concrete tank

[mcandace]

I have a leaking finished water tank. The concrete tank is leaking around a piece of timber blocking that the contractor must have lost in the form. We X-ray'd the wall to see if we could detect how deep the block went. It appears to be no more than 1" square. However the 12"+ thick wall is seeping through the area. Assuming that the timber is more subject to cracking the wall during freeze thaw cycle, we want to remove it. This will leave a decent penetration in the wall and is highly likely to stay damp because of cracking.

What is the best option for filling and patching concrete?

 

[TRAK.Structural]

Probably need to install a retrofit waterstop and fill with non-shrink grout. I would require the contractor not cut any of the existing embedded reinforcing when doing the demolition.

 

[ANE91]

Can you post the X-Rays? Nobody’s ever paid for it when I’ve offered; it’s so expensive. I also didn’t think that you could X-Ray wet concrete. Maybe you meant GPR?

So it’s a 1 inch by 1 inch by 12 inch piece of wood? And it provides a perfect channel for water to wick along, out from within the tank? Yikes Mr. Contractor.

In any case, the fix is easy, assuming that you can drain the tank. There’s probably a crack that needs injecting, or at the very least routing and sealing. You also want to patch in new concrete that won’t shrink away from what’s existing, after cutting/drilling out the wood. Dry pack is great for something this small. You could also slap on a latex bonding agent.

Peter Emmons published a fantastic book on concrete repair, if you need a reference.

 

[HTURKAK]

What is the best option for filling and patching concrete

Use XYPEX repair mortar and XYPEX plaster . Alternatively polyurethane pressure injection may be considered .

 

[Enable]

Typically we would use products marketed as a "hydraulic cement" for such things since they are designed to have a slight net expansion. Redi-Plug by King is common in my area. If you're not going to drain the tank and want to go a step further you could consider installing a crystalline waterproofing as an added measure.