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

Landfill Dewatering SPT

Landfill Dewatering SPT

Landfill Dewatering SPT

I am working on a concrete cap design for a landfill that has crushed tile and a slurry mixture of mostly small pebbles and some small amounts of clay in it. The landfill is about 5 acres in surface area and roughly 20 feet deep. The landfill will be partially closed until the open area (which is filled with water) is filled with the tile and then the slab will be connected to another slab. We did the geotech investigation yesterday and the SPTs were 40-50 in the first 18 inches, water was encountered (roughly level with water in the open space), then the SPTs were 4-6 until 9 feet (when borehole collapsed). I told the client that we need to dewater the open area and after that we should use a compactor before placing the slab as there will be several inches of settlement. He does not see the slab as having any problems with water in it. Is my recommendation reasonable? I will wait on the geotech report but this seems prudent or am I off? Client is hot to trot to lay the slab as they need the room for storage and 18-wheelers will be driving on it.

RE: Landfill Dewatering SPT

Without a significant overloading surcharge first applied for this site, I think you need to compare this to building over muskeg or other very bad support. Very heavy reinforcing is needed and all joints must have full load transfer reinforcing, as I view the job. Expect plenty of settlement of the operating areas.

Your surface compacting will not prevent the deep material from compressing later on. Consider running a rolling surcharge across the site with a pile maybe 10 to 15 feet high. Much better that just hitting the surface.

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