上游法尾矿坝渗透破坏和坝坡失稳的溃动机理及预测模型研究

The rainfall-reservoir water level fluctuation are the important controlling factors of dam stability in the lifetime service period of tailings dams. The previously main research objects were the disaster-causing mechanism of static tailings dam, and the domestic and overseas scholars had neglected substantially the contribution of reservoir water level fluctuation on the dam debacle in the.dynamic damming of tailings dam. To take the common diseases "seepage failure" and "dam instability" of upstream tailings dam as the research objects, the indoor experiment, model experiment, numerical simulation and theoretical analysis were adopted to carry out the researchs. The project would analyze the seepage variation law of stratified dam under the rainfall-reservoir water level fluctuation, and reveal the structure degradation and strength attenuation law of tailings, and build the multi-medium and multi-factor coupling mechanics model of tailings materials. Through the real-time observation with the macroscopic phenomenon of dam break and change characteristics of soil internal parameters, the basic laws and disaster characteristics of static and dynamic transformation before and after buckling failure would be explored under the rainfall-reservoir water level fluctuation. With the statistical regression method and classical soil mechanics theory, the critical discriminant of buckling failure would be established in the dynamic damming of tailings dam under the rainfall-reservoir water level fluctuation. The project would build the dam break prediction model of tailings dam with the accumulative mechanical conditions of step-by-step damming under the rainfall-reservoir water level fluctuation. On this basis, the VC++ would be used to achieve the model visualization and some typical accidents of tailings dam would be analyzed to validate and amend prediction model. The research results could provide reference for the disaster warning of tailings dam.

降雨-库水位变动是尾矿坝服役期内稳定与否的重要控制因素，目前国内外学者主要针对降雨下静态尾矿坝的致灾机理开展研究，却实质性忽略了库水位变动对动态筑坝过程中尾矿坝溃动构成的贡献。本项目针对上游法尾矿坝常见病害“渗透破坏”及“坝坡失稳”，采用室内实验、模型实验、数值模拟及理论分析等方法开展研究，寻求降雨-库水位变动下分层坝体的变化渗流场，揭示尾矿散体组成结构劣化及强度衰减规律，建立多介质多因素影响下的尾矿耦合力学强度模型，通过实时观测尾矿坝宏观溃动现象及土体内部参数变化特征，探索坝体失稳破坏前后静动力转化的基本规律，利用统计回归方法和经典土力学理论构建基于降雨-库水位变动条件下动态筑坝的尾矿坝溃坝临界判别式，提出降雨-库水位变动下逐级堆坝累加力学条件的尾矿坝溃坝预测模型，运用VC++语言实现该预测模型的可视化，通过模拟典型尾矿坝溃坝事故修正预测模型，研究成果可为尾矿坝的防灾预警提供参考。

降雨-库水位变动是尾矿坝服役期内稳定与否的重要控制因素，目前国内外学者主要针对降雨下静态尾矿坝的致灾机理开展研究，却实质性忽略了库水位变动对动态筑坝过程中尾矿坝溃动构成的贡献。本项目针对上游法尾矿坝常见病害“渗透破坏”及“坝坡失稳”，采用室内实验、模型实验、数值模拟及理论分析等方法开展研究，通过典型尾矿材料的土柱实验和库水变动渗流土箱实验，探讨了降雨-库水位变动下尾矿材料的渗流特性；通过XRD及XRF实验测定了化学溶液作用下典型尾矿材料的成分及其物相含量，并借助SEM技术分析了长期浸泡下尾矿颗粒粒径、颗粒孔隙率、颗粒几何形状等物理特性变化规律，探索了典型尾矿材料在化学溶液作用下的微观结构及组成变化，揭示了长期浸泡作用下典型尾矿散体组成结构劣化及强度衰减机理，建立了多因素影响下的尾矿耦合力学强度模型；开展了全面降雨、库内降雨和库内水位变动条件下的尾矿坝溃坝模型实验，通过实时观测尾矿坝宏观溃动现象及土体内部参数变化特征，探索了坝体失稳破坏前后静动力转化的基本规律，利用统计回归方法和经典土力学理论构建了基于降雨-库水位变动条件下动态筑坝的尾矿坝溃坝临界判别式，提出了降雨-库水位变动下的尾矿坝溃坝预测模型，并将该预测模型可视化，研究成果可为尾矿坝的防灾预警提供参考。