ABSTRACT
This chapter acts as the final part of the topic of “Liquefaction around marine structure”, discussing the fluid-structure-seabed interaction and seabed instability around pile-type foundation with different purpose and regions. As discussed in previous chapters, the importance of marine soil dynamics under wave and current has become more and more significant with the development of offshore oil and gas industry. Its importance is becoming more prominent with the construction of infrastructures for marine renewable energy and submarine energy, such as offshore wind farms. These infrastructures commonly adopt the pile-type foundation like single pile, group piles and jacket support structure etc. In this chapter, these types of piled foundation for offshore wind turbine foundation and possible potential methodology for the protection of these structures are presented. The hydrodynamics near group piles are investigated and found that the near-trapping phenomenon inside the pile group is significantly related to the wave-pile group interaction angle and the oblique ocean currents. Numerical results also reveal that replacing the existing soil layer around piles with higher permeable soil can effectively suppress the soil liquefaction in the nearby region.
