Elastic-plastic buckling of pipes with asymmetric dual corrosion defects subject to external pressure

• Published in: Ocean engineering Vol. 240; p. 109975
• Main Authors: Wu, Hang, Zhao, Haisheng, Li, Xin, Feng, Xin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.11.2021
• Subjects: Buckling; Corrosion defect; External pressure; Pipeline; External pressure; Buckling; Corrosion defect; Pipeline
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2021.109975

In the deep-sea environment, pipelines are prone to buckling instability under the coupling effect of hydrostatic pressure and corrosion defects. This instability phenomenon is affected by the pipe dimensions, material parameters and corrosion defects. Based on the shell buckling theory, a semi-analytical method is proposed to analyze the elastoplastic buckling response of the pipe with dual corrosion defects. The buckling pressure of the pipe can be solved by the characteristic equation numerically. Then, the results of semi-analytical approach are in good agreement with those of experimental tests and FE analysis, which verifies the accuracy of the approach. The effects of geometric dimensions, material parameters, corrosion defect depth and angle on the buckling pressure of the pipe are analyzed in details. In addition, based on the FE model, the collapse mode and the post-buckling response of the pipe with asymmetric dual corrosion defects are considered. The application scope of the semi-analytical approach for pipes with different defect lengths and initial ovality is analyzed. Finally, the semi-analytical approach is extended for pipes with multiple corrosion defects. •A buckling pressure equation is developed for the pipe with asymmetric dual defects.•The equation is verified based on experimental tests and finite element analysis.•The effects of various parameters on the buckling pressure are investigated.•The post-buckling responses of the corroded pipe are analyzed.•The application range of the proposed equation is further extended.