Dynamic Behavior of Coal Pillar Under Different Load Percentage by Numerical Simulation

Abstract The stability and dynamic response of coal pillar is of great importance in underground coal mining. In this paper, a series of uniaxial compressiveexperimentswerefirst carried out to investigate the mechanical properties of coal. Subsequently, a statistical constitutive damage model for coal was proposed and applied to the numerical simulation. The proposed strain damage softening function showed almostthe same goodness-of-fit on the experimental curve. A numericalmodel FLAC3Dwas created to investigate the dynamic behavior of the coal pillar under different load percentage(LD). Modelling suggests that the incident and transmitted wave stress evolution observesa similar rule and its process can be divided into three stages, namely, static preload, dynamic disturbance and stabilized stages.Under the same load percentage, the peak incident and transmitted wave stress increase with the increase of dynamic disturbance intensity. On the contrary, the attenuation decrease. It is also observed that the failure zone interior the coal can be predicted by the wave propagation.