Mooring of wave energy system using dynamically installed anchors

This study investigated the response of a dynamically installed anchor as an integral part of a model scale wave energy system through a field trial performed in the Swan River, Perth, Western Australia. The field trial involved a cylindrical wave buoy, taut-moored by a steel spring and a stiff mooring line to a dynamically installed anchor in a soft soil site. The buoy-spring system was designed to resonate at approximately 1.15 Hz, which is within the high-frequency tail of a spectrum of typical wind generated waves in the Swan River. The dynamically installed anchor was a 37 kg slender cylinder with 60 degree cone tip, with a shaft diameter of 0.089 m and a total length of 0.88 m. In the field trial, the instrumented anchor was first installed by free-falling into the riverbed and found to embed to 2.5 times the anchor length. The anchor was then connected to the model wave buoy-spring system under taut-mooring, and subjected to wave loading before being pulled-out. The anchor was found to produce a pull-out capacity two times the dry anchor weight.