Using UKOOA Code

Hello-

Can someone confirm how allowable stress and code stress are calculated in Caesar II when the UKOOA code is specified? Thanks.

There is a large section on FRP stress analysis in the Technical Reference Manual. The equations used for UKOOA can be found in the Quick Reference Guide.

Thank you.

I was hoping for an explanation as to how the variables in the equations are determined from the inputs. Specifically Caesar II uses SH (I think) and f2. Somehow, from that info, it calculates LTHS, sigmaa(0:1) and sigmaa(2:1) in order to calculate the "code stress". How does it do that?

You might enjoy reading two Newsletter articles that review these data. See December 1997 at: http://www.coade.com/newsletters/dec97.pdf and June 1998 at: http://www.coade.com/newsletters/jun98.pdf

Go to \caesarii\c2_docu and open "c2tr.pdf". ("caesarii" is your installation directory.) Once the PDF is open, navigate to page 6-85 and 6-86.

You also need to reference one of the FRP data files located in \caesarii\system - I suggest "wavin73.frp". Open this with a text editor, such as NotePad. The 'sigma' values defining the interaction curve are located at the bottom of the file.

Thanks - I'm reading.

With respect to the FRP data files, when you don't have a specific vendor or are using custom pipe, how is the data file generated - or which is used?

The data file isn't generated. This information needs to be obtained - it is considered "input".

FRP analysis is tough in this regard, because even the same pipe (designation) from the same vendor, but from two different batches (say with a 5 deg change in ambient temperature) could have different properties. Unfortunately, this isn't the same as saying "A106-B".

I agree- that's why I'm nervous. I understand that SH on the input form is f1*LTHS. The ratio of the sigmas is the R. What happens when the R is left blank? It can't be zero as its in the denominator. Also the the program print the envelope? That would be really handy for key points in the system. Thanks.

Hi

I would suggest looking into ISO 14692 Part 3 and AWWA M 45 for a good basic treatment of the FRP piping.

Remember the allowable stresses in FRP should be checked in the stress envelope supplied by the manufacturer. You have to agree upon a supplier before you seriously work on the frp stress analysis.

Vendor sites like Ameron and Sarplast are a good source for FRP design guidelines

Rick,

If you leave "R" blank, it defaults to 1.0, which is like assuming the envelope starts with a horizontal line.

Unfortunately no, the program won't print the envelope.