Document: NUREG-0800
Document ID: 1f106a50-722f-45fa-952a-2e7ab7d836c1
Document Type: srp
Title: DYNAMIC TESTING AND ANALYSIS OF SYSTEMS, COMPONENTS, AND EQUIPMENT
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052360453.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.2
CFR Part: 
CFR Title: 

Content:
rum multidegree of freedom and time history methods form the bases for the analyses of all major Cate- gory I systems, components, equipment and their supports. When the modal response spectrum method is used, governing response parameters are combined by the square root of the sum of the squares rule. How- ever, the absolute sum of the modal responses are used for modes with 3.9.2-20 Rev. 2 - July 1981 closely spaced frequencies. The square root of the sum of the squares of the maximum codirectional responses is used in accounting for three components of the earthquake motion for both the time history and response spectrum methods. Floor spectra inputs to be used for design and test verifications of systems, components, equipment and their supports are generated from the time history method, taking into account variation of parameters by peak widening. A vertical seismic system dynamic analysis will be employed for all systems, and components, equipment and their supports where analyses show significant struc- tural amplification in the vertical direction. 3. The applicant has met the relevant requirements of General Design Criteria 1 and 4 with respect to the reactor internals being designed and tested to quality standard commensurate with the importance of the safety functions being performed and being appropriately pro- tected against dynamic effects by meeting the regulatory positions of Regulatory Guide 1.20 for the conduct of preoperational vibration tests and by having a preoperational vibration program planned for the reactor internals which provides an acceptable basis for veri- fying the design adequacy of these iTternals under test loading conditions comparable to those that will be experienced during operation. The combination of tests, predictive analysis, and post- test inspection provide adequate assurance that the reactor internals will, during their service lifetime, withstand the flow-induced vibra- tions of reactor operation without loss of