Considering nonlinear dynamic characteristics of soils by equivalent linearization method

site earthquake response analysis with horizontal-layered soil are analyzed on the basis of the one-dimensional wave motion model by SHAKE91 software

and we discussed the effects of the variability of soil dynamic parameters

including soil dynamic shear modulus ratio

damping ratio and shear velocity

on peak value of ground surface acceleration and its response spectra of deep soft sites. The conclusions are shown by using numerical results obtained from many case studies. The following combinations cause the most prominent effect on peak value of ground surface acceleration: the mean value of dynamic shear modulus ratio added by one standard deviation with the mean value of damping ratio reduced by one standard deviation; the mean value of dynamic shear module ratio reduced by one standard deviation with the mean value of damping ratio added by one standard deviation

but they cause negligible effect on the shape of the acceleration response spectra. And the 15% variability of shear velocity of strata makes more effect on the shape of the response spectra of ground surface acceleration. By comparison of calculation results

the variability of shear velocity of soil layers causes more prominent effect on the value of ground surface acceleration and its response spectra than the variability of dynamic shear modulus ratio and damping ratio do.