×
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!
  • Students Click Here

*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.

Students Click Here

CD vs CU(bar) Triaxial Testing

CD vs CU(bar) Triaxial Testing

CD vs CU(bar) Triaxial Testing

(OP)
A soils testing firm is suggesting that CD testing is not required for a stability analysis of a silty clay compacted embankment soil; rather just CU(bar). Indicating that CD testing is rarely performed. Is there a justification for not performing CD testing for drained conditions on compacted clayey soils (i.e. can CUbar testing be performed instead and would the results be similar)?

My experience says not, but I'm curious how others are addressing)

RE: CD vs CU(bar) Triaxial Testing

Ran properly the consolidated undrained test with pore pressure messurements, CU bar, will give you the same results as a consolidated drained test, CD. The lab needs to be experienced running these tests since they can be tricky.

The advantage to you and the lab is that a CUbar test can be ran in a couple of week or less whereas a CD test on clay could take months to run. This equates to quicker test results at a much lower cost.

It has been years since I've seen a CD test performed.

Mike Lambert

RE: CD vs CU(bar) Triaxial Testing

Consolidated Undrained (CU) and consolidated drained (CD) tests only refer to the fashion in which the testing is conducted. The two will both provide you with effective strength parameters. As GeoPaveTraffic mentions, the CU is quicker to perform. The CU test also has the advantage that it provides you with a useful stress path.
I only recommend CD testing to clients when they request triaxial testing on a dense sand (to exactly establish where failure occurred) or in special circumstances where the Poissons ratio of the soil is specifically sought after.
Approximately 95% of all triaxial testing we conduct is CU testing.

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! Already a Member? Login


Resources

eBook - Integrating the Engineering Ecosystem
Aras Innovator provides multiple options for integrating data between systems, depending on the scenario. Utilizing the right approach to meet specific business requirements is vital. These needs range from authoring tools, federating data from various and dissimilar databases, and triggering processes and workflows. Download Now
Research Report - Simulation-Driven Design for SOLIDWORKS Users
In this engineering.com research report, we discuss the rising role of simulation and the paradigm shift commonly called the democratization of simulation. In particular, we focus on how SOLIDWORKS users can take advantage of simulation-driven design through two analysis tools: SOLIDWORKS Simulation and 3DEXPERIENCE WORKS. Download Now
White Paper - Industry 4.0 and the Future of Engineering Education
With industries becoming more automated, more tech-driven and more complex, engineers need to keep their skills and knowledge up to date in order to stay on top of this wave—and to be prepared for the Industry 4.0 future. The University of Cincinnati offers two online Master of Engineering degree programs designed specifically for practicing engineers. Download Now
eBook - The Design Gridlock Manifesto
In this eBook, you’ll learn 6 ways old CAD technology slows your company down and hear how design teams have put those problems to rest. “The Design Gridlock Manifesto” shares first-hand modern CAD experiences from 15 companies around the world. Download Now

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