Abstract:The variation of velocity and the absorption coefficient of waves in piles enclosed by soils with different Young modulus and damping coefficients are studied systematically by means of numerical analysis. It is shown that the wave velocity decreases with the decreasing of Young modulus and increasing damping coefficients;and the absorption coefficient increases with the increasing of Young modulus and damping coefficients. The absorption coefficient and wave velocity are approximately of negative linear correlation. The result of numerical calculation and measured data show that,when the excitation pulse width becomes bigger,the propagation velocity increases and the damping coefficients decrease. As the transmitting characteristics are different for pulses with different frequency components;the soils around the pile has the frequency dispersion and dissipation effect on the waves. The measured curve can be decomposed into different waveband components by wavelet analysis. The characteristics of dispersion and dissipation of soils to waves can be investigated by comparing the excited signal and the reflection curve.