A turbine ring assembly comprising a plurality of ring sectors forming a turbine ring and a ring support structure , each ring sector having, in a section plane defined by an axial direction (D A ) and a radial direction (D R ) of the ring and orthogonal to a circumferential direction (D C ) of the turbine ring , a part forming an annular base with, in the radial direction (D R ) of the turbine ring , an internal face defining the internal face of the turbine ring and an external face from which extend as projections a first and a second attachment tabs , the ring support structure including a central shell ring from which extend as projections a first and a second radial flanges to retain each ring sector , and an annular ring-flange having a free first end seated against the first attachment tab and a second end opposite to the first end and cooperating with the first radial flange , each ring sector extending between a first circumferential end and a second circumferential end each intended to face another adjacent ring sector in the circumferential direction (D C ), and comprising a first rectilinear seating surface positioned on an upstream face of the first attachment tab in contact with the annular ring-flange and a second rectilinear seating surface positioned on a downstream face of the second attachment tab in contact with the second radial flange , each of the first and second rectilinear seating surfaces extending along a tangent to the circumferential direction (D C ) between the first and second circumferential ends of the ring sector , characterized in that the rectilinear seating surfaces of each ring sector have, along said tangent to the circumferential direction (D C ), a variable thickness in the axial direction (D A ) with a minimum thickness at the first and second circumferential ends of the ring sector and a maximum thickness in a median portion of the rectilinear seating surface . the ring support structure including a central shell ring from which extend as projections a first and a second radial flanges to retain each ring sector , and an annular ring-flange having a free first end seated against the first attachment tab and a second end opposite to the first end and cooperating with the first radial flange , each ring sector extending between a first circumferential end and a second circumferential end each intended to face another adjacent ring sector in the circumferential direction (D C ), and comprising a first rectilinear seating surface positioned on an upstream face of the first attachment tab in contact with the annular ring-flange and a second rectilinear seating surface positioned on a downstream face of the second attachment tab in contact with the second radial flange , each of the first and second rectilinear seating surfaces extending along a tangent to the circumferential direction (D C ) between the first and second circumferential ends of the ring sector , characterized in that the rectilinear seating surfaces of each ring sector have, along said tangent to the circumferential direction (D C ), a variable thickness in the axial direction (D A ) with a minimum thickness at the first and second circumferential ends of the ring sector and a maximum thickness in a median portion of the rectilinear seating surface . <EOS>