Sensitivity analysis on seismic spatial variability parameters subjected to differential support motions
To explore the influences of the seismic spatial variability including incoherence effect,wave pas-sage effect and local site effect on the nonlinear time-history,based on the coherency function,the effects of shear wave velocity,site frequency,damping,incoherence coefficient on the spectral characteristics of seismic wave at the target point were studied,and the sensitivity analysis of the main parameters was carried out.The results show that the peak of the frequency response function for soft-medium and soft-firm soil layers occurs at about 1.5π Hz and is less than 1 after 2π Hz;the spatial correlation of seismic motion decreases gradually as the incoherence effect parameter increases from 0.1 ms/m to 1.0 ms/m;the spatial correlation of seismic mo-tion decreases gradually with distance from 100 m to 1 000 m;the phase difference exhibits increasing trends as the ratio of distance to apparent wave velocity increases from 0 to 1.The soft soil layer can amplify the low frequency and filter the high frequency;with the increase of incoherence effect parameter and distance,the spatial correlation of seismic motion decreases;the ratio of distance to apparent wave velocity determines the magnitude of phase difference.
seismic spatial variabilitywave passage effectlocal site effectincoherence effectsensitivity analysis
万方数据
维普
