C-U Triaxial Soil Test, Part 4--Shear Testing

Part 4 of 4 webcasts on conducting a laboratory consolidated-undrained triaxial test of the strength of soil

[faisalsahmed]

The best part of the videos is your voice ...very precise and clear

[geotechnicallabvideos]

I cannot thank you enough for showing how to setup, run, and perform essential calculations for this test. Plus those tips about accounting for friction from the bearings, as well as the load from the cell pressure... man, this is a life-saver.

A lot of steps and setup - I can see why labs charge so much for this test.

[davidfranklinhannant]

Wish I would have had this 3 years ago. Here I am writing a procedure for my company following basically the same format you made these videos in. Great work!

[teebamohammad]

Good morning thanks for this great lesson and I think that you tired because this test consists of more detailes so that I have a question that can we do test uu triaxial in the libratory only because it is quick

[redfoxvgc]

Thanks for the extensive videos. I'm learning alot. I have a question about the determination of the stiffness parameters. Based on the deviatric stress and the strain the E50 can be determined from a triaxial shear test. What if we would be doing a multi stage triaxial shear test. The testmonster would have 3 different stages where it is being tested. What stage is suited best for the determination of E50?
Another question is about the reference stress. Alot of soil mechanics (in Holland) are based on a reference stress of pref = 100 kPa. Are the triaxial shear tests results based on a pref of 100 kPa, or does a correlation have to be used to determine the reference value of E50?

[DarrylCastelino]

ok I have a question, you say you're saturating the sample but at the same time the sample is consolidated.... could you explain?

[scientificresearch]

Sir as we see this test is CU that means undrained at sharing stage excess pore pressure takes all the stress.... Due to that sample never gets Effective Stress on soil partical is same before and after loading... Sir plz explain I cannot understand... Consider S=100%

[musaddikhossain]

Sir, so far i know in CU test first comes saturation then consolidation then the undrained shear part. You have completed the saturation stage and then started the shear part. Why not consolidation?

[gokulpatel]

Very goes efforts sir, but i dont get it... How can we shear before consolidation. B value is for saturation, after that we consolidate it right??....May be you missed part of consolidation to include in video

[SunitaDevi-svbo]

When we apply deviator stress... Due to addition of rod volume into specimen cell pressure get changed....so sir how we take cell pressure as constant