Study of irregular behavior of shear waves in layered soil using matrix and finite element methods

This study uses both the theoretical matrix and finite element methods to simulate the three-dimensional (3D) wave propagation in elastic layered soils with a harmonic point load acting on the surface. Choosing different multi-layer cases (two, four and eight layers) where the point load is in horizontal or vertical direction, we first investigated the accuracy of the two methods, and the comparisons indicate that the results from both are in good agreement. Few authors have investigated the irregular wave amplitude of the Love wave induced in layered soils. This study indicates that the Love wave, unlike the Rayleigh wave, might generate larger ground vibrations for a wave located far away from the source, which is called wave hump in this paper. A ratio of the Young's modulus between the top and bottom soil layers larger than three may cause obvious this condition. Moreover, a layer thickness between 0.5 and 1.5 times the wave length in the first soil layer can significantly change the magnitude of the wave hump.