# Has Anyone Attempted a Concrete Viaduct? Do Tell.



## CapeCodSteam (Jan 2, 2008)

Doug and I are half way through the wood trestle and now looking at what to do for the 2nd span. It needs to be about 2' high, 12' long and will support two lines.

Any experiences you guys have had playing with concrete would be most appreciated.

Thanks in advance.


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## Dave F (Jan 2, 2008)

I started this thread a while back... 

http://www.mylargescale.com/Community/Forums/tabid/56/aff/9/aft/113591/afv/topic/Default.aspx 

It may shed some light for you. I haven't built my bridge...yet. I'll post up when I do..


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## John J (Dec 29, 2007)

Take a look at this. http://www.mylargescale.com/Communi...fault.aspx

I just posted it.

One could pour the two arches and verticals laying on thier side. Each one independant of the other. Then Pour the Road Bed ( top sections) The use some kind of epoxy to join the whole thing together 


JJ


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## Mike Reilley (Jan 2, 2008)

You might consider using foam. I've seen a lot of viaducts made from foam on GRR visits. Some folks carve the blocks in the foam to look like rocks. Some cut in square patterns to represent cut stone. The latest rage here in San Diego is using Precision Board which is a very dense foam. See examples at http://www.rainbowridgekits.com/triplearch24bridge.htm ... just page down to the bottom. One advantage of PB is that you can buy the PB already engraved for brick if that is what you desire.


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## Jerry Barnes (Jan 2, 2008)

Mine is made with the blue construction foam. Scribed in some block patterns and painted it with artist acrylics. SOme guys put a concrete skim coat over theirs. Basic support is treated lumber underneath. Pix on my web site, don't seem to have any on my storage here.


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## SE18 (Feb 21, 2008)

yours truly 










Dave V


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## Daniel Peck (Mar 31, 2009)

I can build one out of metal and then have a textur paint put on it....


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## SE18 (Feb 21, 2008)

.


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## SE18 (Feb 21, 2008)

day 4 stress test


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## SE18 (Feb 21, 2008)

any questions? 

.


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## Cougar Rock Rail (Jan 2, 2008)

Here are a few pictures of my cast-in-place concrete viaduct. I used wood forms, aluminum for the underside curves braced with wood, some rebar in the piers and across the top. The center is approximately 10' diameter, and the whole thing has a 2% slope built into it.


































The above pictures were with the forms just stripped--it lightened up quite a bit. I drilled in some brass railings later and I still have to go over the whole thing with sacking mix.

Keith


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## John J (Dec 29, 2007)

hey Guys those are some great arch bridges. They look great.


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## jlyans (Jan 2, 2008)

This stone viaduct was built for a temporary layout at the Ventura, California, County Fair in 1991 by members of the Gold Coast Garden Railway Society. Peter Dwan made the concrete castings. You can see that the upper pieces of the viaduct are separate and each casting forms a half of the arch. The rectangular pillars are separate castings. They are joined together with mortar and the structure was very strong. Shown here under construction and before the landscaping and plants were installed, the layout was torn apart after the ten day fair. This was our third and final fair layout. That's my Delton C-16 testing the bridge. John Lyans


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## coyote97 (Apr 5, 2009)

Very well done Guys! 

Allowing myself to give a favorite: 
Keiths bridge is one of the best structures ive ever seen. 
On Johns pics the surface of the stoneswall is a BIT too rough, though the bridges are looking great. 

Greetings 

Frank


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## SE18 (Feb 21, 2008)

You guys have done a tremendous job with the concrete arches. Interesting to see the various techniques used. If I ever do another one, I'll borrow and steal some of your ideas. KUDOS to all!


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## George Schreyer (Jan 16, 2009)

I built a baby one with another technique 

http://www.girr.org/girr/tips/tips7/wonderboard_tips.html#bridge


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## SE18 (Feb 21, 2008)

Nice techniques, George, 

I'm saving some for my files; thanks


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## msimpson (Jan 5, 2009)

If you peruse back issues of Garden Railways and Sixteen Millimeter Today, you will find several similar articles -- No criticism meant of any of the fine efforts shown here. Some very nice work! 

Regards, Mike


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## SE18 (Feb 21, 2008)

There's a GR article run about 20 years ago that showed concrete forms with rebar sticking out the end. IMO this can lead to problems; rust, expansion, cracking. I've experienced that as has Marc, the editor. 

Not everything you read/see in GR is foolproof


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## Cougar Rock Rail (Jan 2, 2008)

There have also been a series of great articles in the German Gartenbahnprofi magazine which you can order--it really isn't necessary to be able to read the German to get the methodology and ideas etc. Some of the elaborate systems for doing things like the spiral Brusio viaduct are incredible! I like seeing how others do things too because sharing ideas is what moves this hobby forward and make it that much more interesting. 

Keith


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## CapeCodSteam (Jan 2, 2008)

Kieth, 

We really like your design, it is simular to our vision. Any additional information, details or discoveries would be most appreciated


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## Cougar Rock Rail (Jan 2, 2008)

Hi Kent,
Glad you like our viaduct! On the weekend I went over it with some sacking mix, to fill all the air voids left from the mix being a little on the dry side etc.
Below is a picture after that was done. Other than that, I'm sorry I don't have any drawings. I really do need to improve my documentation skills! Hopefully you can piece it together from the pictures.


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## CapeCodSteam (Jan 2, 2008)

No worries Kieth, 

Between your pictures and the others, Doug and I are now armed with enough information to be classified in the "dangerous" catagory


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## CapeCodSteam (Jan 2, 2008)

Well, the viaduct is done. We closed it up a bit and wound up with an eight foot span. Doug made a form for the deck using plywood and sonna tubes, cast two pieces and placed them together on top of cement blocks for the supports. All in all, it came out great.










Thanks again to everyone for their assistance


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## bottino (Feb 7, 2008)

Wow I guess that answers the original question. Awesome bridges guys.
Paul


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