煤矸石压缩试验的颗粒流模拟

 根据煤矸石颗粒材料的特点，采用三维颗粒流方法PFC3D的接触连接本构模型模拟煤矸石的压缩特性，再现其复杂的非线性本构关系。设计单一级配和泰波理论级配方案，并用Fish语言生成级配颗粒模型。对煤矸石的三轴压缩试验过程进行数值模拟，比较不同围压下的应力–应变曲线、体积应变曲线和微裂纹发展曲线，从细观角度验证不同级配煤矸石试样的强度及变形规律。研究结果显示，优化的级配方案能提高矸石的峰值强度，降低其压缩量，这对优化矸石充填的级配设计有一定的参考价值。

SIMULATION OF COMPRESSION TEST ON GANGUE BY PFC3D

Based on the characteristic of gangue，a PFC3D model with contact-bond nonlinear constitutive behavior is established to simulate the triaxial compression tests of gangue. Different gradation projects of particle assembly are designed on the basis of Talbot?s theory；and gradation particle model is generated by using Fish language. The numerical simulation of triaxial compression test of gangue is conducted. The stress-strain curves，volumetric strain curves and microcracks propagation curves under different confining pressures are compared to verity the strength and deformation regulations of gangue with different gradations from mesoscopic view. The study result shows that optimal gradation of particles will improve the peak strength of gangue assembly and decrease its compressibility. The simulation results would be helpful for the optimal design of gangue backfill material in coal mining.