Overview of US Efforts to Validate Analysis Methods and Design Criteria

摘要

As a part of its basic breeder reactor technology activities, the United States has a High-Temperature Structural Design Program aimed at establishing, and transferring to designers a rationally sound and experimentally validated structural design technology that will assure freedom from structural failures. Both development and validation efforts are centered on three main ingredients of the technology: (1) mathematical descriptions (constitutive equations) of the deformation behavior of the alloys of interest, (2) time-dependent rupture, or cracking, models, again for the alloys of interest, and (3) detailed design analysis methods and failure criteria based on these inputs. The objective of this presentation is to provide a brief overview of the status of efforts to experimentally assess and validate each of these three technology ingredients. In the case of deformation and rupture models, the current procedures and rules are outlined, and their significant features are assessed through comparisons with results from uniaxial and multiaxial material behavior tests. Design analysis methods and failure criteria are, on the other hand, discussed relative to the results of experimental benchmark structural tests. Although several significant needs and problem areas remain, data generated to date tend to provide limited validation of key aspects of the existing technology. Current constitutive equations represent many of the observed behavioral features; limited available data support current time-dependent rupture criteria reasonably well; and it is observed that structural analysis predictions capture most of the experimentally observed features of inelastic structural behavior. (ERA citation 04:046446)