采场中充填体的几何结构和力学特性是影响充填体质量的控制性因素。通过开展充填料浆流动沉降相似模拟试验及充填体单轴和常规三轴压缩试验，揭示采场充填体的结构特征与强度分布规律，研究不同围压下不均匀充填体的变形特征与破坏模式。结果表明，（1）采场内充填体存在两个分界面和粗骨料、细骨料及灰砂3个不同区域，沿充填料浆流动方向，充填体的强度呈减小 – 增加 – 减小的“S”型分布；（2）充填体三轴压缩轴向应力–应变曲线包括压密、弹性、屈服、应变软化、残余强度5个阶段，相同区域充填体的强度随围压增加而上升，相同围压下不同区域的充填体强度大小依次为灰砂区域>细骨料区域>粗骨料区域。不同区域充填体的黏聚力大小依次为灰砂区域>细骨料区域>粗骨料区域，内摩擦角大小依次为粗骨料区域>细骨料区域>灰砂区域；（3）随围压的增大，充填体宏观破坏裂纹呈增多的趋势，宏观破坏主要为单斜面剪切破坏、张剪复合破坏和“Y”型破坏3种破坏形态。研究成果能为采场的充填钻孔数量与位置设计及稳定性分析提供理论依据。

The geometrical structure and mechanical characteristics of backfill body are factors influencing the quality of filling material. In this study, similar simulation tests were conducted to investigate flow sedimentation law of filling slurry; uniaxial and triaxial compression tests on backfill body samples were carried out to reveal the structural characteristics and strength distribution law of backfill body, and to capture the deformation characteristics and failure mode of uneven backfill body samples under different confining pressures. The results show that: (1) Two boundaries and three areas of coarse aggregate, fine aggregate, cement-tailing exist in backfill body in stope. The strength of backfill body samples has an “S” distribution of diminution-enlargement-diminution along the flow direction of filling slurry. (2) Stress-strain curves of backfill body samples under triaxial compression are composed of five stages of the compaction, i.e. the elastic, the plastic, the post-yielding, the strain softening and the residual stress stages. The strength of backfill body samples in the same area increase with the increase of confining pressure. The strength of backfill body samples in different areas under the same confining pressure is in the order as cement-tailing area > fine aggregate area > coarse aggregate area. The cohesion of backfill body samples in different areas is in the order as cement-tailing area > fine aggregate area > coarse aggregate area, and the internal friction angle is in the order as coarse aggregate area > fine aggregate area > cement-tailing area. (3) The quantity of macro-failure cracks of backfill body samples is on the up-trends as the confining pressure increases, the main macro-failure modes are shear failure of single ramp, tension-shear failure, Y-shaped shear failure. The results can provide theoretical basis for the design of the amount and position of drill holes for filling, also provide theoretical basis for stability analysis of filling material.