Abstract: Ground fissure is a typical geologic hazard in loess field and the propagation law of seismic wave in ground fissure field is widely concerned in engineering world. To analyze the propagation law of seismic wave across ground fissure, the equivalent rigid coefficients of ground fissure in Xi’an field and discontinuous condition of fissure interface are selected. Considering the converted waves, frequency domain equations used to solve the transmission and reflection coefficients are obtained based on the fundamental solutions of the equation of motion. The influence of the incident angle, frequency of incident wave and medium parameters of ground fissure on the propagation law of seismic wave is analyzed. A brief conclusion from the results is obtained that ground fissure possesses the high-frequency filtering properties with the propagation of seismic wave. In low frequency condition, the transmission coefficient is more larger than others. Equivalent normal rigidity only influences the propagation of P-wave, but equivalent shear rigidity influences P-and SV-wave. Relative to equivalent normal rigidity, the influence of the changes of equivalent shear rigidity on transmission and reflection coefficients is more obvious.

Key words: Xi’an ground fissure, seismic wave, transmission and reflection coefficient, propagation law, wave motion theory