Estimation of strains in the dent of a pipeline.

摘要

This research focuses on the development of numerical computational methods of strain around the dented region on pipelines based on the depth of dents alone in both the elastic stage and plastic stage. Firstly, the finite element method is used to simulate the shape of indentations due to different external forces. For the possible error caused by the low spatial resolution of real measured data, the least squares method and bicubic spline interpolation are introduced to refine the shape. Then, the energy method is applied to estimate the membrane strain components in the elastic stage and plastic stage individually. Finally, the membrane strain of actually measured dent profiles is calculated using the recommended method. The calculation results are close to those from the ANSYS model. The conclusion is that the energy method is a good choice to evaluate the strength of the indentations of pipelines.