×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• 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.

set back formula

set back formula

(OP)
how to calculate the set back from the toe of my up slope that has a stability key 15' x 3' at the toe? Formula? cross section?

RE: set back formula

mhochman,

Jeff

Jeffrey T. Donville, PE
TTL Associates, Inc.
www.ttlassoc.com

RE: set back formula

(OP)
I found out what I needed was to show the zone of influence 45 degree line from the toe of the slope out and show that the pool will not cross that line.
Thanks,
Mark

RE: set back formula

Wrong!

45 degrees is too steep.  The foundations for the pool need to be behind a line drawn from the toe of the slope equal to the long term stable slope plus a factor of safety.

For a slope that is composed of granular soil with say a friction angle of 35 degrees the slope angle should be equal to:

Tan(B)=Tan(35)/1.5

where B is the angle of the line drawn from the toe of the slope.

There are other approaches but the 45 degree line that you imagine is what geotechnical engineers generally assume that the vertical stresses shed at beneath a footing.  It has nothing to do with the stability of the slope.

If you have groundwater discharge or clayey soils then a more detailed analysis is required.

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.

Resources

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
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a partâ€™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:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!