Pile foundations for offshore wind turbines are subjected to large lateral loads. By mounting wings on the perimeter of regular monopiles, winged monopiles have shown better performance in resisting deformation under horizontal loading. However, hazardous effect local scour bearing capacity installed sandy seabed has not been systematically evaluated. In this study, a modified Mohr–Coulomb mode...

Autonomous underwater vehicles (AUVs) are robotic platforms that are commonly used to map the sea floor, for example for benthic surveys or for naval mine countermeasures (MCM) operations. AUVs create an acoustic image of the survey area, such that objects on the seabed can be identified and, in the case of MCM, mines can be found and disposed of. The common method for creating such seabed maps...

For FY14, the first objective was to investigate the statistics of the mode intensity that result from scattering from a randomly rough seabed surface in a shallow water environment. The specific objective was to examine the feasibility of using a 2-way coupled mode methodology to analyze observed monostatic reverberation collected off Panama City, FL in 2013 in the 2-4 kHz band. The second obj...

For FY14, the first objective was to investigate the statistics of the mode intensity that result from scattering from a randomly rough seabed surface in a shallow water environment. The specific objective was to examine the feasibility of using a 2-way coupled mode methodology to analyze observed monostatic reverberation collected off Panama City, FL in 2013 in the 2-4 kHz band. The second obj...

This paper proposes an original method for the 3-D reconstruction of seabed from multiple sidescan sonar images. The proposed method adopts a stereo-like vision approach based on a combination of the GPS positioning and the image matching technology to correspond among multiple sidescan sonar images taken from different viewmints. and then estract the 3-D structure information of 'seabed from t...

There are different mechanisms of seabed scattering which are due to different types of seabed medium irregularities, which are roughness of the seabed interfaces, and volume heterogeneity: continuous (spatial fluctuations of the sediment acoustic parameters) and discrete scatterers (or sediment inclusions, such as relatively large shells and shell fragments). Given different environmental cond...

Seabed sediments of commercial ports are often characterized by high pollution levels. Differences in number and distribution of bacteria in such areas can be related to distribution of pollutants in the port and to sediment conditions. In this study, the bacterial communities of five sites from Leghorn Harbor seabed were characterized, and the main bacterial groups were identified. T-RFLP was ...

Analysis and interpretation of monitoring data for the seabed bathymetry local to offshore windfarm foundations has shown how the scour develops in time and highlighted variations between sites with different seabed sediment characteristics, i.e. sands and clays. Results from European offshore windfarms have generated a unique dataset for comparison with previously published data. Where surfici...

Recently, a technique has been developed to image seabed layers using the ocean ambient noise field as the sound source. This so called passive fathometer technique exploits the naturally occurring acoustic sounds generated on the sea-surface, primarily from breaking waves. The method is based on the cross-correlation of noise from the ocean surface with its echo from the seabed, which recovers...