Document: NUREG-0800
Document ID: 6171d065-38ce-4cde-aa53-058baf32948a
Document Type: srp
Title: 2.82
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1419/ML14198A460.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.16
CFR Part: 
CFR Title: 

Content:
2.54 2.32 1.90 1.65 1.09 0.94 25.60 2.39 2.21 1.63 1.44 1.27 1.10 0.96 0.67 0.45 0.40 32.00 1.37 1.25 0.90 0.76 0.66 0.56 0.54 0.39 0.23 0.20 40.00 0.85 0.80 0.57 0.47 0.41 0.33 0.33 0.24 0.16 0.12 50.00 0.60 0.56 0.37 0.36 0.30 0.24 0.25 0.19 0.11 0.090 62.50 0.51 0.48 0.32 0.31 0.24 0.20 0.23 0.16 0.10 0.078 78.13 0.50 0.46 0.32 0.29 0.24 0.20 0.23 0.16 0.10 0.077 97.66 0.50 0.46 0.32 0.29 0.24 0.20 0.23 0.16 0.10 0.077 3.7.1-32 Revision 4 – December 2014 B.1 Development of Target PSD for Bin Representative Response Spectra (RS) To develop each target PSD in Tables 1 and 2 for the NUREG/CR-6728 bin representative design response spectra (RSrep), as defined by Equations (2) and (3), an iterative frequency-by- frequency scaling approach was applied. The initial PSD value was taken as the bin average PSD for the NUREG/CR-6728 time history database (Tables 3 through 6 of Appendix B show the bin average PSD and Tables 7 through 10 show the bin average RS). Ten iterations were found to be adequate to produce a target PSD compatible with the bin representative RSrep. The iterative process consists of the following four steps: (1) Generate M number of synthetic time histories from the current PSD function, where M took a value of 10, 20, … 100 for iteration 1, 2, …10, respectively. To generate synthetic time histories from a PSD function, (a) Fourier spectra were constructed by utilizing random phase angles and Fourier magnitudes computed following Equation (1), and (b) time histories were then generated through inverse FFT. The synthetic time histories were assumed to have 4096 data points and a time step of 0.005 s. Since the synthetic time histories are stationary at this point (the envelope function is applied in step (2) below), the entire duration of 20.48 s was used to generate the Fourier spectrum using Equation (1). The PSD function was linearly interpolated in the log-log scale to fill all frequency points for the Fourier coefficients. This method produces