Mechanical properties study of fiberglass reinforced flexible pipeline in marine applications

A mechanical properties study of fibereglass reinforced flexible pipe (FGRFP) in marine applications is proposed based on the reinforced layer interface structure design, the anisotropic layer section mechanical performance test, and the structural strength analysis under the laying operation condition. Based on laboratory tests and referencing ASTM and DNV regulations, the technical design indexes of flexible marine pipe that meet strength requirements have been provided. Through tests, the maximum yield tension of FGRFP is 89.8kN, the ultimate curvature is 3.3 rad/m, the bending moment is 2312.2Nm, the torsion angle is 0.32 rad, and the torque is 2610.4Nm. Based on numerical simulation, static analysis can identify weak points in flexible pipelines. Especially, the feasibility of FGRFP structural section design was verified through dynamic analysis under the combined action of waves and currents. Finally, parameter sensitivity studies were conducted, including the effects of wave/flow direction, wave height, and period.