Spatial incoherence of an earthquake ground motion may result in reduction in high-frequency components of the input motion for a building or a structure. Two-dimensional finite element method is used for heterogeneous soil medium. Through Monte Carlo simulation, the spatially correlated soil model shows more reducing effect in the average input with increasing frequency and with increasing correlation distance. Such effect is caused by the scattering damping and depends on the wavelength, the correlation distance, the traveling distance and the deviation of the soil properties.
