A sealed and thermally insulating tank which is integrated in a structure which comprises a carrier wall, said tank comprising a tank wall which is fixed to said carrier wall, the tank wall comprising, on the one hand, a primary element and, on the other hand, a secondary element which is arranged between the carrier wall and the primary element, each of the primary and secondary elements including, on the one hand, a thermal insulation barrier which is constituted by insulation blocks, in the form of rectangular parallelepipeds which are juxtaposed in parallel rows, an insulation block (1, 13) of a thermal insulation barrier comprising a layer of plastics material foam which is clamped between two rigid insulation plates (13 a, 303) which delimit the insulation block, the two rigid plates being substantially parallel with the carrier wall in the zone in the region of which they are located and, on the other hand, a sealing barrier which is arranged on each of the thermal insulation barriers, the thermal insulation barrier of the secondary element being fixedly joined to the carrier wall, the thermal insulation barrier of the primary element being fixedly joined to the secondary element of the tank by fastening means which are connected to the thermal insulation barrier of the secondary element, and allowing the primary insulation blocks of the primary element of the tank wall to be pressed onto the secondary insulation blocks of the secondary element of the tank wall, said fastening means comprising a metal plate characterized in that the metal plate (301, 401, 100b, 501) is fixed in a countersinking of a rigid plate (13 a, 303) of a primary insulation block which covers the secondary sealing barrier (502, 304), the countersinking being at the side of the secondary sealing barrier (502, 304), the metal plate (301, 401, 100b, 501) comprising at least one retention zone, and in that said fastening means comprise: a protruding member (310, 108 b, 408b, 504) which is connected via the base thereof to a secondary insulation block which is located in the region of the metal plate, and a connection element (305, 416, 450, 503) connecting said retention zone of the metal plate (301, 401, 100b, 501) to the protruding member, the connection element (305, 416, 450, 503) comprising a retention zone which is in engagement with a stack of resilient washers which are engaged on the protruding member, a nut being screwed above the stack of resilient washers, the protruding member having a threaded head in order to cooperate with the nut (314, 109 b, 409 b, 505), whose screwing applies to the retention zone of the metal plate, via the connection element, a force in the direction of the carrier wall, and in that four adjacent primary insulation blocks each comprise, in the region of a corner adjacent to the other three primary insulation blocks, a metal plate (301, 401, 100b, 501) which is fixed in a countersinking of a rigid plate (13 a, 303) of the primary insulation block which covers the secondary sealing barrier (502, 304), the countersinking being at the side of the secondary sealing barrier (502, 304), the metal plate (301, 401, 100b, 501) comprising at least one retention zone. a protruding member (310, 108 b, 408b, 504) which is connected via the base thereof to a secondary insulation block which is located in the region of the metal plate, and a connection element (305, 416, 450, 503) connecting said retention zone of the metal plate (301, 401, 100b, 501) to the protruding member, the connection element (305, 416, 450, 503) comprising a retention zone which is in engagement with a stack of resilient washers which are engaged on the protruding member, a nut being screwed above the stack of resilient washers, the protruding member having a threaded head in order to cooperate with the nut (314, 109 b, 409 b, 505), whose screwing applies to the retention zone of the metal plate, via the connection element, a force in the direction of the carrier wall, and in that four adjacent primary insulation blocks each comprise, in the region of a corner adjacent to the other three primary insulation blocks, a metal plate (301, 401, 100b, 501) which is fixed in a countersinking of a rigid plate (13 a, 303) of the primary insulation block which covers the secondary sealing barrier (502, 304), the countersinking being at the side of the secondary sealing barrier (502, 304), the metal plate (301, 401, 100b, 501) comprising at least one retention zone.