This might belong in layout design but it is a prototype question at the root so I placed it here.
I have found clearance heights for railroad bridges over highways , 16’-18’ or a bridge height of 2.5" in HO.
But , I cannot find clearance heights for highways (or any other type bridge) over a railroad track.
I am modeling 1920’s-1960’s steam and diesel, freight and passenger trains.
Are there any resources with clear cut #'S on clearance heights?
look up the plate clearance for your era.
Association of American Railroads Clearance Diagrams for Interchange Service
http://www.icrr.net/plates.htm
22’-3’ from the top of rail for autoracks or double stacks. But usually a little more as a factor of safety. Canada’s current minimum appears to be 23’-5".
For model railroads best use NMRA standard as absolute minimum (22’ for the “Classic” period about 22’-9" for “Modern”) http://www.nmra.org/sites/default/files/standards/sandrp/pdf/s-7_2012.02.pdf
but there may be some models that require more clearence.
Modern standards for UP, 23ft4in, BNSF, 23’6", top of rail to bottom of bridge. I suspect other railroads and state DOT’s are similar.
Google is your friend.
https://www.up.com/cs/groups/public/documents/document/pdf_rr_grade_sep_projects.pdf
Uhhhhhh…I could be wrong but I don’t think you guys are answering the OPs question? He’s looking for the height of a bridge over a highway; NOT the height of the bridge over a railroad track.
Tom
I dunno Tom, I read it as “he knows the height of a bridge over a highway, 16’ or more” (most bridges over a freeway are marked if they are 14’ or less) and wants to know the height of a bridge over a railroad, which I think has been answered pretty well. [:)]
Mike.
The NMRA states minimum bridge clearence over the the top rail in the era of 1920-1969 is 22 feet and comes out to 4 1/8 inches in S scale.
[D)] Doh! - You’re absolutely right, Mike. I was the one reading it incorrectly. That’s what I get for looking at a thread before I’ve completely woken up. [%-)]
Tom
I know what you mean! [(-D]
Mike.
I was aware DSchmidt won the cookie on this one when I posted. I gotta tell you some of the posts on my computer run right off the screen and I can only see half the post I wonder if other people have that problem or it’s just my computer. At any rate I was just curious what 22 feet scaled to in S scale. I’m just glad I don’t have to find the 17 feet plus more for easements to get up to that 4 1/8 inches. I would be through the wall and 10 feet into the backyard.
Does anyone know how to correct the problem of posts that run off the screen any help would be appreciated
Customer Service might be able to help you with your computer’s interpretation of the software Kalmbach is using here.
As for S Scale and 22’, it works out to just over 4.1". Make it 4 1/8" and you’ll be close enough for government work.