Radial turbomachine, comprising: a fixed case; at least one rotor disc (2, 2', 2") installed in the case and having rotor blades (3, 3', 3") mounted at least on a front face (4, 4', 4") thereof, in which the rotor disc (2, 2', 2") is rotatable in the case around a respective rotation axis (X-X); a plurality of elements (25, 35) projecting from the case and terminating in proximity to the rotor disc (2, 2', 2"), wherein the projecting elements (25, 35) comprise seal elements acting against the rotor disc (2, 2', 2") and operatively active on a rear face (9, 9', 9") of the rotor disc (2, 2', 2") and/or wherein the projecting elements (25, 35) comprise stator blades radially interposed between the rotor blades of the rotor disc; at least one support plate (17, 37) installed in the case; wherein said support plate (17, 37) bears said elements (25, 35) projecting from the case; wherein said at least one support plate (17, 37) is radially extended across from the rotor disc (2, 2', 2"); characterized in that the support plate (17, 37) comprises: a plurality of first circular portions concentric with the rotation axis (X-X), wherein at least some of said first circular portions bear said projecting elements (25, 35); a plurality of second circular portions radially interposed between the first circular portions; wherein the second circular portions are more deformable, along radial directions, than the first circular portions in a manner so as to allow relative movements between the first circular portions when the support plate (17, 37) is subjected to the action of thermal gradients. a fixed case; at least one rotor disc (2, 2', 2") installed in the case and having rotor blades (3, 3', 3") mounted at least on a front face (4, 4', 4") thereof, in which the rotor disc (2, 2', 2") is rotatable in the case around a respective rotation axis (X-X); a plurality of elements (25, 35) projecting from the case and terminating in proximity to the rotor disc (2, 2', 2"), wherein the projecting elements (25, 35) comprise seal elements acting against the rotor disc (2, 2', 2") and operatively active on a rear face (9, 9', 9") of the rotor disc (2, 2', 2") and/or wherein the projecting elements (25, 35) comprise stator blades radially interposed between the rotor blades of the rotor disc; at least one support plate (17, 37) installed in the case; wherein said support plate (17, 37) bears said elements (25, 35) projecting from the case; wherein said at least one support plate (17, 37) is radially extended across from the rotor disc (2, 2', 2"); characterized in that the support plate (17, 37) comprises: a plurality of first circular portions concentric with the rotation axis (X-X), wherein at least some of said first circular portions bear said projecting elements (25, 35); a plurality of second circular portions radially interposed between the first circular portions; wherein the second circular portions are more deformable, along radial directions, than the first circular portions in a manner so as to allow relative movements between the first circular portions when the support plate (17, 37) is subjected to the action of thermal gradients. a plurality of first circular portions concentric with the rotation axis (X-X), wherein at least some of said first circular portions bear said projecting elements (25, 35); a plurality of second circular portions radially interposed between the first circular portions; wherein the second circular portions are more deformable, along radial directions, than the first circular portions in a manner so as to allow relative movements between the first circular portions when the support plate (17, 37) is subjected to the action of thermal gradients.