Numerical Evaluation of the Amplification Characteristic of Randomly Heterogeneous Alluvial Deposits

Abstract

The estimation of the local site effects, which is inherently stochastic, on the amplitude and the frequency content of seismic wave through alluvial deposits, is an important and substantial step in the seismic risk mitigation. To this end, the random field theory along with the Monte Carlo simulations was employed to evaluate ground response of a half-space viscoelastic medium under stochastic variation of the shear wave velocity (SWV) adopted from five different sites. The results of the stochastic analyses are then compared to the deterministic computations assuming hyperbolic variation of SWV. This study will emphasize the importance of the stochastic variation of the shear wave velocity profile. An eminent input from the current study is that the sole consideration of the deterministic component in site response analyses is not well representative of the real seismic behavior of the alluvial deposits.