EVALUATING THE INTERACTION BETWEEN MULTIPLE IRREGULAR TOPOGRAPHIES DURING EARTHQUAKES

Soil layers and topographic irregularities can lead to amplification or attenuation of seismic waves. Such a phenomena have been theoretically explained in many researches by means of ground response analysis. Ground response analyses can properly satisfy the needs for realistic and precise seismic excitation in analysis of structures or in soil-structure interaction. In present study, two-dimensional Finite Element Method (FEM) is applied to evaluate the ground response of valley environments and estimation their interaction effects using time domain approach. In this regard three cases include free field condition, single valley and double valleys environments are considered. Numerical simulations of seismic wave propagation in these cases are carried out and compared with each other. The results show that irregular topography can greatly amplify the seismic waves. On the other hand, if there are adjacent topographies, due to interaction of them, this amplification effect can be substantially increased.

Keywords:

Ground response analysis , Two-Dimensional FEM , Valleys