Recent Advances in ASME Code Section XI Appendix K for Low Upper Shelf Toughness Evaluation
Bibliographic record
Abstract
Abstract The ASME Code Section XI Working Group on Flaw Evaluation members developed Appendix K to handle the assessment of low upper shelf materials dating back to extensive work done in the 1980s. Appendix K has remained basically unchanged since that time. A new version has been recently passed by the Code Committee which will be included in the 2025 Edition of the Code. This paper describes the changes that have been made to upgrade the materials characterization aspects as well as allowance for modern methods for transient definition and integrity assessment. The materials characterization definitions for the crucial J-integral resistance (J-R) curve have been broken into four areas: (1) an old correlation based on a database of J-R curves and material type, (2) addition of a new predictive methodology requiring measured Master Curve reference temperature T0 and its statistical correlation with a large database of J-R curve results based on the methodology in ASME Code Case N-830-1, (3) direct measurement of material J-R curves with requirements relative to the number of tests and applicability to neutron fluence conditions and test specimen orientation, test temperature, and material condition, and (4) other methodologies that can be reviewed by the regulator. One aspect that may still be added relative to the direct J-R curve measurement option is a test temperature minimum requirement for use when small fracture toughness specimens are tested with sizes less than a one-inch (25.4 mm) thick compact tension specimen [1T-C(T)]. Guidance or a cautionary note relative to the minimum test temperature for the testing of these smaller specimens is currently being discussed by the Code Committee.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.014 | 0.030 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.007 | 0.005 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.003 | 0.004 |
| Open science | 0.004 | 0.003 |
| Research integrity | 0.003 | 0.003 |
| Insufficient payload (model declined to judge) | 0.057 | 0.062 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".