Radial resistance controllable supporting structure suitable for large-deformation tunnel and supporting method

The invention discloses a radial resistance controllable supporting structure suitable for a large-deformation tunnel and a supporting method, and belongs to the technical field of tunnel engineeringconstruction. The structure comprises a primary spraying concrete layer, an inflatable cushion and a steel plate, wherein the primary spraying concrete layer is arranged on the surface of a surrounding rock in a tunnel, the inflatable cushion is fixed on one side of the steel plate, one side of the steel plate, provided with the inflatable cushion, is arranged close to the primary spraying concrete layer, an arch springing of the steel plate is fixed to the surrounding rock, the inflatable cushion is inflated to a safe pressure value, and a secondary lining is arranged on one side of the steelplate, which is not contacted with the inflatable cushion; the inflation cushion is provided with an inflation valve and a constant pressure deflation valve. According to the invention, the supporting structure can adapt to a