The ripped-rock embankment is extensively used in construction of Caofeidian because of its simple construction,rapid construction,good adaptability,mature construction method,and high safety performance.However,gap is formed inevitably in the ripped-rock embankment construction,especially in the sea,all around without cover,and gap closure construction affected by the marine natural conditions has always been a difficulty.During construction of Huaneng Caofeidian coal terminal project,we simulate the possible current change process by mathematical model to provide reference for the choice of gap closure time and the setting of construction plan and thus ensure the stability of gap closure riprap in the process of construction.