Installing bridges

[MasonJar]

This may be a silly question, but does anyone have any advice / guidance / photos (!) of how bridges and abutments connect - including the plywood or whatever you are using for subroadbed?

I am having trouble imagining how all this comes together. If anyone has a picture... well, you know how much that would be worth!

Thanks!

Andrew

 

[shamus]

Hi Andrew,
I don't know if this is what you are looking for, but I always use a sort of subroadbed under my bridges wich goes direct into the plaster area.
Shamus

 

[MasonJar]

Thanks for the picture Shamus!

I am looking for more of a "plan" about how the stuff fits together, so I can answer questions like:

- If I have a 30' bridge, should the gap be 30' (or more, or less???)

- Does the bridge rest on the abutment (I know they do in real life, but what about modelling) or on the subroadbed?

- How to you tie all these pieces (bridge, subroad, roadbed, track, abutment) together so the thing is structurally sound?

- How does the cork roadbed factor into this?

Andrew

 

[shamus]

Originally posted by MasonJar
Thanks for the picture Shamus!

I am looking for more of a "plan" about how the stuff fits together, so I can answer questions like:

- If I have a 30' bridge, should the gap be 30' (or more, or less???)

- Does the bridge rest on the abutment (I know they do in real life, but what about modelling) or on the subroadbed?

- How to you tie all these pieces (bridge, subroad, roadbed, track, abutment) together so the thing is structurally sound?

- How does the cork roadbed factor into this?

Andrew

Okay, if your bridge is 30" then the subroadbed (Which forms the bridge) would have to be at least 33" giving you 1 and 1/2" eitherside to rest on the main frame.
Don't use cork on a bridge, just marry up the bridge height either side.
The bridge will rest on the abutments, which should have some sort of support underneath.

Shamus

 

[Ray Marinaccio]

Masonjar
I saw a series of articles in MR called ABC's of bridges back in 1988. I only have Aug. and Oct not sure how many others there were. They may help.

 

[jim currie]

andrew

what kind of track are you using on first layout i hand laid track and all bridges were built on bench supports and all except track, then placed on layout then of track laid right over bridge .worked well for me dont know if anyone else has tried this.

 

[Drew1125]

Hi Andrew!
I don't know if this will help, but here's how I built a couple of bridges on my latest layout project...

This one is called the Catt's Creek bridge.
I built it at the workbench, using a piece of flex-track, some styrene, a couple of Atlas girders, & some H&R stone sheet...

 

[Drew1125]

After everything was painted, I installed it onto the foam scenic base, cutting places in the foam to accomodate the piers, & shimming the bottom of the piers with cardboard to connect them with the scenery...

 

[Drew1125]

Then using sculptamold, plaster, & various ground cover, I built the scenery up around the bridge...

 

[MasonJar]

Thanks for suggestions everyone, and thanks Charlie for the pictures...

Andrew