The ultimate goal in pipeline design is to minimize material costs without jeopardizing theintegrity of the pipeline system. A greater level of understanding of pipeline deformation behaviour andmore sophisticated analysis tools are required when considering extreme loads and large deformation.The Finite Element Method (FEM) has been used to assess the bending moment and strain capacity ofpipeline under typical design condition and parameters. After the analysis was calibrated to physicaldata, this study investigated buckled profiles and ovality with respect to critical bending response of girthwelded pipelines over a range of typical design parameters. These parameters included diameter,thickness, internal pressure, applied axial load and misalignment amplitudes.The results of this study have indicated that the buckled wave form observed in the profile of the pipelinesis primarily affected by diameter, diameter to thickness ratio and pressure with applied compressive axialload and misalignment amplitudes having lesser effects. Ovality has been shown to be influenced bydiameter to thickness ratio and pressure and to a lesser degree by applied axial load and imperfection.However, ovality has been shown to remain constant over the range of diameters studied.End effects were discovered to be a problem when considering pressurized pipes. This has been shownto be a direct result of the length of the pipeline. While the length of the pipeline in this study was set to3.5 diameters to simulate experimental conditions, the buckled wave lengths show a great degree ofinterference between the central buckle and buckles developed at the ends of the pipe. It has beenrecommended that in further study at minimum, the length of the pipeline be increased to 5 to 6diameters.
展开▼
