Simulation analysis for repairing defective pipelines with AFRP

As a kind of innovative multi-dimensional reinforced materials, aramid fiber reinforced polymer (AFRP) is often used to repair defective pipelines through winding in multiple layers. The ABAQUS software was adopted to simulate the defective pipeline before and after repairing with AFRP. In addition, impacts of repair thickness, internal pressure and defect depth on repair results were analyzed. The results indicate the following conclusions. First, the pressure-bearing capacity of pipeline with circular pit defects or curvature surface defects can be restored by AFRP. Second, by increasing the thicknesses of AFRP, the circumferential stress of defective pipeline can be reduced effectively. With further increases in AFRP thickness, circumferential stress tends to reduce at a lower rate. Third, when the Mises stress of defective parts in repaired pipeline is lower than the yield strength, the smaller the internal pressure is, the better the repair results will be.