Abstract:Taking acquired rock samples from real coal strata, processing them into two kinds of models (22 octahedrons and 2 icosahedrons) and tests in ultrasonic P wave and S wave have been carried out for these two kinds of models by pulse transmission technique.The analysis of tested results showed the existence of orientation-alighted fractures in coal samples produce distinguished anisotropy of velocity, S-wave splitting and anisotropy of attenuation,meanwhile,more obvious variation of dynamic feature of P-wave than kinematic feature is discovered and variation in attenuation of P-wave with fracture azimuths is more dis tinct than S-wave, which provided reliable experimental basis for using the variation of P-wave attributes to detect and predict the fractures.