Attaching 36'' Plastic Culverts

[Doxiegals]

I'm a new b so play nice!

Recently I discovered the 36'' plastic culvert under my driveway was crushed down to about 6''.For the last 4 years in the spring I would have to drag rock from my drive to fill in on top of the culvert because of settling. I had approx. 200' of 36'' plastic culvert burried across my lot about 25 years ago. I now know that it was not installed properly as the culverts were just backfilled with black dirt, clay or whatever was handy at the time and none of it was compacted thus the failure.
So I hired a local company that I have used in the past ( Super Guy ) to dig it up. Keep in mind this 20' culvert is approx. in the middle of the 200' span of culverts. When we dug the damaged culvert out we found it had a what I will call a Spiral ribbed outside for support. The new one had a straight rib outside and singular in design. ( Not Connected ) Does anyone know what the procedure is to connect a spiral to a straight culvert would be?
We were forced to use the straight connecting bands that came with the new culvert to the spiral culverts. (which didn't match worth a crap) We laid 1/4'' belting material above the culvert at the connectors on top of the ribs where it did not seal,hoping that after using a compactor with class 5 material around and on top would help seal it? We were told the spiral culvert was no longer available.
I am worried that come spring thawing or heavy rains it will leak and eat out alond side of the culvert causing a wash out or sink hole.
I would appreciate any advice on what should have been done as well as what to do if it fails again.
Thanks,
Steve

 

[Kyle_in_Tex]

Wow, I have no idea. But it sounds like you did your best. Maybe it will hold?

Did you ask the mfg how much it would hold?

 

[Kyle_in_Tex]

Oh and welcome aboard. Most everyone here is friendly. No cussing, etc.

 

[Streetcar]

The other alternative is concrete collar to encase the joint. I have done this for mismatched pipes
Welcome to tbn

 

[CNC Dan]

I would get the two pieces lined up best I could and fill any gaps with spray foam.

 

[CurlyDave]

The other alternative is concrete collar to encase the joint. I have done this for mismatched pipes
Welcome to tbn

That is the way I would recommend doing it. A concrete footer and "half-pipe" formed up and poured underneath each joint, and then then a "cap" poured on the upper half once the footer had cured.

 

[Doxiegals]

Thanks for your help. Hopefully I don't need it!!!

 

[Coyote machine]

Welcome too to TBN.
36" spiral no longer available?! That sounds wrong to me. I just had my town, I guess that's what they're called , replace two 20' sections of exactly that, spiral with smooth inside, (referred to as double wall), at the ROW/across the town road, at my flip property this past summer.
They said nothing about it being scarce. It was used to replace disintegrated metal from a thousand years before the dinosaurs. They took off the end coverings, ( each section has a male and female end for joining), and slapped copious amounts of a grease of some sort on it and mated the female to male end, then covered it with stone/fill dead muskrats, etc., done.

Here's a link to just one of many suppliers of the type of pipe you need:

Request Rejected

I would look into the situation carefully and if you can get matching pipe to what's already in the ground repair it properly with the same stuff. Otherwise you'll continue to have issues down the road. JMHO:thumbsup:

 

[ovrszd]

Don't worry about the different spirals and a tight connection.

The problem you had was caused by digging a narrow trench to put the original culvert into. Fill material could not get under the bottom half of the culvert. So it created a vacancy that eventually filled itself. It did so by crushing the culvert.

Never bury a culvert in a tight fitting trench. Always have at least 50% of the culvert width of open trench on each side. So for a 36" culvert you needed at least a 72" trench. This allows fill material to be place under the bottom half of the culvert. Even with this situation you will still see some "egg shaping" of the culvert. But it won't affect the volume flow of the culvert.

Fill material is irrelevant. I never use anything but dirt.

I work for a Township and over the past 25 years have buried hundreds of road culverts. I've never used special fill material. I always want an open trench so I can get material under the culvert. Once I get some under it, I pack the snot out of it with the Road Grader. It will always settle. You can't stop that. Just expect it.

Good luck with your project.

 

[ovrszd]

Don't worry about the different spirals and a tight connection.

The problem you had was caused by digging a narrow trench to put the original culvert into. Fill material could not get under the bottom half of the culvert. So it created a vacancy that eventually filled itself. It did so by crushing the culvert.

Never bury a culvert in a tight fitting trench. Always have at least 50% of the culvert width of open trench on each side. So for a 36" culvert you needed at least a 72" trench. This allows fill material to be place under the bottom half of the culvert. Even with this situation you will still see some "egg shaping" of the culvert. But it won't affect the volume flow of the culvert.

Fill material is irrelevant. I never use anything but dirt.

I work for a Township and over the past 25 years have buried hundreds of road culverts. I've never used special fill material. I always want an open trench so I can get material under the culvert. Once I get some under it, I pack the snot out of it with the Road Grader. It will always settle. You can't stop that. Just expect it.

Good luck with your project.