Dynamic soil response around two-layered detached breakwaters: Three-dimensional OpenFOAM model

For the design of breakwaters, the evaluation of wave-induced seabed response around breakwaters is particularly crucial. Most of the previous studies of the wave-seabed interactions in the vicinity of a breakwater have been limited to two dimensions, which cannot replicate the inherent complexity of the ocean environment. Unlike the previous studies, an integrated three-dimensional numerical model is developed in OpenFOAM. In this study, the engineering problem of two-layered detached breakwaters is investigated and compared with conventional one-layered breakwaters in terms of transmission rate, consolidation process, wave-induced seabed dynamic response, shear failure, and momentary liquefaction. Numerical results indicate that the two layered breakwater has a greater ability for wave dissipation regarding to the lower transmission rate found at the shore-ward of breakwaters. The consolidation process reveals that the self-weight of the breakwater has a substantial impact on the stress fields in the vicinity of breakwaters, which will directly affect shear failure and transient liquefaction in the seabed. Ignoring the consolidation process will miss-estimate the failure potential of the seabed, which may result in permanent damage to offshore structures.

Automated summary

For the design of breakwaters, the evaluation of wave-induced seabed response is crucial. Previous studies were limited to two dimensions, while this study developed a three-dimensional numerical model. The study compared two-layered detached breakwaters with conventional one-layered breakwaters and found that the two-layered breakwater had a greater wave dissipation ability due to a lower transmission rate. The consolidation process was also found to have a significant impact on seabed failure potential, emphasizing the importance of considering it in the design process.