AC Pipe Abandonment in place
AC Pipe Abandonment in place
(OP)
We have an old AC water main (about 3000 LF) that we want to abandon in place with grout fill or flowable fill. We are aware of the friable nature and environmental hazards of AC pipe hence we don't want to to remove it. The grout fill is meant to mitigate against any future subsidance of the soils over the out of service pipe. We can locate the ends of the pipe and middle, and there are no service branches. I am looking for tips on technique (such as high point venting), recommendations on the composition of the grout/slurry mix, etc.





RE: AC Pipe Abandonment in place
RE: AC Pipe Abandonment in place
RE: AC Pipe Abandonment in place
RE: AC Pipe Abandonment in place
sc
RE: AC Pipe Abandonment in place
You will need high end venting. Before grouting try blowing out with compressed air to try to rmove water lying in the pipe. Any remaining water will be flushed out as you pump grout in. Check the flowability of the grout as it exits the vent, ideally the flowability of the grout will be the same as it exits as when it enters the pipe.
Why not phone up your local concrete supplier and check they have a concrete pump, this should provide enough pressure for your purposes. Grout is often used to lubricate pumps and lines before pumping through structural concrete. It is quite possible that the same grade of grout will suit your purposes.
Zambo
RE: AC Pipe Abandonment in place
I have abandoned miles of AC, rotting ductile and cast iron pipes over my career and have never had the need to fill with a grouting (or similar) material. Just my two cents worth, keeping in mind that I do not know all the circimstances surrounding the project.
KRS Services
www.krs-services.com
RE: AC Pipe Abandonment in place
RE: AC Pipe Abandonment in place
Fly ash from your local power station should only cost you a trucking fee as it is a waste product. I have pumped up to 75% solids by wieght 11km.
You could use a mobile concrete pump, Schwing, Putzmeister or other to do it. Fly ash could be slurried in cement trucks and loaded into a portable conrcrete pump. Slurry could then be pumped until your line is full. If you are concerned about voids put a poly pig in front of your slurry to drive out the air with the liquid column.
Sharing knowledge is a way to immortality