RESEARCH ON THE ANISOTROPY OF THE COAL ROCK UNDER DIFFERENT BEDDING DIRECTION

Xiaohui Liu^{1, 2}, Feng Dai¹, Jianfeng Liu¹

¹College of Water Resources and Hydropower, Sichuan University, Chengdu, Sichuan, China, 610065

²College of Energy and Environment, Xihua University, Chengdu, Sichuan, China, 610039

The Fu Rong mining area was selected to analyse the micro view characteristics of the coal, the ultrasonic acoustic characteristics and the uniaxial compression feature from different directions (the parallel direction and the vertical direction). The results show that: (1) Coal rock has large discreteness with strong anisotropic properties. (2) The impulse wave velocities have obvious anisotropic characteristics. The parallel and vertical wave velocities are different. The parallel bedding velocity is greater than the vertical of coal rock no matter the longitudinal wave or transverse wave of coal rock. (3) The uniaxial compressive strength of parallel bedding coal rock is less than the vertical bedding of coal rock. The uniaxial compressive strength is normally distributed vertical wave velocity, obeying exponential functions or power functions. (4) Failure pattern of the coal rock in the parallel bedding direction is splitting, while the vertical bedding direction of coal rock is shearing. The uniaxial compression strength and deformation parameters in two directions are obviously different. In other words, the anisotropic is apparent.