Residual strength analysis of internally corroded submarine pipeline based on FOA-GRNN model

In order to explore residual strength of submarine pipelines with internal corrosionꎬ and provide reference for maintenance so as to ensure safe operationꎬ a FOA ̄GRNN calculation method of residual strength was proposed and a prediction model was constructed by using GRNN based on influencing factors like wall thicknessꎬ diameterꎬ corrosion depthꎬ lengthꎬ width and ultimate tensile strength. Thenꎬ FOA was used to optimize the modelꎬ and negative influence of smooth factors were set artificially. Influencing factors and residual strength database were simulated and generated by finite element methodꎬ and trained and predicted through FOA ̄GRNN model. Finallyꎬ with experimental data of pipeline ultimate strength blasting from PETROBRAS Research Institute as an exampleꎬ the prediction model was verified. The results show that average relative error of FOA ̄GRNN model is 16􀆰 53% for residual strength prediction of finite element simulation dataꎬ and 7􀆰 81% for experimental data predictionꎬ 第 6 期 毕傲睿等: 内腐蚀海底管道剩余强度的 FOA ̄GRNN 模型 which are reasonable and accurate.