Repair of water carrying concrete conduit

[tonyfahres]

A client asked me a question concerning a structural repair of a concrete pipe conduit. The conduit transports settled water to filter beds as part of the treatment process. Ne concrete is being formed one of the walls of the conduit. The question is when can the conduit be filled and put back into service? Strength is not the concern, leakage and water loss is what we want to try to avoid. Are there any applicable guidelines for this? I am trying to find some background so I can say a number less than 28 days as this is something that needs to be in service sooner than later. Much Thanks!

 

[dicksewerrat]

Why not use CIPP. What is the diameter, pressure, length?

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[tonyfahres]

Maybe 'pipe' is not the right word to use for it. It is a rectangular concrete channel. It is roughly 11 feet wide and 5 feet 6 inches tall. The repair is for a 5 foot length on the side wall. The water flowing through the pipe is not pressurized so the only pressure on the wall would be 2 psi or so due to the depth of the water.

 

[JedClampett]

Usually we say the concrete should reach it's design strength before it is put back into service. That does not mean 28 days, even though the concrete strength is defined at 28 days. Typically, by about 7 days it's reached the design value. Hopefully, you made test cylinders and have enough to test them at intervals.

 

[LittleInch]

Why don't you just seal off this section with some marine ply and some bits of 2 x 4 to provide a bit of rigidity and some sealant while the concrete cures?

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[bimr]

If you can not take the section out of service, consider lining the section with stainless steel or plastic.

 

[cvg]

just repair with a high strength, early setting mix which should be able to reach 4,000 psi after just a few days. for instance, a mix we are working with currently reaches 3,500 psi in 3 days and well over 4,000 psi in 7 days. With enough reinforcement, that should be more than adequate for your small loads.