Unless you can find a good set of design tables, which I have seen for some other types of pipe, you will need to calculate it. In addition to the traffic loading, the design depends on the pipe diameter, the weight of soil, the trench width, type of and amount of compaction for pipe bedding and backfill, and a few other things.
If you want to learn how to calculate it, you can look here: https://community.ptc.com/t5/Mathcad/Lusk-Flexible-Pipe-Design-zip/m-p/449427
In 2014, I posted two related Mathcad 3.0 worksheets to the PTC Mathcad forums for flexible pipe design. The .zip file includes .pdf printouts of each one for those who don't use Mathcad. These worksheets are heavily annotated and include references.
