1. Use real mechanical properties. You can find it here:
Properties of Carbon Fiber or here:
2. To figure out the actual load-bearing capacity of a structure use FOS (factor of safety) - see
I had already found the second link you provided, couldn't understand it very well, your first link is a bit simpler, hope to be able to load corect info.
Will try the FOS, and let you know.
After various errors (connection, fixtures, and mesh) I finally made it