Abstract: A tank for transporting and/or storing a liquefied gas includes: a plurality of walls, each including, in a direction of the thickness of the wall, a thermally insulating barrier and a leak-tight membrane that rests against the thermally insulating barrier and is intended to be in contact with the liquefied gas inside the tank, the thermally insulating barrier including a plurality of self-supporting heat-insulating panels which each includes a block of polymer foam and a plate, a bottom wall of the plurality of walls includes a first portion at least partially surrounding a second portion of the bottom wall, the second portion including drain. The blocks of polymer foam of the second portion have a density greater than a density of the polymer foam blocks of the first portion.

Abstract: A sealed and thermally insulating tank for transporting and/or storing liquefied natural gas includes a load-bearing structure and a storage structure surrounded by the load-bearing structure. The storage structure includes a first portion and a second portion that are sealed with respect to one another, the first portion and the second portion extending in one and the same plane which is parallel to the load-bearing structure. The tank includes a closure device arranged in the thickness of the storage structure. The closure device includes a first closure member and a second closure member that cooperate with one another to separate the first portion from second portion. One of the closure members includes a first part and a second part that extend in intersecting planes. One of the parts is connected to one of the portions by a fastening device that is arranged in the thickness of the storage structure.