Shakedown and Ratcheting Analyses of Fusion Reactor First Wall

Bree diagrams are developed for shakedown and ratcheting analyses of a typical fusion reactor first wall subjected to cyclic thermal and steady primary stresses. The stresses are assumed to be predominantly of the bending type. The first loading/unloading cycle is analyzed analytically as well as numerically using elasticplastic beam bending theory. The general problem of elastic shakedown is solved using the shakedown theorem of perfect plasticity. The problem of plastic strain cycling with and without ratcheting is solved using numerical analysis.