How do I determine soil permeabilty from PSD curves 1

[Myoho]

I have PSD curves for a well graded glacial sands and gravels. I would like to estimate the permeability of the soil. I have tried using grading curves for using the uniformity coeficient and the D10 value. However they only seem suitable for uniform graded soils as does Hazens formula. Does any of you American geotechs know of an answer.

 

[SUGARCANE]

The Kozeny-Carmen Method is described in Soil Laboratory Testing, Vol 2, K H Head (available from ELE International).

It shows a worked example in section 10.5.3.

Although the example shown is a sand, it suggests the range for is 20mm-0.3mm for soils with permeabilities ranging between 1.0 x 10^-1 to 1.0 x 10^-5.

However, if you dont have the samples available you may have to make some assumptions as regards the materials shape, dry density and specific gravity.

Hope this helps.

 

[Myoho]

I have KH Head in the library. THanks for the tip its just what I was after.

Best Regards,

Rob Kitchen

UK, Liverpool.

 

[SUGARCANE]

Let me know how you get on with it.

I have never used it, just remembered seeing it whilst looking for Hazens formula one time.

Good to see another UK user on eng-tips. Its a pitty there isn't a UK equivalent.

 

[Myoho]

I have just written a spreadsheet utilising Kohzeny - Carmen Method and the Hazen Method. Both methods are giving me k values of around 10^-3 m/s. Saying that Im not sure whether to input voids ratio as a percent or a ratio.

BTW Im working on contact for Montgomery Watson in Warrinton. Where are you based, I may even know you.

Cheers,

Rob.