【摘要】 基于近场地震记录频谱分析,结合地震危险性分析得到的基岩场地反应谱,进行了高山峡谷地区大型地下洞室群的人工地震动加速度时程的合成。该方法使用三角级数迭加法,利用攀枝花地震动记录进行傅里叶变换,得到离散点的傅里叶幅值谱,选择两个卓越频率作为控制傅里叶谱的峰值控制点,通过反复迭代生成了初始人工地震波,根据高山峡谷地形进行了深度修正、基线校正和高频滤波,最终生成了可以用于FLAC和ABAQUS等数值分析软件的人工地震动加速度-时程。数值分析表明,此方法拟合的人工地震波可以较好地反映不同频谱对地下洞室群强震响应的影响。更多还原

【Abstract】 The nonstationary seismic motion for large-scale underground cavern group located in alpine gorge is artificially simulated,based on the frequency analysis of near-site seismic log and bedrock response spectrum obtained by seismic hazard analysis.The trigonometric series superposition,under the control of two predominant frequencies by the Fourier transform of Panzhihua earthquake records,is used to simulate the seismic motion with consideration of depth modification,baseline modification and high frequency wave.The other earthquake log with similar geological background is also used to get the frequency spectrum if the near-site earthquake log is absent.The finished artificial seismic motions,as the numerical simulations show,fit the numerical analysis softwares such as FLAC and ABAQUS well.更多还原