Scour caused by propeller jets around harbour structures results in considerable damage. Scour protection for these structures has been of increasing importance in their design. This paper addresses an experimental investigation into the scour on armoured slopes under berth structures. Three different cases were considered for this study, including an armoured layer with an apron, an armoured layer without an apron and an armoured layer with an apron that included a pile on the slope. Propeller jet velocity and scour measurements were conducted in these experiments. Additionally, armoured layer damages on the slope were defined using a damage level parameter. The critical densimetric Froude Number (Fr-d,Fr-cr) was defined for the start of the damage. (c) 2012 Elsevier Ltd. All rights reserved.