Document: NUREG-0800
Document ID: 6b7eddf4-f7ce-4821-9f11-e37070221e57
Document Type: srp
Title: DYNAMIC TESTING AND ANALYSIS OF SYSTEMS, STRUCTURES, AND
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1613/ML16133A418.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.2
CFR Part: 
CFR Title: 

Content:
using the maximum stress amplitude should be calculated. The choice of analysis approach (time or frequency domain) should be substantiated, confirming that conservative analysis results are obtained, along with the acceptability of damping modeling (such as the Rayleigh damping method used for time domain calculations). If Rayleigh damping is used, the ‘anchor frequencies’ should be chosen appropriately to ensure that conservative damping is applied over all important frequencies. For cases where a single frequency dominates the response, or where the frequencies of the applied forces are well below the first resonance frequency of a loaded structure, reporting may be limited to RMS or peak values. (ii) Benchmarking of analysis methodologies, particularly end-to-end benchmarking using previous testing on prototypes, should be 3.9.2-24 Revision 4 – March 2017 substantiated. If individual bias errors and uncertainties of the various modeling components (including structural and forcing function) are combined into approximate end-to-end values, they should be checked to ensure that the predictions bound the measurements in the end-to-end comparisons. Any non-conservative differences should be quantified for their potential impact on structural integrity and fatigue life. When frequency spectra are benchmarked, frequency dependent bias errors and uncertainties need to be reported. More details on acceptable benchmarking methods are available in RG 1.20, Revision 4, Section C.2.1.3.1. (iii) Structural Evaluation (1) Structural Model Development and Stress Convergence For structural analysis, a verified finite element computer code needs to be employed. Modeling of reactor internal structures typically entails the use of solid, plate/shell, and beam elements. Connecting plate/shell elements and beam elements to solid elements involves special modeling techniques to ensure rotational compatibility and moment transfer. Various techniques have been developed and