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

Micropiles to stabilize slope - FHWA method

Micropiles to stabilize slope - FHWA method

Micropiles to stabilize slope - FHWA method

Hi, I am working on a micropile design to stabilize an active landslide, for which we are required to use the procedures in the 2005 FHWA manual for micropile design (NHI-05-039). The procedure gets pretty convoluted when it reaches the step of determining the shear capacity of a single vertical micropile.

The procedure directs you to break the micropile in two at the slip surface (location is known), flip the top portion upside-down such that the 'pile head' is the slip surface, and run p-y analyses (e.g. with LPILE) on the the two portions separately. The shear capacity is determined by applying shear force and bending moment boundary conditions at the slip surface, such that both analyses result in (1) equal slopes at the pile head (i.e. slip surface) and (2) maximum moment equal to the bending moment capacity of the micropile, determined in a previous step.

Per the procedure, the bending moment BC is adjusted until the slopes are equal, then the shear force BC is adjusted until the max moment = moment capacity. But of course, adjusting the shear force BC also affects the slopes, so the iterative procedure becomes a bit of a tail-chaser.

Or at least that is what I am seeing. Is anyone familiar enough with the FHWA micropile procedure to offer some guidance on this tortured p-y analysis?

RE: Micropiles to stabilize slope - FHWA method

Never used that method and splitting the pile is not recommended by Ensoft. I suggest you look at the LPile manual for other options to perform this analysis.

Mike Lambert

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