Immediate Settlement - Burland Burbridge 1

[Myoho]

Hi, Im writing a spread sheet to calculate immediate settlement using the Burland and Burbridge formula. However Ive come across a problem with the layer thickness correction factor, f1. The equation is as follows:

f1 = H/z1.(2-H/z1)

The problem is that when H/z1 > 2, you get a negative number, which results in a negative settlement i.e. heave.

Can anyone please confirm if this formula is correct or not.

Cheers and best wishes for the New Year.

 

[msquared48]

Are you sure that the portion of the equation is not

(2-H)/z1 ? Then the heave cndition does not exist.

Mike McCann
MMC Engineering

 

[msquared48]

Sorry...don't know what I was thinking here as it still exists for H<2.

Mike McCann
MMC Engineering

 

[msquared48]

I checked on the internet and found the equation - you have it correct. The equation did have a limit of useage mentioned in the previous wording in that H must be less than Z, so for your condition, you cannot use this equation.

Mike McCann
MMC Engineering

 

[Myoho]

Thanks Mike,

Can you give me the link that you used to find the BB equation.

Regards,

Rob.

 

[msquared48]

Unfortunately not, but if you google "Burland and Burbridge immediate settlement", you will get a few links to peruse. The one I saw apparently was a textbook with all sorts of equations and test results.

Mike McCann
MMC Engineering

 

[Mccoy]

Myoho,

if you email me I'm going to send you what you need:

mccoy twothousandandfor twothousandandfor at yahoo dot com

No blanks, years in numbers rather than in letters

 

[STVU]

Myoho;

Have you considered "Peck & Bazaraa" "NAVFAC method" or "D'appolonia" Just curious to know why Burland method?

In ASCE's geotechnical special publication No. 15, D'appolonia method was most accurate between predicted versus observed settlement study.