From the aspect of amplitude and energy of transmitted wave

the influence of incident angle and acoustic impedance ratio of SH waves on the vibration attenuation performance of soft interlayer is studied on condition that the medium is elastic and the reflected wave is neglected.Non-linear elasticplastic dynamic calculation is conducted to analyze the influence of the buried depth and thickness of the soft interlayer on the vibration attenuation performance.As a result

with the increase of incident angle

firstly the amplitude and the energy of the wave that transmits through the soft interlayer into the regular layer gradually increase and then rapidly decrease to zero.There exists a most unfavorable incident angle that is a function of velocity ratio and density ratio.When the SH wave incidents with the most unfavorable angle

no reflected wave occurs at the bottom and top of the soft interlayer

and the incident wave will totally transmit through the interlayer.The lower the acoustic impedance ratio of the soft interlayer to the regular layer is

the better the vibration attenuation performance of the soft interlayer is.However

the vibration of the soft interlayer will be more severe.In order to guarantee the damping effect of the soft interlayer

the critical buried depth of the soft interlayer increases with the wavelength of the incident wave.The damping effect will be the best when the buried depth is approximate to 20 percent of the wavelength of the shear wave in regular layer.It should be noted that the damping effect does not monotonously increase with the thickness of the soft interlayer.