.....its a great dream, but the only place DD trains today could be used are on HS1 and hs2,

 

[Loki]

there is somewhere a plan that would have used cartic trailers for a DD vehicle, it was purely an idea and quickly shelved.
as i have said before Bombardier have looked at the idea, even examined one of the surviving DD coaches and have said even using Bulleids idea, it couldnt be done today, as the way Bulleid built them wouldnt be acceptable today, even the underframe with its weight saving couldnt be used.....its a great dream, but the only place DD trains today could be used are on HS1 and hs2,

I think most of us here would agree that the gauge is too restrictive. It seems even the smallest profile DD trains are too high. However whenever the capacity becomes a problem on a specific line, gauge clearance should be on the table in stead of automatically jumping to platform extensions.
Also all new infrastructure should be built to at least UIC GA gauge (platforms should be built so they can later be chopped easily to suit UIC gauge). More thinking for the future, less legacy systems. Good work on Crossrail tunnels and HS2 there.

 

[IKBrunel]

My impression is that most new or extended platforms are built with the last half metre cantilevered out from whatever supports are used. So they could be made narrower in future without complete rebuilds. This only accounts for a tiny % of platforms though. Lowering any UK platforms to European spec would be a different story.

 

[swt_passenger]

My impression is that most new or extended platforms are built with the last half metre cantilevered out from whatever supports are used. So they could be made narrower in future without complete rebuilds. This only accounts for a tiny % of platforms though. Lowering any UK platforms to European spec would be a different story.

Current design standards for new platforms do require a clear space under the platform edge, minimum 300mm deep and 480mm high, but it is there for safety purposes, mainly to allow someone falling from a platform to roll into the space if they are able to, and secondly to allow access by emergency services to someone trapped under a train.

I'd be surprised if having done that it could be removed for gauge clearance in future...

 

[Loki]

My impression is that most new or extended platforms are built with the last half metre cantilevered out from whatever supports are used. So they could be made narrower in future without complete rebuilds. This only accounts for a tiny % of platforms though. Lowering any UK platforms to European spec would be a different story.

For gauge clearance you don't have to actually lower the platform. In fact, here is a UK platform regauged to UIC in Nene valley:
http://www.flickr.com/photos/mickwhitelock/6627775813/sizes/l/
http://www.flickr.com/photos/badgergravling/9483630571/sizes/o/

The height has not been altered.

 

[jopsuk]

another east coast stock that wouldn't fit that diagram- due to the corners- are the Long Island Rail Road's double deckers (100mph big boxes!)

 

[DownSouth]

Which basically proves the point that its fine to produce rolling stock outside of standard national gauge if you clear the routes for it to operate.

Actually, I would say that double-stack containers, tri-level autoracks and bi-level coaches have been the de facto standard national gauge in the US for quite a while, with the various restricted areas being regarded as the anomalous cases.

It could be argued that it actually shows it's not always a good idea to have a nationally-regulated standard and that private enterprise is better at making improvements to the railways than a regulated railway.
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My impression is that most new or extended platforms are built with the last half metre cantilevered out from whatever supports are used. So they could be made narrower in future without complete rebuilds. This only accounts for a tiny % of platforms though. Lowering any UK platforms to European spec would be a different story.

Platform height is not a necessary feature of a loading gauge specification. You would find that most US and European passenger stock comes with fold-out steps because varying platform heights are quite normal.

There is no reason that high-level platforms wouldn't be allowed for continued use in the UK with a new loading gauge fit for double decker use (i.e. requiring straight sides, not a pinch point at floor height) with the stock having mid-level entry doors and the wheelchair/bike spaces between the doors and the ends.