Hi Everyone,

I used to input soil properties in accordance with Basic Soil Parameters in Caesar II for the buired pipelines,and now trying to work with the soil properties in accordance with American Lifeline Alliance guidelines.

I came accross with a correction notice in ALA website which is given in the link below:

http://americanlifelinesalliance.com/pdf/11-4-04AdhesionCorrection.pdf

I am not sure about the date of this correction notice, and cannot find it if I enter the website directly. However, I get this without any correction ( there is no change from the guideline dated 2001) from the latest guideline (2005) in the link below.

http://www.americanlifelinesalliance.com/pdf/Update061305.pdf

I always find different result from Caesar II for the axial stiffness for the pipeline when I use the latest version (2005).

I was wondering if someone can confirm that the correction in the previous link is the latest.

Thanks in advance and kind regards,

Ibrahim Demir

I guess I should not look for the confirmation. The Figure B.2 proposed equation curve results gives the confirmation for the requirement of the correction (where c is KPa/50 not KPa/100).

I have checked the Caesar II results with the spreadsheet calculation after this correction, they are the same.

Thanks again and kind regards,

Ibrahim Demir

CAESAR II will take user data and convert to internal units before processing. So CAESASR II will be using ksf in the calculation no matter what units you use.

I type "ksf=" in Mathcad and Mathcad finished this equation: "ksf=47.88kPa". The change makes sense to me.

I wonder to whom I report other issues with the document. I believe a few terms in the Nqh matrix are not properly signed.

The following book is more clearer than ALA document but follows the same mistakes:

http://www.iitk.ac.in/nicee/IITK-GSDMA/EQ28.pdf

I think these documents need more interpretation and corrections since the users are most likely mechanical engineers who do not have any geotechnical background and in oil and gas industry.

Nqh is correct for 30 deg of friction angle only. The rest seems incorrect.

Kind regards,

Ibrahim Demir

Please excuse my mistake, Nqh is NOT CORRECt as David said for any angle. It was somehow on a point that mached the expected number and mislead me.

Regards,

Ibrahim Demir

David,

As you are aware of the problems, I guess, Caesar II follows the correct information/guidelines for the soil modelling in accordance with ALA. Please confirm.

Thanks and Kind regards,

Ibrahim Demir