Three-dimensional finite element modeling for wave-seabed pipeline interaction

The wave-seabed-pipeline interaction problem is particularly important for coastal geotechnical engineers involved in the design of submarine pipelines. However, most previous investigations have been only limited to two-dimensional cases, any directional wave forced on buried pipeline cannot be taken account. We will examine the problem of wave-seabed-pipeline interaction from the aspect of marine geotechnical engineering in three-dimensions. In this study, we will establish a three-dimensional finite element model to investigate the basic mechanism of wave-seabed-pipeline interaction. In the model, the boundary between soil and pipeline will be considered. Unlike previous models, the oblique waves are also considered in the new model. Based on the new three-dimensional finite element model, effects of wave characteristics (including wave direction), soil behavior and properties of the pipeline (such as dimension of pipeline and size of pipeline, etc.) on the wave-induced soil response will be examined. Moreover, the internal stresses of buried pipeline change significantly with different properties of the pipeline, especially for the case of oblique waves. This research validates the accuracy and effectiveness of our mathematical model and simulation program. Hopefully, it is expected to be provided for the underwater engineering practice.