how to determine concrete block foundation cracks if can be epoxied or need to demo 2

[delagina]

I have a pump foundation (just a rectangular block) due to old age has many cracks and damaged surfaces and corners.
How do I determine if this is crack is still fixable by injecting epoxy or need to be replaced. Also what epoxy can I use so pump will not have down time.

 

[delagina]

or any good reference/book about this..

 

[WARose]

I don't know about no down time at all......but this sounds like a job for 5 Star. They make a lot of epoxy grouts that are "high early" in terms of strength.

You may want to ask them about the no shutdown situation and get them to recommend a product.

Their web site:

https://www.fivestarproducts.com/

 

[RickyTickyTavi]

ACI 224: Control of cracks in concrete structures. Also, I would hammer sound the foundation, make sure your reinforcement is still engaged with the concrete. Finally the epoxy manufacturer's guidelines generally have information on what kind of cracks you can inject. I agree with WARose on fivestar. Sika and Hilti also have some crack injection products.

Also, just want to add. From personal experience, a lot of those older foundations in contact with the ground and moisture may have ASR (alkali-silica reactivity) of their aggregates. Depending on how advanced it is, your cracks may reform in just a few years.

 

[oldestguy]

I'd not expect-any significant improvement by even the best of crack bonding methods. The question is why? Block walls cant do much in the way of handing differential settlement or loads.

 

[delagina]

OG, this is not a block wall. This is a rectangular "block" foundation for pump. When I said block, I meant no pedestal just rectangular in size and very thick.

 

[charliealphabravo]

1. You might consider whether large cracks through the mass could have been caused by vibration or impact of the operating equipment. In that case the size or reinforcement of the foundation may be inadequate and repair would likely be ineffective.

2. If cracks through the mass are a result of seasonal earth movement then repair may again be ineffective.

3. If it is just damaged corners and surfaces that that should be repairable with proper surface preparation and the use of a low shrinkage concrete repair (whatever is recommended by Sika or others).

4. If none of the above then the limitations on depth and width of repair is a function of the manufacturer's product specifications (for epoxy/acrylic/polymer modified/etc) and perhaps whether access to both side of the crack is practical.

 

[oldestguy]

Sorry, block tends to mean something different than a slab on grade. Even then bonding of cracks is questionable.