Detection of buried foundations

[killswitchengage]

Hi

Are there any non destructive methods to detect shallow foundations inside a house without the use of trial pits ? like geophysical methods for example ?

Thanks

 

[M.IDR]

There are equipments/sensors used to for rebars detection. I hope it would any different types available which will help detect concrete or can use rebars as an alternative for concrete footings.
But still you need to have specific dimensions details of the footing to approve or take any decision.

 

[killswitchengage]

That's the issue. Because there are no clearances outside of the house to perform trial pitswe wanna detect footing dimensions through the tile floor without the need for excavations

 

[studio13]

Long-story short, yes, you can do GPR on the slab to try and identify buried foundations (as well as pipes, barrels, graves, etc...). Now the effectiveness will be based on factors sch as how much reinforcement there is, what are the subgrade soils, moisture content, etc... For example, if there's a lot of rebar on the slab you might get a lot of reflections tha tmight make seeing the foundations clearly. ALso, the signal won't penetrate as deep in wet clay soils. I'd consult a local Geotech firm that also provides geophysics about how effetive they tihnk it would be since they'd be more familiar with local soils (unless oyu have a soils report already).

 

[killswitchengage]

Long-story short, yes, you can do GPR on the slab to try and identify buried foundations (as well as pipes, barrels, graves, etc...). Now the effectiveness will be based on factors sch as how much reinforcement there is, what are the subgrade soils, moisture content, etc... For example, if there's a lot of rebar on the slab you might get a lot of reflections tha tmight make seeing the foundations clearly. ALso, the signal won't penetrate as deep in wet clay soils. I'd consult a local Geotech firm that also provides geophysics about how effetive they tihnk it would be since they'd be more familiar with local soils (unless oyu have a soils report already).

In actuality , we wanna verify that the foundations of a an existing construction meet the ULS and SLS requirements. But we can't do that if we don't have any clue on the foundation dimensions and depth

 

[studio13]

Again, it's possible, but without knowing anything about the soils or the slab you're shooting through, that's the best guess I can give you from my home office. If it does work, you could see where the foundations start and stop as well as how thick they are. I'd assume that would give you an idea of their size that you're looking for.

 

[killswitchengage]

thank you , whats the name of the GPR ? does it have any specific features or frequencies ?

 

[howardoark]

Hi

Are there any non destructive methods to detect shallow foundations inside a house without the use of trial pits ? like geophysical methods for example ?

Thanks

Ground penetrating radar will probably work assuming it's a slab on grade.

 

[geotechguy1]

GPR exists. YMMV though

 

[IRstuff]

They've detected all sorts of stuff with GPR, including buried bodies, so most concrete structures should be detectable. Nevertheless, I would think you'd want to ask around

 

[geotechguy1]

They've detected an awful lot of rocks or other things in the ground that got interpreted as buried bodies and turned out not to be bodies on excavation as well...

 

[EireChch]

I know you cant do a pit inside but can you do one at the edge of the hosue outsidse. Thats what is commonly done, you can get foundation depth, width and thickness very easily