Hi there
I want to stress analysis to a pipe line made of GRE material (glass reinforced epoxy).
Is it possible to analyse GRE pipe in CAESAR?
if yes, how to insert material properties? (e.g Wt/sch)
if no, what other software can I use to perform the analysis?

Thanks in advance

There is a large section on GRE (FRP) piping and analysis in the Technical Reference Manual. If you're not using one of the FRP materials that CAESAR II supports directly, you can follow the guidelines (in the Technical Reference Manual) to build your own ".frp" material file. Check the "FRP" tab in the Configuration Module for additional FRP settings/options.

It is not necessary to use a ".frp" file. That is only helpful if you use the same material in multiple files. You can also insert the material properties directly into CAESAR II.
A lot of other information about FRP pipe stress analysis can be found in this forum using the search function.