Flexible Connections between FRP MHs & ex. VCP sewer 1

[twise99]

Will specifying flexible neoprene boots on the stub out be sufficient? I am concerned about settlement of the existing pipe once the new FRP manhole is installed and backfilled. Anyone have any thoughts on this one?

Also, how to support the existng clay pipe during installation of FRP manhole???

Thanks!

 

[cvg]

why would the existing pipe settle? Presumably it has been in place for a while and the settlement has already occurred. Neoprene boot is still a good idea.

 

[LHA]

I'd Spec a Doghouse Manhole, and pour a concrete base under the existing pipe. Then just break out the clay pipe once the MH is set. No stub-outs or connections required.

Make sure the FRP MH is available in Doghouse. If it is not, the cost savings on installation may well justify a concrete manhole.

Suppport will be an issue, though, as clay pipe (I think) is 4 or 5 foot sections. But, if you go with a poured base, you could just have a leadered note on the detail showing brick blocking under ex. VCP.

Remember: The Chinese ideogram for “crisis” is comprised of the characters for “danger” and “opportunity.”
-Steve