# Switch and Yard Foundations



## CliffyJ (Apr 29, 2009)

Hi again, 

I was wondering if it was standard practice to lay sections of concrete backer board (the sort used in tiled bathrooms) in the roadbed, in certain critical sections of track.


First area of question is switch foundations. Per a great conversation with Axel at Train Li, for servicing / removal, I’d like to plant my switches on removable concrete backer board. In regards to a PVC roadbed substructure with foam roadbed (I just posted on this subject), I picture this material being substituted for the foam in switch areas. Has anyone experimented with this sort of thing (with or without the PVC substructure)?


Second area of question is yards. Backer board seems a great way to keep an entire yard level, without resorting to individual trenches / etc. But I can imagine voids in the soil / gravel opening up beneath (due to settling), presenting risk areas for cracking if one were to step on them. Does anyone have advice on this?


Thanks in advance for any insights, or other threads / articles you can point me to,


===Cliff


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## CliffyJ (Apr 29, 2009)

Thinking about it more, I guess concrete board for a yard won't work, due to frost heave... unless you set it on well-sunk posts with a subframe, like a table top... But maybe that's worth it?


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## NTCGRR (Jan 2, 2008)

How big of "yards" are you talking ? I personally like concrete.


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## John J (Dec 29, 2007)

Me too I like concrete 
JJ


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## CliffyJ (Apr 29, 2009)

Nice!

Is that a formed / poured roadbed, or the "backer board" I was talking about?
In the distance, it looks like you use concrete for "regular" roadbed, is that so?

I've often wondered why the Brits seem to favor concrete, but not us Yanks. 
What's the downside of doing all-concrete roadbed? Seems a lot cheaper and (if certain rules are followed) stable.

Cliff


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## JackM (Jul 29, 2008)

What's the downside of doing all-concrete roadbed? 

POTHOLES!! The ol' freeze/thaw cycle. It's gonna crack and shift and do all sorts of amazing gyrations. Unless you're down South, in which case have a nice day. 

JackM


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## Totalwrecker (Feb 26, 2009)

You had better have the perfect layout plan when you start pouring crete...my railroad has grown in different directions from the start. 
Much easier to shovel ballast into a bucket than to relay concrete.








Of ciourse the old non-used sections can become hiking trails.... 

I have a roundy, I've decided I'd rather have a loop to loop linear RR...at least there won't be crete to bust up. 
Finally it's best used by home-owners, can't imagine a landlord wishing for ribbons of crete in his yard.









Other than that it is very stable. 

John


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## CliffyJ (Apr 29, 2009)

10-4 John. I've been tweaking my plan for over 1.5 years (during the excavation / retaining wall / deck building phases), and it's stable. So, I have great confidence in the plan, which I fully expect to last at least until the day I begin pouring concrete. 

What I'm interested in understanding (bear with me, I an a total newB) is the general viability of concrete roadbed. Jack, you say that it will heave up and down with the frost, which is the reason I abandoned the whole approach. On the other hand, a bunch of books I have say that it's a valid approach, and it's clear that our cohorts across the pond use the method quite liberally (and I think it gets cold in England, from what I've been seeing on the news at least!). 

So, here's the problem I'd like you folks to solve, or at least opine on, for me: 
Given: a certain section of layout (e.g., a central, small yard and it's lead-in trackage) has a plan that is solid and won't change 
Given: everything else hinges on this area's accurate geometry 
Given: frost heave will be in effect 
Given: some people have obviously figured it out, but I can't find any details on whether it holds up (even the late Peter Jones in Practical Garden Railways didn't really elaborate much on this) 
Given: I've seen no published details on how to make a concrete method work under conditions I've described -- unless it's just as simple as it seems, and further detail just isn't needed. 
Hypothesis: that a concrete solution will be cheaper and at least as stable as a ladder or gravel-in-trench method 
Problem: to make it stable, heave-proof, crack-proof, pothole-proof, 
- What would be the proper depth and width? 
- How best to reinforce? 
- In yards, is it best to just pour a slab? 
- Or can I just use concrete backer-board (ref. my original questions)? If so, how to support? 

Sorry for being a weenie, it's just that many thousands of bucks have been spent on the prep work, and thousands more will be spent on the track, and I'm just not comfortable at all with my current notions of how to go forward with the roadbed. Some days, gravel-in-trench seems best, other days cedar ladder, now PVC ladder, now back again to concrete... 

The frustating thing for me is that no matter what method, there are always experienced voices saying that all heck will break loose if I go that way, that they tore it up and went with X method and now they're happy. Arrgh! 

I guess I'm just a wuss, but I really don't want to blow this. I need a main method to go with, and I need it to last for at least 10 years. OK, I get it that one will need to do maintenance, work the layout, etc. But what I don't want to mess up on is choosing a roadbed method that doesn't best accommodate the conditions, but instead invites instability. 

Thanks for putting up with all my questions, and any insights are more than welcome. 

===CliffyJ in Maryland


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## TrotFox (Feb 15, 2008)

Cliffy, 

Each method has merit and each one will perform better in a different part of the country. Why not build the layout in sections and try the methods you believe are best suited to your environment? When one fails you can perform a root-cause analisys and figure out which one is better for you. That way you minimize future repair work and figure out which method is for you.  

Just a thought! 
Trot, the piecemeal, fox...


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## CliffyJ (Apr 29, 2009)

Wise advice indeed, Fox. 

If I were to apply it, I'd avoid anything I can't easily dismantle, and that means concrete roadbed. 

You hit the nail on the head. 

And I like the idea of a root cause analysis. You were maybe joking, but I'd really love to see an in-depth failure analisis of various roadbed approaches, factored for climate, price per foot, appearance, ease of construction and maintainability, and so on. The books I have seem to say, 'well, some people do it this way, others that way..." without any detailed examination on what to expect. Short of such an analysis, it would be great to see what people vote for, vs. climate zone, and how much it cost per foot -- like a simple poll. Either way, such a comparative review would be very instructive to newbies like me!









Thanks,
Cliff


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## Terl (Jan 2, 2008)

The members of the Ottawa Valley Railway Society seem pretty happy putting track on treated wooden planks. Don't screw through the ties to hold the track in place. It is better to use an short piece of iron wire fastened to a screw between the ties, which is then bent over the ties. This gives you some important expansion and adjustment room. This fastening method was pioneered by JJ 
. 
Terl


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## Rod Fearnley (Jan 2, 2008)

"I've often wondered why the Brits seem to favor concrete, but not us Yanks." 
Spend a winter , spring over here Cliff, and that should show you your answer as to why.







Wet wet wet.

I laid some backer board which at the time was great and looked good. Over two years it became water logged and frost damaged. So I reverted to concrete.
Rod


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## TrotFox (Feb 15, 2008)

Cliff, 

Well don't look at me. I've had track on the ground exactly once in the last 15 years. That was simply laid on smoothed earth and ballasted as I was in a rental house. When our landlord turned out to be a kidnapper and crook we were booted from the place and that track was quickly pulled up. I started to build a concrete roadbed which was going to double as garden-edgeing at the first house I owned but the going was extremely slow without the right tools and it never even saw trackage. Mostly I've been too buzy with school or other life activities to devote much time to trains. When I do get time for the trains I tend to be loazy and check out this forum. :] 

Now I'm in an apartment, running on a museum layout which is a raised-bed construction with ballast. We relevel from time to time but mostly it deals with the E-TN climate acceptably.  

Later, 
Trot, the inexperienced, fox...


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## Manco (Jan 5, 2009)

Don't be scared away from considering concrete. With reinforcement IE: 3/8" strand of rebar running down the center of your pour, it distributes the forces of heaving enough that cracking should for the most part be eliminated. Marty has used it successfully for years and it gets cold at his house. I poured some ribbon roadbed with reinforcement last summer. The ground has been frozen for several weeks now and I keep going out to check... no cracks. At this point last year, my PVC ladder roadbed had heaved into a roller coaster. So far so good.


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## Totalwrecker (Feb 26, 2009)

The trick to using rebar is to keep it fully encapsulated by concrete and absolutelty none sticking into the dirt below. Use stones or broken bits of crete to hold it off the ground. Use the wire to secure rebar to rebar at switches. Make sure your wire ends don't poke the ground below nor extend higher than your pour. 
Rust is oxidation, steel is dense to add oxygen it grows and causes cracks, which lets in more water and so it goes. The heat of the cure drives out internal moisture and preserves the rebar, as long as you don't let water in. Don't skimp on the cover thickness. Too thin and an errant foot might crack it. Your local codes for a sidewalk should be a good starting point. 

John


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## CliffyJ (Apr 29, 2009)

"Spend a winter , spring over here Cliff, and that should show you your answer as to why.







Wet wet wet."

That's what I figured, Rod, thanks for the reply. So how do you reinforce it, and to what depth is your 'crete? Do you have any frost heave issues that might buckle and crumble the whole thing?

Also, how does one dress the top surface to look like a ballasted shortline instead of a Euro-rail mainline?

Cliff


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## CliffyJ (Apr 29, 2009)

Posted By Manco on 11 Jan 2011 04:31 PM 
Don't be scared away from considering concrete. With reinforcement IE: 3/8" strand of rebar running down the center of your pour, it distributes the forces of heaving enough that cracking should for the most part be eliminated. Marty has used it successfully for years and it gets cold at his house. I poured some ribbon roadbed with reinforcement last summer. The ground has been frozen for several weeks now and I keep going out to check... no cracks. At this point last year, my PVC ladder roadbed had heaved into a roller coaster. So far so good. 
That's a mouthful. You've given a simple answer as to method and performance, Manco. You've also confirmed what I've been worried about, re. PVC ladder roadbed. 

Maybe I missed something obvious, but could you point me toward Marty's layout info, specifically, his method and location? Also, in what regoin do you live?

Thank you sir,

Cliff


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## CliffyJ (Apr 29, 2009)

Thanks John, you present specific info, and make clear the need for encasement. It all makes sense, and helps take the voodoo out of it. 

After all, if one were to form up and reinforce for a concrete curb, that would be it. That is, if a car could drive over it, it would break and crumble just because a train rode over it, right? (Sheesh, I'm so worn out psyching myself out: per all the articles and post and dire warnings I've read over the months, it almost seems as if the G-gauge loco is the perfect weapon, guaranteed to wipe out anything it traverses...







). Forgive me my joke though: I take very seriously all the stories and experiences conveyed here and elsewhere on these matters, and I'm only speaking from a standpoint of budgetarily-concerned-frustrated-ignorance. 

But happy, I LOVE THIS HOBBY! 

OK though, let's talk specifics. And instead of questions, I'll put out a tentative-theoretical concrete approach, and please point out the flaws, or at least your different thoughts:

0. Assume soil is well compacted (but undulating)
1. Survey and stake track centerline with rebar posts, and mark elevations
2. Place centerline ribbon of 1/2" x 3-1/2" plastic board and adjust elevations / curvature (wire to stakes) (


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## Totalwrecker (Feb 26, 2009)

Posted By CliffyJ on 11 Jan 2011 07:41 PM 
Thanks John, you present specific info, and mad clear the need for encasement. It all makes sense, and helps take the voodoo out of it. 

After all, if one were to form up and reinforce for a concrete curb, that would be it. That is, if a car could drive over it, it would break and crumble just because a G-gauge loco rode over it, right? (Sheesh, I'm so worn out psyching myself out, with all the articles and post and dire warnings I've read over the months, no matter what the method...







)

OK though, let's talk specifics. And instead of questions, I'll put out a tentative approach, and please point out the flaws, or at least your different experiences:

1. Survey, stake and mark elevations with rebar posts
2. Place centerline ribbon of plastic board
3. Where soil is too low, form up to either side of centerline and build up soil to support and compact
4. Where soil is too high, trench
5. Ensure 6" concrete depth and width (


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## wigginsn (Jan 9, 2008)

Here's a link to an article on making concrete roadbed in the MLS archives, by Marty C.


*http://archive.mylargescale.com/articles/articles/concreteroadbed/roadbed01.asp*

Happy reading. I did a small stretch as a test a couple of years ago and am considering it for the last section of the layout that I need to build. Wasn't hard to put together, and a 10 lb sledge hammer will remove it in a very short time if reqd..

Cheers
Neil


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## SE18 (Feb 21, 2008)

The most common mistake I see on this forum is people ignoring the advice to keep steel rebar well inside the concrete to keep it from rusting and expanding. People just won't listen to this advice. The cracking will come, believe me. I'd say it must be 4 inches embedded in concrete. 2" minimum but even that might be pushing it as concrete is fairly porous. 

I've laid concrete roadbed and had no trouble later relocating it. A sledge and hammer drill and some muscle is all that's needed. If you don't have muscle, join a gym. It will do you good. 

Dave


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## Paul Burch (Jan 2, 2008)

I'm a fan of concrete. My oldest pour has been down about 6 years now without any failures. About 2.5 inches thick with a single piece of rebar down the middle leaving an end sticking out to tie to the next section. I use the high strenght stuff from Home Depot. Temperatures here in this area of the Northwest can range from upper teens (rare) to 90's in the summer with lots of winter moisture.


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## John J (Dec 29, 2007)

Posted By SE18 on 13 Jan 2011 06:42 AM 
The most common mistake I see on this forum is people ignoring the advice to keep steel rebar well inside the concrete to keep it from rusting and expanding. People just won't listen to this advice. The cracking will come, believe me. I'd say it must be 4 inches embedded in concrete. 2" minimum but even that might be pushing it as concrete is fairly porous. 

I've laid concrete roadbed and had no trouble later relocating it. A sledge and hammer drill and some muscle is all that's needed. If you don't have muscle, join a gym. It will do you good. 

Dave 

Amen and Amen.

The NR&W is in it'sd 12 th year. All the pictures I have posted show you concrete is that is about 12 year sold. I buildt the tunnesl around it I put all the rocks around it. Some of the canyons lget 5 inches of water rushing down them. 

I never have to check side to side level. Just run after I cleared some debris from the track. 

Ops I better add this.....Except for the 20 FT around Carters canyon where work is concentrated now. 

JJ


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## CliffyJ (Apr 29, 2009)

Thanks for that link Neil, great article. It looks so straightforward, and stable...


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## jake3404 (Dec 3, 2010)

I believe that concrete is probably the most permanent method. I also believe it will withstand frost heave the most effective. However, be prepared to have frost heave at times during the life of the railroad. Concrete isnt bulletproof. 

Along with the advice about rebar touching the ground, I would add that concrete will definately crack, it is inevitable, however, if you keep an eye out for cracks and then seal them with a good sealer. You will have a roadbed that will last much longer and less likely to heave.


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