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Existing Foundation Corrosion mitigation / repair

Existing Foundation Corrosion mitigation / repair

Existing Foundation Corrosion mitigation / repair

I'm working in an area where existing foundations were specified to be constructed with Type V Sulfate Resistant Concrete with slag or pozzolan and maximum 0.4 water-cement ratio.
The soil is highly corrosive and contains sulfates.
Unfortunately the specification was ignored. Deterioration of the concrete could begin to occur within five years.
I'm planning to recommend excavation, where possible, and coating the tops and sides with bitumen coating, to the extent the foundation surfaces may be exposed.

My question is regarding surfaces that cannot be exposed and the underside of the foundations:
Is there a system for injecting a protective grout into the soil and adjacent to the foundation surface that may act as a barrier to prevent sulfate attack?
I'm thinking of something where small boreholes may be installed near the foundation and then grout pressure injected around and below the foundation.
I don't know if that's a pipe dream or such system exists. If it does, I'm sure it will depend on the granularity of the soil, as I assume it would be
difficult to inject grout into cohesive soils / clays.

RE: Existing Foundation Corrosion mitigation / repair

Has this plan on "sealing" the concrete accessible zones ever been evaluated as to actual benefit? I liken it to painting a corroded metal object. Once the damaging stuff is there, might the coating even cause more problems than it fixes? As to injecting something to make a barrier, this has worked for some types of treatments (to change the characteristics of the soil) only when the soil is very porous, such as clean sand and the liquid is low on viscosity. Most of those injections are used for compacting the soil, lifting something above, etc., not usually for making a barrier to dissolved liquid flow as by capillarity action.

RE: Existing Foundation Corrosion mitigation / repair

How long have the existing foundations been in place? Is there deterioration, or is it just assumed that it will occur?

RE: Existing Foundation Corrosion mitigation / repair

The foundations have been in place approximately one year. At this time, there is no evidence of deterioration.
It is assumed it will occur, but perhaps more than just an assumption based on the soil characteristics.

RE: Existing Foundation Corrosion mitigation / repair

If deterioration has not occurred, it is only an assumption that it will. The question I have is, will it be more difficult to access and fix at a later time, if deterioration does begin to occur?

There appears to be significant dispute of whether sulfates in soil will actually result in deterioration of concrete in the field, or whether it's a phenomenon that only occurs in the lab tests.Sulfate in the Soil and Concrete Foundations

If monitoring the foundation for deterioration isn't feasible, it seems treatment of the soil with lime may be a mitigation option. Guidelines for Treatment of Sulfate-Rich Soils and Bases in Pavement Structures (TXDOT)

RE: Existing Foundation Corrosion mitigation / repair

Had a similar problem with slabs sitting on salt laden sand and corrosion set in. The "consultant" for the contractor had a design to "seal" the sides of the slab to stop the corrosion. They didn't consider the salt water underneath the slab. Initially our corrosion consultant recommended cathodic protection which probably worked for the early slabs. But not everyone did this and some slabs crack in half - horizontally. We pulled up the rug in one residence and one could see the rust from the reinforcing grid.

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