Abstract
The stress redistribution locus (SRL) method has been proposed to provide a reasonable estimate for inelastic behavior employing elastic, elastic-plastic and⁄or elastic-creep FEM analyses. A theoretical and numerical analyses were carried out for a double and a single thick cylinder subjected to thermal transients, and the characteristics of SRL was investigated. When the stepwise temperature is raised inside an inner cylinder of the double thick cylinder model, the normalized equivalent stress-strains almost depict on the proposed SRL curve provided the ratio of the inelastic area to the inner cylinder remains below 30%. However when the temperature variation between both cylinders becomes to be greater, the normalized equivalent stress-strain curve leaves away from the proposed SRL curve. After analyses for the double thick cylinder model, inelastic behavior for the single thick cylinder model under a linear or a quadratic distribution of temperature was evaluated using elastic, elastic-plastic and elastic creep FEM analyses. Most normalized equivalent stress-strain loci draw nearly the same curve, and they are independent of temperature variations ΔT. Furthermore the SRL behavior is a bit depending on the configuration of temperature variation inside the cylinder but there is little influence on material properties and dimensions of cylinder. Thus it is verified that the present SRL procedure could estimate inelastic behaviors, and that its criterion guarantees the robust structural design for complicated components.
