边坡与地下开采耦合作用下岩体响应的演化特征及其动态效应研究

The slope and rock mass around the bottom and underground mining form a complex dynamic system for mine that is transferred to underground mining. It’s deformation and mechanical behavior is very complicated，and it shows a typical nonlinear characteristics in some areas. Taking the open-pit of slowly inclined thin to thick phosphate rock bed contains soft interlayer to underground mining with room-and-pillar method as the basis，relying on the synthetic study achievement of field investigation，simulated experiment with analogy material，numerical simulation analysis and theoretical research，the complete dynamic evolution characteristics of stress field，displacement field，deformation and damage field of layered soft-rock and high-steep slope，underground stope wall rock and the overlying rock mass will be studied，and the slope height and slope angle effects for underground mining will be emphatically illuminated. Then the phased characteristics mechanical analysis model with the consideration of the effector molecule K of open pit slope will be established for the overlying key rock strata，the evolving equations of mining deformation will be established also，and the mechanical condition criterion of mining instability will be put forward，by the correlation theories containing the elastic-plastic theory of rock mass，Reissner medium-thickness plate theory and transforming mathematical method. At last，these above research findings helps to reveals the interaction nonlinear-deformation mechanism and dynamic instability mechanism of the slope and underground mining，and achievements provide a scientific basis for ground pressure management and control and slope security maintenance of transition from open pit to underground mining with complex geological occurrence conditions.

矿山由露天转地下开采后，边坡及坑底周围岩体与地下开采组成一个复合动态变化体系，其变形和力学行为极为复杂，局部呈现出典型的非线性特征。本项目以缓倾斜含软夹层薄至中厚磷矿床露天转房柱法地下开采为依托背景，拟在现场调研、相似材料模拟试验、数值模拟分析与理论研究的基础上，研究露天层状高陡岩质边坡与地下采场围岩及其上覆岩体应力场、位移场及变形破坏场的动态演化特征，阐明边坡对地下开采的坡高、坡角影响效应。基于岩体弹塑性理论、Reissner中厚板理论，运用数学化归分析法，引入边坡效应因子K，构建地下采场上覆关键层分阶段特征的力学分析模型及岩体变形破坏演化的形态方程，提出岩体采动失稳的力学条件判据，揭示露天层状高陡岩质边坡与地下开采耦合作用下岩体响应的非线性变形机制与动态失稳机理，为复杂地质赋存条件矿山露天转地下开采后地压管理与控制及露天边坡的安全维护提供科学依据。

矿山由露天转地下开采后，边坡及坑底周围岩体与地下开采组成一个复合动态变化体系，其变形和力学行为极为复杂，局部呈现出典型的非线性特征。本项目以云南滇池周边典型的缓倾斜含软夹层薄至中厚磷矿山晋宁磷矿露天转房柱法地下开采为工程背景，借助BBX3系列三目相机及1080P的高清摄影系统相结合的测试手段，采用现场调研、室内大型平面相似材料模拟试验、Madem数值模拟分析与理论研究的综合研究手段，系统研究了不同坡高与坡角条件下，露天转地下开采后，层状高陡岩质边坡、地下采场围岩及其上覆岩体的应力与变形破坏规律。通过形态、数量、密度、尺寸大小、分布范围、空间位置、岩体移动角与破坏角等指标半定量描述岩体变形与采动裂隙的几个重要阶段的演化，构建了露天转地下后采动岩体变形破坏带外轮廓线的形态方程。最后基于弹塑性力学理论、矿压理论与 Reissner 岩板理论，结合试验研究结果，引入露天终了边坡效应因子K，构建边坡影响下地下采场上覆关键层“改进的Reissner中厚板”力学分析模型，并对其失稳力学条件判据进行分析，揭示了露天转地下开采后层状高陡岩质边坡与地下开采耦合作用下岩体非线性变形机制与动态失稳机理，为复杂地质赋存条件矿山露天转地下开采工程提供理论依据。