Abstract:The toe structure is an important part of the sloping breakwater,and natural rocks are usually used.For port construction areas that lack natural rocks,concrete artificial blocks are needed to replace natural rocks as the toe of the sloping breakwater.Taking a certain overseas port breakwater project as an example,this paper studies the stability of the artificial block toe of the sloping breakwater under the conditions of swell and complex bathymetry through the 3D physical model tests,and optimizes the breakwater toe.The characteristics of the wave action on various parts of the breakwater under the conditions of swell and complex bathymetry and the plans to improve the stability of the breakwater toe are analyzed and studied.The research results show that the wave-breaking water flows generated by waves under swell and complex bathymetry conditions have a strong effect on the inner side of the circular arc section of the breakwater roundhead and the breakwater root,and the 8 m3?Antifer of the original toe plan is unstable under design wave action.The stability of the artificial block toe of the breakwater root can be improved by opening a groove on the reef plate and placing the artificial blocks of the toe in the groove of the reef plate.The Antifer size of the breakwater trunk and roundhead is increased to 12 m3,however,due to the lack of interlocking between the Antifers and their weak resistance to the breaking wave impact,the Antifer at the breakwater trunk and the leeward side (135°-180°) of the breakwater roundhead toe are still unstable under design wave action.For the optimization schemes,the breakwater trunk and roundhead toes use artificial blocks with interlocking properties,and the rocks applied in underlayer of the artificial blocks can enhance the stability of the artificial blocks at the toe.The 12 m3?Xbloc at the breakwater trunk toe and the 16 m3?Xbloc at the leeward side (135°-180°) of the breakwater roundhead toe are stable under design wave action.