Behavior of Pressure-Induced Discontinuity Stresses at Elevated Temperature

Conventional wisdom has been that discontinuity bending stresses at temperatures within the creep regime are self-limiting, and therefore secondary. A series of creep relaxation analyses were performed on typical discontinuities (junctions). The analyses show that, in general, discontinuity bending moment and stress due to pressure do not relax, but remain more or less constant with time. These stresses should therefore be evaluated as primary. A creep follow-up mechanism was identified that sustains the discontinuity stresses. The implications for design are discussed.