Simple question, of what?

Like Atterberg limits work for Clays, limiting porosities do for sandy soils. Therefore especially for sands to be more specific.

Can you maybe provide an example?

I think I might understand the concept here.  You're talking about loose packing v. tight packing:

-   -   -   -   -   -
  -   -   -   -   -
-   -   -   -   -   -

compared to:

- - - - - - - - - - -
- - - - - - - - - - -
- - - - - - - - - - -

I believe I learned about this in my groundwater course in college.  There were lab tests we performed that had to do with movement of water through sand.  I wouldn't be able to give you any specific references offhand, but I'll see if I have anything in my library.  I would search something to do with Darcy's law.  If there is no current data, I imagine it wouldn't be that difficult to come up with experimental data of your own.  

Cheers.  

I think that all you need to do (in the case of a sand) is to run minimum and maximum density tests.  From those tests, you can also get the corresponding limit void ratios and porosities if you know the specific gravity of solids.  These tests are presented in the ASTM manual, and many other methods are also available.  A great resource is the ASTM STP 523 "Relative Density Involving Cohesionless Soils."  This publication is a collection of papers that discuss many of the caveats involved in performing limit density (or void ratio, or porosity) tests.  I found it very interesting.

MRM,

That publication sounds generally interesting.  Do you know where one would be able to find a copy?

Hey friends,

why don't you check these references.

ASTM D 4254-91, Annual book of ASTM standards. USA: ASTM VOl:04.08 (1999), p. 518
ASTM D 4253-93, Annual book of ASTM standards. USA: ASTM Vol:04.08 (1999), p. 505

Eris Uygar