How much tamping required for a culvert?

[Tractor Seabee]

Well it's in, burried & driveable. The 2 buckets of pea gravel made for easy packing around the pipe & not really any tamping. I tamped by for & tire in 6" lifts or so over the top. I failed to crush the pipe driving over it with only 6" of cover.

I'm sure it will be settling for a few years, but I grade the driveway a couple times a year anyway. Need to get a couple truck loads of gravel on it anyway. Also need to sculpt the inlet & outlet a bit. Also re-grade my shop driveway & get water running down the other side & towards the new culvert.

Will try & get photos in the morning if it's not snowing.

Remember; pea gravel around the pipe requires constraint on the ends (some kind of headwall) to prevent it from rolling out the ends when pressure is applied to the top. It also will push into surrounding soil as pressure is applied vertically. Pea gravel is just a bunch of ball bearings.It is normally used to backfill when the sharp edges of crushed aggregate may damage the pipe or tank it surrounds. Advantage: When constrained it is self compacting as there is nothing to fill the voids. Water will filter the covering materials down into it if not compacted crushed material.

Ron

 

[Fallon]

Remember; pea gravel around the pipe requires constraint on the ends (some kind of headwall) to prevent it from rolling out the ends when pressure is applied to the top. It also will push into surrounding soil as pressure is applied vertically. Pea gravel is just a bunch of ball bearings.It is normally used to backfill when the sharp edges of crushed aggregate may damage the pipe or tank it surrounds. Advantage: When constrained it is self compacting as there is nothing to fill the voids. Water will filter the covering materials down into it if not compacted crushed material.

Ron

Ya, I put dirt at the ends so the pea gravel won't squish out. The pea gravel only goes half to 3/4 of the way up the pipe. It was nice to see It just slide under the pipe to fully support it on the bottom. We lifted the pipe in a couple spots to keep it a half bubble off level. Pea gravel instantly filled any potential voids. I'm sure it will cause worse settling issues long term as dirt migrates into the voids as well as the normal settling. I have the box blade to deal with the reoccurring digit though.

 

[Egon]

Here's how mine was installed in April 2005. Professional job. No problems.

/QUOTE]

Excellent!!! I want to pave my driveway so bad......

Better wait till it finishes settling!

 

[ovrszd]

Better wait till it finishes settling!

Can't figure out who you are quoting..... My driveway is long past settling...

 

[flusher]

Better wait till it finishes settling!

Yep. The paving was done about 8 months after the driveway was installed. The county gives you time for settling before completing the paved driveway connection to the county road. The connection is only about 25 feet long per the building code.

 

[kevin37b]

A culvert needs non settling backfill at least halfway up the side of the pipe . This is called the haunch of the pipe be it round or oval . The n12 double wall plastic is quite strong in this app. Cover is not the main concern . I can set a backhoe bucket in the middle of a 20 ft piece of 12, 18 , and not crush it with it in a parking lot . However it seems whatever you post anymore there is always a better idea . K evin .

 

[ovrszd]

A culvert needs non settling backfill at least halfway up the side of the pipe . This is called the haunch of the pipe be it round or oval . The n12 double wall plastic is quite strong in this app. Cover is not the main concern . I can set a backhoe bucket in the middle of a 20 ft piece of 12, 18 , and not crush it with it in a parking lot . However it seems whatever you post anymore there is always a better idea . K evin .

I'm a "do what works for you" guy.

 

[Fallon]

Finally got a photo.




Need to taper the entrance & exit of the culvert across the main driveway a bit, but otherwise it's in. Need to re-grade the driveway up to my shop (behind the trees) so it slopes away from the house & towards the culvert as well as putting in a bit of a ditch on that side. That will most likely happen when I get some spare cash for a few dumptruck loads of gravel for everything. Also need to scrape off the gravel infront of the house & remove 6-8" of driveway to do a better job re-grading (did a patch job shortly after we moved in so it drained a bit).

 

[ovrszd]

Thanks for the pics!!!

I deal with situations similar to this frequently. Land owners will ask me to install a culvert for a driveway or gateway. When I begin telling them what I'm going to do they sometimes get reluctant. They struggle to understand that if a 15" diameter culvert is installed it will require a ditch 20" deep. "Oh my, I don't want a ditch to mow"!!!

 

[jejeosborne]

I had a Culvert fail after 6 years because it was improperly installed by my contractor. It was a 15 inch buried about 6 feet under my drive where it crosses a Ravine. The weight of the soil and the traffic collapsed the double wall pipe. Plastic pipe is much more critical to properly install. Mine was difficult to replace because my primary electric, water and cable was all above the pipe.