High E.I.

[lsmfse]

Could someone explain to me what kind of soil that has an E.I. of 230 is?

 

[civilperson]

If you are referring to "Erodibility Index", then that value sounds a bit extreme. Zero to 8, is suitable for row crops; 8-24 needs cover and terracing. The highest value I have seen is in the 80's, sugar clay in Oklahoma.

 

[lsmfse]

No, I'm referring to the "Expansion Index".
Thanks

 

[genomty]

It is the kind of soil you don´t like to encountere behind your foudation.

I dont really know if it is possible that a soil can reach that EI but ASTM d 4829 indicate that soil heaving and EI higher than 130 has a very high potential to swell.

Probably you are dealing with a clay having a high content of kaolinite minerals, son, a special foundation design is requiered see USACE Foundation is Expansive soils, mat desing by the Building Research Advisory Board, or PTI postensined Institute, where is you project located?

 

[muuddfun]

An EI of 230 is very very high, the highest I have seen is about 200. Take a very careful look at what you want to do with this stuff. That much expansion can put a lot of pressure on a foundation.

 

[lsmfse]

Thanks for all your answers. In our area, EI's of 150 are common. I didn't realize you could get such a high EI! We are planning on using at least 4' of non-expansive import below bottom of post-tension foundation.

 

[bob3306]

For a second I though this post was about something else.