离子型稀土原地浸矿采场滑坡全过程模拟的高阶双相物质点法研究

The mining benefit and safety of the ionic rare earth are seriously restricted by the in-situ leaching landslide that behaves large deformation and hydro-mechanical coupling features including the process of landslide’s generation, development, and stability. It is difficult for traditional numerical methods to effectively analyze the overall process of landslides. Material point method (MPM) possesses advantages of dealing with large deformation problems. However, it is difficult to represent the relative motion between the soil skeleton and pore fluid, and also suffers from the cell-cross error for the traditional material point method. In this project, a high-order two-phase material point method will be proposed and developed where the high-order B-spline basis function is used to replace the traditional linear basis function and two sets of material particle discretizations are introduced to simulate the interaction and relative motion of the soil skeleton and pore fluid in the leaching saturated rare earth. Evolution laws of physical and mechanical parameters of the ionic rare earth with the overall process of the in-situ leaching landslide will be determined by laboratory experiments. Based on the proposed method, overall processes of different ionic rare earth landslides induced by in-situ leaching will be simulated, and the validation of the proposed method will be checked by model tests. And then, the large deformation and hydro-mechanical coupling features of landslides will be clarified, and the failure mechanism of in-situ leaching landslides will be uncovered. This study will present an analysis method for explaining the overall process and hydro-mechanical coupling mechanism and provide a scientific basis for disaster assessment and prevention of in-situ leaching landslides.

原地浸矿采场滑坡严重制约着离子型稀土的开采效益和生产安全，其破坏机理涉及滑坡从产生、发展到稳定的大变形运动全过程及其水土耦合效应。传统数值方法难以有效分析采场滑坡的大变形运动，物质点法易于处理材料大变形，但难以表征水土两相介质的相对运动且存在网格穿越误差。本项目采用高阶次B样条基函数代替传统物质点法的线性插值形函数，基于水土两套物质点划分，建立考虑饱和土体固液两相介质相互作用和相对运动的高阶双相物质点算法。基于离子型稀土室内浸矿试验，明确在采场滑坡大变形破坏过程中稀土矿体物理力学参数的变化规律。采用高阶双相物质点法，对不同工况下的离子型稀土原地浸矿采场滑坡全过程进行模拟，通过模型试验确认算法有效性，进而阐明采场滑坡的大变形破坏规律和水土耦合效应，揭示采场滑坡的破坏机理。本项目为揭示离子型稀土原地浸矿采场滑坡全过程及其水土耦合机制提供一种有效分析方法，为采场滑坡灾害评估和防治提供科学依据。

原地浸矿采场滑坡严重制约着离子型稀土的开采效益和生产安全，其破坏机理涉及滑坡从产生、发展到稳定的大变形运动全过程及其水土耦合效应。传统数值方法难以有效分析采场滑坡的大变形运动，物质点法易于处理材料大变形，但难以表征水土两相介质的相对运动且存在网格穿越误差。本项目主要研究内容包括：（1）采用高阶次B样条基函数代替传统物质点法的线性插值形函数，发展了一种高精度B样条物质点法；（2）基于水土两套物质点划分，建立了考虑饱和土体固液两相介质相互作用和相对运动的高阶双相物质点算法。主要成果有：（1）基于离子型稀土室内浸矿试验，明确了在采场滑坡大变形破坏过程中稀土矿体物理力学参数的变化规律；（2）采用高阶双相物质点法，对不同工况下的离子型稀土原地浸矿采场滑坡全过程进行了模拟，阐明了采场滑坡的大变形破坏规律和水土耦合效应，揭示了采场滑坡的破坏机理。通过本项目研究为揭示离子型稀土原地浸矿采场滑坡全过程及其水土耦合机制提供了一种有效分析方法，为采场滑坡灾害评估和防治提供了科学依据。