Investigation of stress-induced progressive failure of mine pillars using a Voronoi grain-based breakable block model  

作　　者：Shili Qiu Shirui Zhang Quan Jiang Shaojun Li Hao Zhang Qiankuan Wang 

机构地区：[1]State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《International Journal of Mining Science and Technology》2024年第5期713-729,共17页矿业科学技术学报（英文版）

基　　金：the National Natural Science Foundation of China(No.42377172);the National Key Research and Development Plan Project of China(No.2023YFC2907204).

摘　　要：The Voronoi grain-based breakable block model(VGBBM)based on the combined finite-discrete element method(FDEM)was proposed to explicitly characterize the failure mechanism and predict the deformation behavior of hard-rock mine pillars.The influence of the microscopic parameters on the macroscopic mechanical behavior was investigated using laboratory-scale models.The field-scale pillar models(width-to-height,W/H=1,2 and 3)were calibrated based on the empirically predicted stress-strain curves of Creighton mine pillars.The results indicated that as the W/H ratios increased,the VGBBM effectively predicted the transition from strain-softening to pseudo-ductile behavior in pillars,and explicitly captured the separated rock slabs and the V-shaped damage zones on both sides of pillars and conjugate shear bands in core zones of pillars.The volumetric strain field revealed significant compressional deformation in core zones of pillars.While the peak strains of W/H=1 and 2 pillars were relatively consistent,there were significant differences in the strain energy storage and release mechanism.W/H was the primary factor influencing the deformation and strain energy in the pillar core.The friction coefficient of the structural plane was also an important factor affecting the pillar strength and the weakest discontinuity angle.The fracture surface was controlled by the discontinuity angle and the friction coefficient.This study demonstrated the capability of the VGBBM in predicting the strengths and deformation behavior of hard-rock pillars in deep mine design.

关 键 词：Pillar strength FDEM Voronoi tessellation SPALLING BULKING 

分 类 号：TD632[矿业工程—矿山机电]