Colvert???

[PBMAX]

Hey all,Somebodys been busy...While I was gone...Looks nice...

What I need is howmuch churt should I use over the colvert (driveway pipe) for support before I put down gravel and concrete...?It is a 12" round pipe and is 20' in length...I'd also like to add on 10' more to have 30' wide (to span out for turning in and out )so as to have about 25' of concrete with out getting close to the end to ruduce the amount of stress cracks that can pop up over the years for various reasons...Any ideas???

Lil' Paul

Laziness is the Father of invention.../w3tcompact/icons/laugh.gif

 

[roysallis]

Paul,
What kind of pipe do you have? If you are using plastic they are pretty strong but I would put about a foot of churt. Metal pipes should not need that much. Go look and the culverts the county has put in for driveways and see how much churt/dirt they use.

 

[Bird]

I sure learn a lot of new words on this forum./w3tcompact/icons/laugh.gif When I saw your spelling of what I always called a "culvert", it reminded me of the fact that folks in this area call them a "horn"; a term I'd never heard used for driveway pipe until 6 years ago, and still don't know where it orginated. And what is "churt"? I never heard that before and don't find it in either of my dictionaries. I've got 3 culverts, each about 20' long, but different diameters; 6", 12" and 20" I believe, and I don't think any of them have more than 6" of dirt on top and I've never had any problems with them, but they're all concrete pipe instead of the metal that's more commonly used in this area now.

Bird

 

[Jag]

PB - I have a closed cell corragated plastic 18" pipe about 20 foot long, with a less than a foot of good back fill over it. Been in the ground little over an year now in an old field road. The lack of fill is due to location. I just had timber cut and one or two trucks that came out with over 90,000 pounds. Not sure what the axel weight would be, but it is sure more than most drives will see. Would guess that maybe twenty loaded trucks came out plus the timber equipment. Just cleaned out one end of the pipe this morning, where they drug some limbs and topsoil into the ditch. The pipe looks great. I really can reccommend it.

 

[EddieW]

Paul, I have a 30' by 18" "tin horn" as we call them here. It is made of rolled corrugated steel. It cost $240. THe county installs all culverts for free that are within county road easements so us dummies don't create maintenance problems for them. THey put clay around it then covered the top with about 6" of 3/4 inch crushed rock. I had 4" of concrete put on top of that for my driveway. It has been there three years and has had cement trucks, moving vans, a caterpillar and 14 yard dump trucks go over it with no impact.

 

[Thomas]

Paul,
Over the years I used nothing but metal culverts,but after useing the plastic culverts I'm impress. /w3tcompact/icons/shocked.gif
The plastic culverts are tough easy to handle also one can bend them a little plus easy to add on.

How far do you plan to set the culvert into the ground?
I just use good fill and packed it well and no problems yet./w3tcompact/icons/smile.gif

Have a great weekend and stay safe and /w3tcompact/icons/cool.gif

Thomas..NH

 

[W5FL]

Paul, here the county installs the culverts if they are on a road. They charge only for materials. Mine is a total of 32 feet long. The last 4 feet are concrete pipe and the center is metal (24 ft). This keeps the end from getting crushed when some truck runs off the end. Cover here is minimal about 4 to 6 inches. If you are going to pave over it, be sure to let it settle through a few rains first.

 

[EddieW]

Thomas, do you know what the plastic pipe costs in either 18" or 24" diameter? I'm thinking of putting in a drain to bypass a shop I'm building and sure looking to save any money I can. OF course, it may never rain here again so water may not be a problem. /w3tcompact/icons/frown.gif

 

[Kelvin]

For PBurns, EddieW and everyone else:

I did some brief comparisons last summer on the different culverts. I believe that this is good information, but nonetheless it is a collection of "opinions" that are worth checking into further.

Supposedly, the new plastic culverts are about half the price of the metal ones, and just a durable (possibly more so). They have the corrugated outside but have a smooth inside so as to allow easier water flow without debris hangup. According to various sources the plastic pipe was slow to catch on initially but was starting to gain a lot of momentum as it proved itself.

How much fill? I was told that regardless of construction that there needed to be at least one foot (minimum) of fill dirt used on top of the culvert to distribute the loads. I've seen metal culverts (estimated to have 6 inches of dirt/gravel coverage) at ball parks cave in with rare vehicle traffic and a compact tractor.

If anyone has information contrary to what I've posted here please be sure and speak up. I've put off building till next year but will eventually be investing in some culverts.

 

[Harv]

Can't remember where I originally found this, but I think it was from some official highway construction guidline document --

"Bedding and Backfilling: Stumps, rocks, frozen lumps, and other debris should be removed from the bedding site. Well graded drainable backfill is recommended for good compaction. The designer should refer to the gradation and backfill specifications of the appropriate provincial highway standards.

Round pipe can be built on a flat sand cushion with rodding and tamping of the backfill around the haunches. Alternatively, the pipe can be installed on a pre-shaped granular base.

Backfill should be spread in 150 mm layers alternating from one side of the pipe to the other, and should extend above the pipe to a minimum height of 300 mm or one sixth the span, whichever is greater."

Note that 300mm is pretty close to a foot, just like I keep hearing everywhere. Think there's a message here? /w3tcompact/icons/smile.gif