Abstract: The invention relates to a device for sealing a caisson comprising a bottom, two upright side walls and a back wall, and intended for carrying out works to a sheet pile wall below the water line, characterized in that it comprises the combination of an inflatable continuous air chamber (8); a series of deformable sealing elements (9); a core (10) which can be displaced between each of said sealing elements (9) and the air chamber (8) and guiding plates (11) and means for allowing the lateral displacement of said sealing elements with respect to the caisson.

Abstract: This invention concerns equipment designed for carrying out work under dry conditions on an underwater structure in particular on a sheet pile planking wall with grooves at more or less regular intervals comprising a caisson brought through two vertical walls and a floor in contact with a sheet pile planking wall and means to keep the caisson pressed against the sheet pile planking wall comprising the floor of the caisson being fitted with horizontally adjustable sealing sheets that slide in the grooves of the sheet pile planking wall.