Hello,

I have to analyze a pipeline made of Fibber Reinforced Plastic (FRP). It belongs to a power plant and the rest of metallic pipes have been analyzed as per ASME B31.1.

Which code should I use?.
Where can I find allowable’s for these kind of pipes?

Could somebody give me some recommendations to proceed?

Thank you for your help

Search *.pdf file in caesar directory. In each file search using keyword FRP. It is a good start. For the property of the pipe ask the vendor if they provide different mechanical/physical properties data with what provided in *.frp file in Caesar directory. If they are different you need to create your own *frp file and load it from configure setup. FRP pipe is unique coz it considers hoop and axial direction in stress field.

For FRP pipe, a better code to be use shall be UKOOA. As described by Samsul, the FRP pipe has unique characteristic with different manufacturer.

Please obtain the mechanical properties from FRP vendor, such as:
- elastic modelus/axial
- Ea/Eh*Vh/a (Poisson Ratio)
- SH1 (UKOOA defined allowable stress)
- R1
- f2 (0.67 for sustained, 0.83 for operating, 0.89 for occasional)
- k (0.85 for liquid or 0.8 gas)
also don't forget the obtain those values in "special execution parameters"
- FRP Coef of Thermal Expansion
- FRP Ratio of Shear Modulus/Emod Axial

Be remind that the allowable for FRP is referring to its unique allowable stress envelop (which built internally by CAESAR II).

A recommended method shall be Anchor the tie-in point between two systems.

Thanks a lot to Alyy and Samsul.

Your help has been very useful.

Now the problem we face is that the code stress at "tee"'s is much higher than the allowable informed by the manufacturer.

The pipe is 2000mm diameter and the bourdon effect is very important, besides the sif thet is 3.9.

The one solution we belive correct is to fill with cocrete the ditch in the area where the Tee is, anchoring it this way.

Does somebody now how to model a soil with infinite stiffness?.

Regards and thanks.

Alfonso M.
Mechanical Engineer

Dear Alfono,

Hope this will help. Go to google, use such combination of these keywords: FRP, thrust block, geo textile, backfilling, manhole, practical installation, ect...