Thermal ratchetting of a clamped circular plate subjected to steady transverse pressure and cyclic radial temperature variation

The shakedown limit for a clamped circular plate subjected to steady transverse pressure load and cyclic radial temperature variation is obtained from finite element elastic-plastic solutions. This computed limit is compared with an upper bound solution which proves to be very unsafe. Two very different ratchetting mechanisms were identified; one is dominantly flexural and involves large incremental deformation; the other mechanism is associated with very small incremental deformation within the cyclic plasticity zone which develops when the thermal loads are large. The design implications of the solutions are discussed. (orig.)