Laboratory experiments on scour around flat circular buckets for high waves and strong current at Wido Windfarm, Westsouth Sea, Korea

Laboratory experiment on scour around three circular suction bucket foundations was carried out at Kookmin University basin, 0.8 m wide, 1 m deep, and 23 m long. The buckets form the foundations of wind power towers of Korea Westsouth Sea Windfarm. Bed material at the site is sand, and finer sand was chosen for laboratory modelling test. The strongest current of 1.03 m/s, the maximum significant wave height of 5.3 m, and the maximum wave height of 8.1 m were undistortedly scaled down by 1/70 in length. Measured scour depths are all under 0.6 times the bucket diameter. Experimental results for currents have been compared with a numerical model STEP, and its modified version STEP-K. Both models over predict the scour depths around the buckets, and also predict earlier evolution of the scour compared to the laboratory measurements.