R-Value test result

[dan00]

Is it possible to get the R-Value at 300 psi exudation pressure to be 0? In other words, can the vertical pressure applied to the specimen (when placed in stabilometer)be equal to the horizontal pressure? Thanks.

 

[TDAA]

Wouldn't that be a no-strength material?

 

[emmgjld]

The mechanics of the test method will allow a Stabilometer Value down to and including Zero(0). This is usually a nasty clay, not always very expansive. I have had some tests with a slight negative number and usually attributed these to minor problems of running the test (obtaining the displacement) and minor calibration problems.

It is appropriate to check the calibration of the Stabilometer and to observe if the tech is performing the displacement turns in a consistent manner. I am assuming the adjustment for the small amount of air in the oil chamber is properly accomplished. Also, The flexible (neoprene) plug is run prior to each test series to confirm believable answers.