Hilbert-Huang transform (HHT) analysis on the response of seismic waves to the different decoupling coefficient

In order to obtain the law of the seismic wave quality to the coupling coefficient and explore the excitation of high-energy, high-frequency seismic waves in the optimal coupling. Four different coupling coefficients (1.00, 1.33, 1.67, 2.50) dynamite source selected to test in shallow soil. And use the Hilbert-Huang transform (HHT) to analysis the vibration velocity dynamite source signals of the surface in the 10-60 m range. The results showed: seismic coupling charge generated by way of dynamite source at a distance closer to the source of the explosives (within 15 m range) seismic wave energy charge is significantly higher than the other three different coupling coefficient. But as the distance increases, the energy decreases fastest, after the focal distance of dynamite 15 m, the seismic wave energy is less than coupling coefficient of 1.33 and 1.67 seismic wave energy; The seismic wave energy decreases with the decline of the coupling coefficient. Seismic coupling charge of explosive charge generated highest frequency in the way of the focal distance of 30 m, but the frequency of maximum attenuation coefficient, more than 30 m after its frequency is not less than the coupling coefficient of 1.33 and 1.67 of dynamite source charge way.