Open caisson structure with friction reducing, sinking material assisting and leakage preventing functions

The invention discloses an open caisson structure with friction-reducing and sinking-assisting material leakage-proof functions, an open caisson is provided with a cylindrical well wall, the bottom of the well wall is provided with an annular blade foot, an annular cavity is defined between the well wall and surrounding soil, and friction-reducing and sinking-assisting materials are injected into the annular cavity during open caisson construction so as to reduce friction force between the open caisson and the surrounding soil. The outer surface of the bottom end of the well wall shrinks in the radial direction to form the blade foot, the radial inner end diameter of the blade foot is the same as the inner diameter of the well wall, the outer diameter of the blade foot is linearly reduced from top to bottom, so that surrounding soil protrudes in the radial direction at the blade foot to form a big-end-up horn mouth, and the blade foot is pressed on the horn mouth. The method is used in open caisson constructi