A sealed and thermally-insulating fluid storage tank comprising at least one thermally insulating barrier retained on a supporting structure and a sealing membrane supported by said thermally insulating barrier, the thermally insulating barrier comprising a plurality of insulating panels (9, 57, 58) retained on the supporting structure and juxtaposed against at least one first and one second adjacent walls (1, 2) of the supporting structure; the tank further comprising an angle arrangement placed at the intersection between the first and the second walls (1, 2) and comprising: - a first and a second insulating blocks (30, 31) respectively retained on the first and second walls (1, 2) of the supporting structure and forming a corner of the thermally insulating barrier; each of the first and second insulating blocks (30, 31) comprising an outer face placed facing the supporting structure and an inner face comprising metal plates spaced apart from one another along the intersection between the first and the second walls (1, 2); said first and second insulating blocks (30, 31) comprising a layer of polymer foam; and - a metal angle structure (49, 50, 51) forming a corner of the sealing membrane and comprising a first and a second wings which are respectively welded onto the plurality of metal plates of the first and second insulating blocks (30, 31); each of the first and second insulating blocks (30, 31) being associated with an adjacent panel of the plurality of insulating panels (9, 57, 58) via a bridging element; said bridging element being fixed straddling an edge, parallel to the intersection, of the inner face of said first or second insulating block (30, 31) and an inner face of the adjacent panel, so as to oppose a mutual separation of said first or second insulating block (30, 31) and of said adjacent panel, the sealed and thermally-insulating fluid storage tank being characterized in that: said bridging element is placed between the sealing membrane and the supporting structure and in that each of the first and second insulating blocks (30, 31) having at least one first and one second stress-relief slots (45, 48) formed in the inner face of said first or second insulating block (30, 31) in the thickness of the layer of polymer foam; the first stress-relief slot extending parallel to the intersection, said first stress-relief slot being situated so as to pass between the edge of the inner face of the insulating block (30, 31) receiving the bridging element and the plurality of metal plates of said insulating block (30, 31); the second stress-relief slot extending at right angles to the intersection, said second stress-relief slot being situated so as to pass between two of the metal plates of said insulating block (30, 31). - a first and a second insulating blocks (30, 31) respectively retained on the first and second walls (1, 2) of the supporting structure and forming a corner of the thermally insulating barrier; each of the first and second insulating blocks (30, 31) comprising an outer face placed facing the supporting structure and an inner face comprising metal plates spaced apart from one another along the intersection between the first and the second walls (1, 2); said first and second insulating blocks (30, 31) comprising a layer of polymer foam; and - a metal angle structure (49, 50, 51) forming a corner of the sealing membrane and comprising a first and a second wings which are respectively welded onto the plurality of metal plates of the first and second insulating blocks (30, 31); said bridging element is placed between the sealing membrane and the supporting structure and in that each of the first and second insulating blocks (30, 31) having at least one first and one second stress-relief slots (45, 48) formed in the inner face of said first or second insulating block (30, 31) in the thickness of the layer of polymer foam; the first stress-relief slot extending parallel to the intersection, said first stress-relief slot being situated so as to pass between the edge of the inner face of the insulating block (30, 31) receiving the bridging element and the plurality of metal plates of said insulating block (30, 31); the second stress-relief slot extending at right angles to the intersection, said second stress-relief slot being situated so as to pass between two of the metal plates of said insulating block (30, 31).