Research On The Bearing Capacity Of Corroded Submarine Pipelines Under Different Loads

As the most important tool in petroleum transportation industry,submarine pipeline is prone to corrosion defects in the long-term working process due to the complexity of its working environment.The existence of corrosion defects has a great impact on the safety performance and service life of pipelines.Therefore,in order to avoid oil leakage caused by corrosion defects,it is of great significance to evaluate the ultimate bearing capacity of submarine pipelines.Based on the research of scholars at home and abroad,the bearing capacity of corroded pipelines under the axial compression,bending moment,coupling of axial and flexural action and combined action of internal pressure and axial pressure was studied by full-scale test and finite element analysis.The main contents of the work are as follows:(1)The bearing capacity and failure mode of rectangular corroded pipelines with equal depth under axial load,bending moment load and coupling of axial and flexural action are studied by designing three sets of full-scale static test tests of submarine pipelines.(2)The static model under three kinds of loads is established by ABAQUS finite element simulation software,and the results are compared with the experimental results to verify the correctness and accuracy of the model.Then the models with different corrosion parameters are established to study the effects of corrosion depth and width on the bearing capacity and failure mode of pipelines.(3)Based on the results of the finite element model,the formulas for calculating the bearing capacity of pipelines with corrosion defects under axial load,bending moment load and compression-bending load are obtained by fitting method,and the accuracy of the formulas is verified.(4)Referring to the test results in reference[46],bearing capacity and failure modes of pipelines with corrosion defects under combined internal pressure and axial pressure are studied by establishing finite element models.On this basis,corrosion parameters are analyzed.