Vertical wave barriers for vibration reduction

Abstract

Earthquakes generate a series of waves that penetrate the Earth. Depending on proximity to the epicenter of an earthquake, different types of seismic waves dominate at the surface of the Earth. Distinct kinds of seismic waves shake the ground in various ways. Love and Rayleigh waves both produce ground shaking at the surface of the Earth, which exponentially attenuates with depth. Surface waves can often constitute the most important component of ground shaking far from the epicenter due to the fact that the decrease in their amplitude diminishes less rapidly with distance; thus, these waves can be dangerous and destructive. Hereinafter, the concept of a seismic barrier in soil protecting the area from seismic waves of the Rayleigh type is considered. The main idea behind this type of protection is to prevent seismic waves from transmitting wave energy into the protected zone, decreasing the amplitudes of displacements, velocities and accelerations at the points behind the barrier. In this article, numerical simulations on planar and spatial models are presented and discussed for the cases of horizontal and vertical barriers using different mechanical and geometrical parameters of the barriers. Additionally, an algorithm for a multi-parametric optimization of the barrier geometry and material is presented and adopted for specific soil conditions.