Numerical simulation of pile-driving induced-noise propagation into the ocean: effects of sedimentary basins and interaction of two distant pile driving operations
Résumé
Pile driving is a major source of the noise generated by human activities in the ocean. The complex wavefield which is generated by this activity depends not only on the water column characteristics but also on the structure of the sediment layers beneath. In general, this structure is considered horizontally stratified with a gradient of mechanical properties. In this presentation, we propose to investigate a sediment configuration with a heterogeneous structure including two sedimentary basins. For this purpose, we performed several numerical simulations using a 2D time-domain spectral element method which allows for accurate handling of the characteristics of the complex marine environment (complex bathymetry and elastic sediments). We emphasize the presence of interface waves of the Stoneley-Scholte type. Additionally, we propose a method to generate 3D interaction maps of two distant pile driving operations using only one 2D simulation. Our results show the importance of taking into account the phase of the signals to correctly evaluate the interferences between the two operations.
Domaines
Acoustique [physics.class-ph]
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Licence : CC BY NC ND - Paternité - Pas d'utilisation commerciale - Pas de modification
Licence : CC BY NC ND - Paternité - Pas d'utilisation commerciale - Pas de modification