# Formula for # of Bags of Concrete



## johnnyboy (Jan 25, 2008)

I think one of the big questions, I know it is for me, is how many bags of concrete, premixed, am I going to need to pour my roadbed.  I found this formula, link below, it seems correct but if anyone can give me their opinion that would be great.  Also how deep should I go with the concrete, I heard 1 1/2" to 2". 

Thanks,

Johnny

ezinearticles.com/


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## Torby (Jan 2, 2008)

Not a contractor, but those figures look right. 

Marty pours his 2 inches and puts 3/8 rebar in them. He's a contractor, so I think I'd take his advice. He's sure to chime in here shortly.


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## NTCGRR (Jan 2, 2008)

1 bag mortar mix with 2 bags gravel mix.

2" is fine over none fill areas. I you have compacked a deeper fill then I'd go thicker, 3"

omly make it the wideth of the ties. more is not better in this case.  Plus I started using black powdered dye just to take away the "lightness" of it.

3/8 rebar, over lap and tie together at ends and switches. top does not have to be perfectly smooth, just level with no lumps.

get about 15ft per mix, easier to use wheel barrel and have it at the site, VS a mixer and carring the heavy stuff over.


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## Torby (Jan 2, 2008)

Wonder when your how to will reappear under "articles."


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## johnnyboy (Jan 25, 2008)

Thanks Marty 

Johnny


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## John J (Dec 29, 2007)

All my  Concrete road bed is  aminamum of  2 inches   some of it is more. up to  3 inch in some places.

There is  another thread  in here  about  concrete road bed that I have posted pictures.   That should help you


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## Ward H (Jan 5, 2008)

Marty, John, 
I am planning on going with cement roadbed for an expansion this spring. I need to run a loop to my shed and back to my layout. About 20 feet wiill be across the yard. How do you tie the track to the cement roadbed? Have you experianced running things across it like wheelbarrows and lawnmowers? Does the track hold up? 

Was thinking about laying a piece in the driverway and doing some durability test on it to see how well it holds up. I use all Aristo brass track.


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## Madman (Jan 5, 2008)

*If you are buying premixed concrete in baggs, like Sakrete or Quikcrete, the formula is as follows. 

80# bags will yield about 2/3 of a cubic foot per bag.

60# bags will yield 1/2 of a cubic foot per bag.*


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## John J (Dec 29, 2007)

I use the regualr 80 lb bags of  concrete where you just add water.

I have removable sections  to get the  tractor accross.    The track will not stan up to things running accross it

How ever!!!!!!!!!!!!!  Stan Cederleaf   "MADE"  track accross his driveway  that he drove his car over.    

Contact him for some pictures.

To anchor my track I use   1/4 inch plastic anchors.   They are blue.  You can  get them by the box at  Home  Depot.

I drill a  1/4  inch hole,  insert the plastic  anchor.   I then  use a  Piece of   Wire  with a loop in the middle for the screw.

I  insert the screw in the anchor and bend the wire over the ties.

I use the  same wire they use to  wire  Re Bar together.  It is stiff but flex able.   

I have some  pics on here somewhere    I will  add them to this thread later.


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## SE18 (Feb 21, 2008)

always get more bags than you need; otherwise you will surely get screwed when you run out


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## rpc7271 (Jan 2, 2008)

As for anchoring track to the concrete, I use LGB track and use GE Silicon II silicon caulking. I fill the underside of the tie full plus a little extra. Fill a tie every 8 inches or so and then place the track. I use spare bricks on top to hold the track in place for about 24 hours until the caulking cures. It holds the track in place but allows a little movement when the track expands or contracts. Kinda having a little rubber buffer between the track and concrete. I have track that has been out in the Arizona sun and cold (and yes it does get cold in Arizona) for over 4 years and it is still solid in place. One word of caution though: take expansion of the rails into consideration. I usually place track only when it is above 110 deegrees that way the rail can only contract. If I do place track when it is cooler I need to leave small expansion "Gaps" every 2 sections or so. Make sure you get it right the first time because it is almost impossible to get up if you need to change something.


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## Torby (Jan 2, 2008)

Always buy more material than you'll need. It's a lot less annoying to take some extra back than to run back in the middle of the project for more.

Of course, doing a wiring job on one of Susan's projects, she kept complaining, "50 ft should be more than enough!" She didn't understand the distances involved. Altogether, that project was 1,200 ft.


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## NTCGRR (Jan 2, 2008)

All they have here is 60 pd bags of each. 
Ward 
This past year I started removing the screws from under the ties. this allows me to anker the ties down and still let the rail free float. if in full sun I grid exspantion joints every 20 fr or so. 

I rip cedar and screw it down on each side of the track and a thin piece in the middle where folks walk or wheel barrols go over. 
kinda like a grade crossing,


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## pimanjc (Jan 2, 2008)

When I first started pouring concrete roadway, I used 80lb bags [Marty's mix ratio].  I now only get the lighter bags [more of them ] to do the job.  It is much easier on my flakey back.  

I haven't spoken up earlier in this thread because I didn't have anything useful to add.  All I know and have tried, was taught by Marty, and he had described how he does his roadbed.   

One bit of encouragement to anyone trying to lay concrete roadbed:   The first 15ft poured, took me almost two days to form, rebar, pour and finish.  By the 4th or 5th section, only about  2 1/2 hours from start to finish were required.  

Jim Carter


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## John J (Dec 29, 2007)

Home Depot sells this  stuff that looks like  MASONITE.   It is Tan and smooth and  is aobut  1/4 inch thick by  2 ,5 inces wide.  It is not that expantion joint stuff.  This is more dense.   It is great for makeing forms especially   curves as it bends easily.   Plus it can be re used.  

I will stop by home depot today and see if I can get a  skeu  number.\


Here is how I anchor my track 










The wire is  the stuff  they use to  tie rebar together.  You can get it at Home Depot in a spool
It is cheap.

I drill a 1/4 in hole in the concrete road bed and insert the plastic anchor.

I bend a loop in a short piced of wire  to fit around the screw.   

Put the screw in the anchor and  tighten.

I then bend the wire over the  tie.

It holds pretty tight

Some times  I take a longer piece of wire  and make the loop in the middle for the screw   

Then I bed it  over  to  ties   one on each side of the  anchor.


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## Madman (Jan 5, 2008)

That's an excellent idea for anchoring to concrete roadbed.


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