INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Second Stage Shear Strengths - Rapid Drawdown

Second Stage Shear Strengths - Rapid Drawdown

(OP)
I would like to confirm my assumptions on input values for shear strength values and methods for the second stage condition using UTexas.

Based on the manual for UTexas, it is my understanding that a composite shear stength envelope should be developed based on the effective stress and the R envelopes. The effective stress values are simply the values obtained from the CU test. However to develop the R envelope, the shear at failure for each modified mohr circle is determined based on the normal failure stress difference (deviator stress) divided by 2 and multiplied by the cos of the effective stress angle of friction. After computing and drawing the envelope the R envelope cohesion can be determined along with the angle of friction. Here is were I hit a gray area. To determine the intercept, one must determine the angle between where the envelope intercepts a circle and the corresponding max shear for a given circle. Once I do this and solve for the resultant intercept fiction angle and cohesion, these values are very close to the total stess envelope provided in the CU test results. Therefore, is the total stress envelope and the R envelope the same? Thanks!

RE: Second Stage Shear Strengths - Rapid Drawdown

"Total stress envelope" is, in my opinion, a bit of a misnomer. It would be better to call it an "undrained strength envelope," since it gives undrained strength as a fn. of effective consolidation stress, not of total stress.

If I understand your question properly, the R envelope is the same animal, giving Tau-ff as a fn. of Sigma'c for the CIUC test.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close