Disclosed is a liquid container adapted to store liquefied natural gas (LNG). The LNG storage container include a sealing wall directly contacting liquid contained in the tank and a structural wall, which is an exterior wall or inner structure integrated with the exterior wall. The container further includes a plurality of connectors mechanically connecting the sealing wall and the structural wall and an intermediate wall structure positioned between the structural wall and the interior wall. The intermediate wall structure is configured to move relative to at least one of the interior wall and the structural wall