Contact US

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.

Students Click Here

Bottom Heave of Cut in Clay

Bottom Heave of Cut in Clay

Bottom Heave of Cut in Clay

I am designing a 20 ft deep trench with 10 ft of granular fill on top of 10 ft of clay. Using the factor of safety equation for bottom heave in Das Section 10.5, the cohesion c is multiplied by H and divided by B'. My question is, should I multiply c by 20 ft (where H is the full depth of the cut) or multiply c by 10 ft (where H is the depth of the clay). My thought is that the benefit of the cohesion only applies to the height of the clay and not the height of the fill. Cohesion is not depended on the depth of embedment. So I should use cohesion times 10 ft.
Here are the equations and diagram from Das followed by calculation. Thank you!

RE: Bottom Heave of Cut in Clay

By 20 feet.

Mike Lambert

RE: Bottom Heave of Cut in Clay

Is there a similar formula for a 'pit' as opposed to a trench?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?


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


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. 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