Modelling a "Skew" road bridge over a curved double track in 00

[Tallpaul69]

Can anyone suggest a source of any of the following alternatives to aid my making an 00 gauge model of a straight main (A) road bridge to cross a double track main line at an angle, but also the track is curved, with an inner radius 2ft. The tracks will dive under the road again when they have turned through approx 70 degrees from the first bridge position:-

1) A kit that could be adapted to this configuration

2) A drawing or set of drawings from which a bridge model could be produced.

3) A model maker they know for sure could undertake such a commission.

 

I should add that the bridge needs to be to GWR pattern. An alternative could be a BR pattern bridge erected in the period 1948-1968. Also the further road over track crossing is not scenic so will not need to be a proper bridge.

 

Many thanks 

Paul 

[Huw Griffiths]

Does this need to be 1 bridge - or could there be a road junction somewhere in the middle?

 

It just strikes me that one road - crossing the same stretch of line twice in this sort of distance - wouldn't be encountered very often - unless the road is actually 2 roads.

 

As for the "GWR pattern" or "BR pattern", I suspect that a lot of railway bridges crossing over railway lines would have been more likely to be built by (or for) local council highways departments - the exceptions often being for railway lines being rerouted, rebuilt or upgraded (eg for electrification).

 

Of course, I don't pretend to be an expert.

 

 

[rovex]

Think you need this

 

[Huw Griffiths]

5 hours ago, Huw Griffiths said:

Does this need to be 1 bridge - or could there be a road junction somewhere in the middle?

 

It just strikes me that one road - crossing the same stretch of line twice in this sort of distance - wouldn't be encountered very often - unless the road is actually 2 roads.

 

Thinking a bit more about this, if a situation like this looked like happening in real life, I suspect that the first thoughts would be to try and move the road, the railway line, or both - probably in that order - in an effort to avoid building any bridge at all.

 

If a bridge were unavoidable, they'd aim for 1 road to cross the railway line once, if possible - or separate bridges for separate roads / railway lines - something which might be needed at junctions.

 

Ultimately, bridges and other civil engineering structures are often likely to be expensive and disruptive to build (and maintain) - we might like them on layouts, as scenic breaks - in the real world, I suspect they'd be more likely to be avoided if possible.

 

Of course, it's your layout - so "Rule 1" applies ... .

 

 

By the way, that book is rather good - but it's possible to "go to town" with actually building model bridges.

 

[Michael Hodgson]

 

 

9 hours ago, Huw Griffiths said:

As for the "GWR pattern" or "BR pattern", I suspect that a lot of railway bridges crossing over railway lines would have been more likely to be built by (or for) local council highways departments - the exceptions often being for railway lines being rerouted, rebuilt or upgraded (eg for electrification).

 

I don't think so. 

 

The railway was the new boy on the scene when the Victorians built the railway whilst the highway was there all along - or you wouldn't need a bridge.    To get their enabling Act through Parliament, they'd have to specify how they intended to cross the highway, and in most cases a level crossing would have been the railways preferred option to keep down initial capital outlay, although they would need to employ a crossing keeper and provide a simple cottage.  Bridges would have been more appropriate where the terrain made it sensible.  The idea of closing level crossings and replacing with a bridge for better safety/less disruption to traffic is much more recent and due to 20th Century increase in car ownership.

 

Two bridges in quick succession carrying the same road over the same line with no intervening junctions seems improbable, though it might have happened if there was some problem to prevent you diverting either the road or the railway.

[Tallpaul69]

22 hours ago, Huw Griffiths said:

Does this need to be 1 bridge - or could there be a road junction somewhere in the middle?

 

It just strikes me that one road - crossing the same stretch of line twice in this sort of distance - wouldn't be encountered very often - unless the road is actually 2 roads.

 

Huw,

the exact  layout of the roads has yet to be finalised. Yes, the road over the bridge I need to build could join another road which which would run along the centre of the layout throwing off a station approach road before the junction and disappearing over the second (non scenic) bridge.

Cheers

Paul

[Tallpaul69]

22 hours ago, rovex said:

Think you need this

 

Good thinking Rovex!

I have found and ordered a copy of this book.

Cheers

Paul

[Huw Griffiths]

From some of my posts, it probably shows that I live in a "new town".

 

Cwmbran was designated as a "new town" after the war - prior to that, it was just a number of villages.

 

Most of the roads in Cwmbran didn't exist when the railways were built - so, where they needed to cross railway lines, they needed to be threaded over and under the lines - generally using Cwmbran Develeopment Corporation standard concrete designs.

 

In fact, some main roads in Cwmbran actually used old railway alignments.

 

Ultimately though, Cwmbran is one of those places where the railways often came first (or just disappeared). I'm sure I would have seen a very different picture if I'd looked somewhere like Cardiff.

 

Sorry about the confusion.