A method for creep-fatigue damage evaluation at structural discontinuity portions, (2)

Y-junction models based on a typical IHX support subjected to steady temperature distributions were analysed assuming elastic-fully-plastic materials. Though elastic follow-up parameters were found to increase with the load, the maximum value for the Y-junction corresponding to the typical IHX support was about 3.5 in the extent of FBR design. Types of inelastic behaviors could be classified with the comparison of two elastic follow-up parameters, one calculated assuming the type and the other calculated directly from nominal strains. Though the type was found to be influenced considerably by the corner radius of the acute side at junction, Y-junctions with ordinary geometrical profiles would be classified into TYPE II. (author)