Saturation of the sample at triaxial test

[Regenbogen515]

Hi,
I am doing CU triaxial test on silty sand sample ( sand + 40% low plastic fine content ), I faced with a problem in saturation phase.
I let the Co2 gas goin through the sample about 1 hour then using deaired water, but after 1 day waiting the water does not
move through the sample any more, also I have used cell pressure 2.5 bar and back pressure 2 bar to remove the rest gas in voids, but the sample would not fully saturate.
Would you please suggest me to find the best solution for this problem?

 

[L0k]

Hi, Regen
How much your B-value? if it is equal or more than 0.95. That should be ok.

 

[Regenbogen515]

Yes, you are right, but in my case its around 0.75-0.8.

 

[fattdad]

you need more backpressure, which means you need more cell pressure too. It seems you are at and effective stress of about 1,000 psf. Does that replicate the in-situ effective stress? Then again, this may be a recompacted sample, which means you likely compacted it near the optimum moisture content, which is likely to be about 85 percent saturation.

I agree wtih L0k, if the B-value is 0.95, you're there. A B-value of 0.95 does not correlate to 95 percent saturation, it's greater.

f-d

ípapß gordo ainÆt no madre flaca!

 

[Regenbogen515]

Thank you very much for your comments.