Experimental measurements of wave-induced scour around a scaled gravity-based Oscillating Water Column Wave Energy Converter

•Scour patterns measured experimentally around a scaled Oscillating Water Column.•Scour shown to undermine the structure, comparable with the tunnel erosion effect.•Undermining scour leads to settlement of the gravity-based structure.•Increasing the corner curvature shown to reduce scour depths by 23%.•Comparison with field observations reveals similar scour patterns.