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

qb value- unit point bearing

qb value- unit point bearing

qb value- unit point bearing

Does anyone know how to calculate qb (unit pile base resistance of CPT results) value?
qb = unit point bearing,which is then used to calculate the qc values)
This qb value is used in Belgium practice. It should be calculated by "De Beer"method.
I have searched a lot but i could not get any formulas for calculating the qb value.
I could only find the calculated values, where the formula or calculation is not explained.
The link provided above is the only explanation i could get.
Does anyone know how to calculate these values?

RE: qb value- unit point bearing

Thank you for your reply.
But I am looking for a formula to calculate qb which is unit point bearing by "De Beer" method.
And i need to calculate this qb value by the above method for each soil layer with the provided qc values from a cpt.

RE: qb value- unit point bearing

I don't have any reference specific to the 'De Beer' Method, but in the Canadian foundation Engineering Manual there is a relation for calculating unit base resistance (qt), where qt = kc*qca, where kc is a bearing capacity factor based on soil and pile type and qca is equivalent cone penetration resistance at the pile base (Something to do with averaging qc within a 3/2*pile diameter I believe of the toe - not sure exactly since I've never had to do a calc for these by hand). kc ranges from 0.2-0.55. Section

The same tables can also be found in PK Robertson's CPT Guide 6th edition (http://www.greggdrilling.com/wp-content/uploads/20...).

Unfortunately neither are the De Beer's method so I can't help you there

RE: qb value- unit point bearing

Thank you for your help.

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


White Paper - Implementing a Multi-Domain System
IoT systems are multi-domain designs that often require AMS, Digital, RF, photonics and MEMS elements within the system. Tanner EDA provides an integrated, top-down design flow for IoT design that supports all these design domains. Learn more about key solutions that the Tanner design flow offers for successful IoT system design and verification. 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