The words of Bruce Hebb reminded me of one of the results of modeling expansion joints. CAESARII applies an expansion joint pressure thrust as a force at the ends of the expansion joint element -not at the ends of the pipe run (elbow, tee, cap). In reality the pressure thrust at the pipe ends will result in tensile axial stress with an expansion joint, but with CAESARII forces applied at ends of the expansion joint element, the pipe's axial stress would be computed to be compressive when pipe elbows are restrained.
Since the size 30" pipe area and 140 psi produces 100k thrust loads, I would suggest that tie rods be used for thrust restraint ( between elbow pairs ; tie-backs to vessel ), instead of designing structural steel to restrain the high loads. If the size 30" FRP is routed underground, then concrete thrust blocks at the changes in direction could be best restraint.