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:
the presence of flow-excited acoustic resonances. These pressure pulsations are used in some inverse analysis 3.9.2-28 Revision 4 – March 2017 methods to define the dryer loading function, the dryer dynamic response and the resulting alternating stresses. Alternating stresses caused by mechanical loads from RRP VPF tones should be quantified based on test data. Additional guidance on direct, as well as remote (via MSL strain gage arrays) dryer stress monitoring is available in RG 1.20, Revision 4. 5. For requirements of GDCs 2, 4, 14, and 15, dynamic system analyses should confirm the structural design adequacy of the reactor internals to withstand the dynamic loadings of the design-basis LOCA in combination with the SSE. Where a substantial separation between the forcing frequencies of the LOCA (or SSE) loading and the natural frequencies of the internal structures can be demonstrated, the analysis may treat the loadings statically. Evaluations performed under SRP Section 3.6.3 address review of applications that propose to eliminate consideration of design loads of the dynamic effects of pipe rupture. Evaluation in this section should interface with the evaluation in Section 3.6.3. The most severe dynamic effects from LOCA loadings generally result from a postulated double-ended rupture of a primary coolant loop near a reactor vessel inlet or outlet nozzle with the reactor in the most critical normal operating mode. However, all other postulated break locations should be evaluated and the location producing the controlling effects should be identified. Mathematical models used for dynamic system analysis for LOCAs in combination with SSE effects should include the following: A. Modeling should include reactor internals and dynamically-related piping, pipe supports, components, and fluid-structure interaction effects when applicable. Typical diagrams and the modeling basis should be developed and described. B. Mathematical models should typify system structural