×
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

Jobs

soil lateral pressure in multi-layered condition

soil lateral pressure in multi-layered condition

soil lateral pressure in multi-layered condition

(OP)
Hello,
Assuing overberdon = 80psf, Rankine theory.
1st layer: ϒ1,Ka1, h1 (layer thickness)
2nd layer: ϒ2,Ka2, h2
3rd layer: ϒ3,Ka3, h3

Lateral earth pressure at to of each layer
80 x Ka1 ------------- 1st layer
(80 + ϒ1 x h1) x Ka2 -----2nd layer
(80 + ϒ1 x h1 + ϒ1 x h1) x Ka3 ----- 3rd layer
For each layer, take the upper layers as surcharges in the calculation.
Please tell me if this calculation is right.

Thanks.
Tony

RE: soil lateral pressure in multi-layered condition

(OP)
Hi, anybody can tell me?
Lateral earth pressure at the top of each layer.

Thanks.

RE: soil lateral pressure in multi-layered condition

Looks correct but you also need the pressure at the bottom of each layer. This is covered in most soil mechanics text books. However, you really should check the soils books before asking online if half of your pressure calculatios are correct. I hope you know that you can't just connect the pressures you calculated at the top of each layer in order to form a pressure diagram.

www.PeirceEngineering.com

RE: soil lateral pressure in multi-layered condition

(OP)
Thanks, PEinc.
Example in 'Trench & Shoring Manual' by state of Califonia department of transportation doesn't count ALL the layers' weight. Page 6-19.
It's surprising.

RE: soil lateral pressure in multi-layered condition

Why not look at the old NAVDOC 7.1 Slope Stability analysis for wedge failure - they have an example of how to compute the driving force (the lateral earth force) for the various layers involved - the principal would be the same.

RE: soil lateral pressure in multi-layered condition

effective vertical stress at any depth times the layer's horizontal earth pressure coefficient equals the horizontal stress.

f-d

¡papá gordo ain’t no madre flaca!

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!


Resources