Grab dredgers encounter various problems during dam removal construction in strong currents（current velocity of 3-4 m/s），such as difficult docking for barges，serious anchor dragging of grab dredgers，excavated rocks stuck in grab cracks，insufficient fullness of grabs，inability to grab overlarge block stones. To solve the above problems，this paper studies the anchor distribution of a grab dredger，the segmentation of the construction area，the grabbing process of the grab dredger，and the crushing of super-large block stones. By taking various measures，such as adding a traveling anchor to the grab dredger，adjusting the construction direction of the grab dredger and the construction segmentation，changing the grabbing direction of the grab，and cleaning the rock with the grab after it is crushed by the rock hammer of the grab dredger，this paper solves the problems of restricted anchoring，restricted barge docking and separation，serious anchor dragging，and difficult excavation during the construction of rock dam removal by a grab dredger. Moreover，the paper expands the adaptability of grab dredgers to project construction and increases the daily output of the grab dredger by more than 40%. It can provide a reference for similar hydraulic reclamation projects.