核电厂楼面反应谱的人工合成地震动时程方法对比分析

Comparison of Methods for Artificial Earthquake Time History Matching Floor Response Spectra in Nuclear Power Plants

为满足核电厂核岛内部结构、系统和部件(SSCs)的抗震分析需求,采用2种典型算法(频域调幅法和时域叠加法)来合成匹配核岛内部楼面反应谱的人工时程。通过算例分析,对比2种算法在反应谱匹配精度、时程非平稳特性、相位、基线漂移等方面的优缺点及其与美国核管理委员会(NRC)颁布的标准审查大纲(SRP)第3.7.1节要求的符合性。结果表明:在反应谱匹配精度(特别是多阻尼反应谱)、时程非平稳特性的改变、基线漂移的控制上,时域叠加法均优于频域调幅法;但频域调幅法可较完整地保留种子时程的相位信息,适合于SRP 3.7.1对时程相位有特殊要求的分析。

In order to satisfy the requirements of seismic analysis for the structure, system and components （SSCs） in Nuclear Power Plants （NPPs）, two typical methods （modify the Fourier amplitude spectra in frequency domain and superimposing wavelet in time domain） were used to generate the artificial time history matching the Floor Response Spectra in NPPs. Numerical examples demonstrate that the time domain method is better that the frequency domain method in the matching precisions to the target spectra （especially the multi-damping spectra）, preserving the nonstationary character and baseline drift correction. However, the frequency domain method can maintain the phasing of Fourier components of the initial seed time history, which meets the requirements of the nonlinear structural analysis problems in SRP 3.7.1.