Ground motion at a rock trapezoidal hill under seismic waves induced by an underground exploitation
Ground motion is unavoidably caused by seismic waves resulting from an underground explosion during underground energy and resource exploitation. The surface irregularities have significant influences on seismic wave propagation and cause amplification or reduction of ground motion. In current study, an analytical approach based on the geometric ray theory is presented to predict the ground motion at a trapezoidal hill under seismic waves induced by an underground explosion. The rock mass is assumed as a viscoelastic material with seismic quality factors, Q p and Q s . Based on the Kelvin model and the superposition principle, the particle velocity on the ground surface is obtained. The results from the present approach agree well with those from the existing method. Then, parametric studies are conducted. Effects of the rock material viscosity, the height of the trapezoidal hill, the frequency of incident wave and the rock elastic modulus on the ground motion are investigated. Eventually, a case is illustrated, that is, the incident P-waves, with frequencies from 20 Hz to 300 Hz, induce simultaneously ground motion on a slope surface of the trapezoidal hill.