Consolidation Parameters from CU Test

[DanielP]

I have small diameter (1.9 inch) undisturbed samples of clay that are two small for consolidometer machine. How can I get consolidation parameters from CU triaxial test or CD test?

 

[Focht3]

Hmmm,

You really can't - the word 'disturbed' says it all. You need undisturbed samples for performing consol tests.

You can use the water outflow measurements with time to calculate the soils' consolidation properties. But you need good samples first -



Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora. See faq158-922 for recommendations regarding the question, "How Do You Evaluate Fill Settlement Beneath Structures?"

 

[ashjun]

Hi,
I think Daniel refers to "undisturbed" samples. There are standard formulae you can use when you run either of the two triaxial tests. Look up in any soil mechanics textbook.
Regards

 

[Focht3]

Oops! Age gets me again! {Where'd I put those darn reading glasses, anyway?!}

Sorry, [blue]DanielP[/b].

You will have to get a special oedometer set-up. It's set up for a 1.95 inch diameter sample. (Measure yours to see their actual diameter.) I know they exist; I purchased one about 5 or 6 years ago. (Just one. Don't use it often...)



Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora. See faq158-922 for recommendations regarding the question, "How Do You Evaluate Fill Settlement Beneath Structures?"

 

[BigH]

Do your triaxial tests correctly and you can get the consolidation data and for 3-D effects too rather than just the 1-D effect in a consolidometer. Prof Poulos and Davis and I think a "Lee" in California have looked at relationships of 1-D and 3-D scenarios - don't have the references at my fingertips - sorry.

 

[Focht3]

I think you are talking about Ken Lee at UCLA - died in a cross-country skiing accident about 15 or 20 years ago. (He got lost and died of exposure.) He was active in this area; but I don't have a citation for you.



Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora. See faq158-922 for recommendations regarding the question, "How Do You Evaluate Fill Settlement Beneath Structures?"

 

[BigH]

Probably. He contributed to a book called New Horizons in Geotechnical engineering - or something like that.