An Investigation of the Effect of Utilizing Solidified Soil as Scour Protection for Offshore Wind Turbine Foundations via a Simplified Scour Resistance Test

Offshore wind power is rapidly developing as a source of clean energy. However, as local scour of the foundation of an offshore wind turbine can create serious safety risks to the normal operation of the turbine, it is necessary to protect the foundation from scour. In this paper, a new scour protection countermeasure using solidified soil has been investigated via an updated apparatus for a simplified scour resistance test (SSRT). Two types of tests were carried out: an unconfined compressive test to determine geotechnical parameters and an SSRT test to reflect the scour resistance of the soil samples. The results show that unconfined strength is approximately related to the critical flow velocity of the scour resistance as a power function. Soil samples having an unconfined compressive strength of 300 kPa can resist erosion under flow conditions above 3.14 m/s after solidification. In addition, the solidification state of the solidified soil has a great impact on the scour resistance of the soil sample, and the critical scour velocity of the final solidified soil is increased by 80–150% as compared to an initial solidified soil having the same final unconfined strength. These results suggest that attention should be paid to the state of the solidified soil during the construction process. The engineers should control the ratio of cement, water, and soil of the solidified soil according to the hydraulic parameters at the time of construction so that no great loss of solidified soil will occur during the construction process.