PVC toe drain

[sandman21ss]

I've been browsing online for a good website that lists PVC pipe types (EG. SDR 17) that measure up in accordance with particular ASTM standards (specifically F 949 and D 3034).

I've come across manufacturer's websites that have grids of their products and explain which standards they meet up to.
But does anyone have a good reference of a multitude of pipe types, or is it necessary to check pipes against the standards as I come across them?

Also, where could I find information in regards to design life of particular types of connection joints (cement vs gaskets)?

I'm a new EIT at a design firm and have been put to the task of coming up with a permanent toe drain solution for an embankment improvement. I'm not entirely sure of where to start. I've been researching a bit, but thought this may be of use as well.

 

[cvg]

you can download this and should be easy to find:

Technical Manual:
Plastic Pipe Used in Embankment Dams
Best Practices for Design, Construction, Problem Identification and
Evaluation, Inspection, Maintenance, Renovation, and Repair
November 2007
FEMA

 

[sandman21ss]

Manual is very helpful, thanks.

 

[sandman21ss]

Just to get some additional input, is HDPE or PVC preferred in this situation?

Perforated toe drain will be either 8" or 10" and approximately 5000 LF. Depth below surface is between 4-6 feet. The embankment is considered a high hazard potential. Causes of concern are expansion and contraction due to seasonal temperature changes causing cracking and joint leakage. Rigid joints are desirable.

I've been comparing corrugated HDPE vs PVC and other than the price, corrugated HDPE seems better in nearly every way, especially in durability with cold weather. This pipe won't be buried below the frost line.

 

[dgillette]

We've had some not-so-good experience with crushing of single-wall HDPE pipe (some of which may have found its way into that FEMA pub that CVG mentions). Nowadays I always spec smooth-interior double-wall HDPE for that sort of thing. So far, so good. I also spec bends made up of 22.5-degree elbows, so it's easier to get cleaning equipment (or occasionally even a video camera) through.

PVC is a lot more brittle.

Best regards,
DRG

 

[cvg]

I agree with Dave and in addition, pay careful attention to the grade of resin and ask for the higher grade. Not all HDPE is good quality, some is really lousy. Dave, what do you recommend for the joints? Have you allowed standard bell and spigot, or required couplers or butt fusion welded or something else?

 

[sandman21ss]

In regards to resin, the manual makes mention of AASHTO M252 and states that it makes environmental cracks basically obsolete. From your experience, is that standard sufficient?

Insight on joints would be much appreciated.

 

[dgillette]

We've generally used couplers, and I actually don't know about how well B&S would perform. In a dam toe drain, I can justify the additional cost of couplers by the safety implications of having a joint pull open due to settlement or construction traffic over it.

I've seen welding used for the solid HDPE pipes used to carry various liquids and slurries long distances around phosphate mines when I was in Florida. They always appeared to work well, but for a perf'd toe drain (which needs to be sand-tight, but not water-tight), I'm not sure there is any justification for that next increment of cost.

 

[cvg]

here is a spec I have used for the resins in the past:

Resins shall conform to the minimum requirements of cell classification 345464 C as defined and described in the latest version of ASTM D3350 “Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”.

 

[jgailla]

With only 4'-6' of fill, I would normally use SDR 26 PVC with gasketed joints unless there are other considerations.
HDPE is more difficult to install correctly because of the flexibility. PVC will be better if everything isn't backfilled exactly right.
The gasketed PVC is also easier to install correctly.

 

[dgillette]

The flexibility of HDPE shouldn't be an issue with DOUBLE-WALL pipe. (I just wouldn't use single-wall for an important drain, like for a dam.) Double-wall HDPE should handle just about like any other relatively rigid pipe, and I don't think PVC would actually be more robust against misalignment during backfill. Couplers on HDPE are, I believe, stronger than gasketed joints, reducing the chance for pull-apart, and on a slotted or perf'd pipe, there is no need for water tight joints.

 

[BigH]

If this is perforated drain pipe - why not follow the AASHTO material specification?

 

[cvg]

AASHTO 252 could be used for PE pipe drains, note that it references a lower cell classification for the resin and only goes to 10 inch maximum. AASHTO also includes specs for various other types of perf pipe that probably should not be used