Abstract
Ideal frequency dependent shear modulus and damping ratio characteristics are proposed through the analyses of vertical array several strong motion records by the parametric study. At first, FDEL and DYNEQ, equivalent linear methods developed to improve the disadvantage of SHAKE by considering frequency dependency of material property, are examined and are shown to overestimate amplification at high frequency range. Then frequency dependent functional shape is examined by optimizing the response. It is concluded that small amount of damping is necessary to suppress overestimation of amplification at high frequency, which corresponds scattering attenuation due to inhomogeneity of the ground. It is also pointed out that functional shape is better to be smooth. Optimized parameters give good result for both convolution and deconvolution analyses.
