Document: NRC Regulatory Guide
Document ID: aa450282-f5b0-4dd2-b41a-917a7491deb2
Document Type: regulatory_guide
Title: Preparing Probabilistic Fracture Mechanics (Rev. 0)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2133/ML21334A158.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.245
CFR Part: 
CFR Title: 

Content:
ith the relevant subject area could independently implement the model(s) from the documentation alone. Model forms can either be theoretical, semiempirical, or empirical. • Establish a basis for all significant aspects of the model(s). This may consist of raw data or published references. Document or reference any algorithms or numerical methods (e.g., root-finding, optimization) needed to implement the model(s). Discuss any significant assumptions, approximations, and simplifications made, including their potential impacts on the analysis. • Identify important uncertainties or conservatisms. • Describe the computational expense of the model and how that might affect analysis choices. M-5 First-of-a-kind model not yet published in a peer-reviewed journal • See the submittal guidelines for M-4, and perform and document model sensitivity studies to understand trends in the model, as compared to expected model behavior and to the data used to develop the model, and describe model maturity and the status of the technical basis. RG 1.245 Revision 0, Page 16 2.6. Inputs For each QoI, the applicant should categorize each input in the PFM software or analysis as shown in Table C-4. In Table C-4, “knowledge” refers to the depth of information available to prescribe either the deterministic inputs or the distributions on the uncertain inputs. “Importance” refers to the relative effect of input on the QoI. To determine the input category, the applicant should consider the following: • whether the input is deterministic or uncertain, • how much knowledge is available about the input, and • the input’s importance with regard to the QoI. Throughout the analysis, the applicant should continuously assess the relative importance of inputs on the QoI and revisit the assumptions and choices made for the most important inputs to confirm their validity. The applicant should also consider the use of sensitivity studies to show the impact (or lack thereof) of some