动-静载作用下尾矿库稳定性及溃决尾砂大变形运移机制研究

The safe stockpiling and disposal of solid waste in mines is an important requirement to guarantee mine security and “green mine” development. However, previous studies of the disaster mechanism of tailings ponds based on stability evaluation and safety monitoring often ignored the rheological and consolidation effects of the stockpiling tailings, and limited the systematic research on the “erosion effect” of outburst tailings. In the paper, for the important scientific problem of “tailings dynamic/static force stability evolution law” and “large deformation movement-mechanical response mechanism of outburst tailings”, with the stockpiling (lead and zinc) tailings as the research object, the relationship between the macroscopic and mesoscopic characteristic parameters of tailings under the consolidation effect was clarified through macroscopic and mesoscopic experiment as well as numerical simulation method. Besides, the three-dimensional constitutive relation of fluid-structure coupling was established. On the basis, the mechanical response of the stockpiling tailings under the coupled action of earthquake and consolidation was explored. And the dynamic/static stability evolution law and coupling law were expounded. At the same time, physical model experiment and large deformation movement simulation based on smooth particle hydrodynamics method were used to study the movement characteristics of outburst tailings flow and its impact effect on rigid body, so as to reveal the time-history law of the movement and impact effect of tailings under multi-mode. The research not only contributes to the systematization of the basic theory of the disaster mechanism of tailings pond dam break, but also has important strategic significance for promoting the safe and green disposal of mine solid waste and the development of mine safety in China.

矿山固废的安全堆存与处置是国家保证矿山安全和“绿色矿山”发展的重大需求。以往基于稳定性评价、监测等尾矿库致灾机制研究，常忽略了堆存尾矿流变和固结效应、限制了溃决尾砂“侵蚀效应”等体系化研究。针对“尾矿库动/静力稳定性演化规律及其耦合关系”和“溃决尾砂大变形运动-冲击效应机理”科学问题，以堆存（铅锌）尾矿为研究对象，采用宏、细观实验与数值模拟结合的手段，厘清固结效应下堆存尾矿宏、细观特征参量的关系，建立其流固耦合三维本构关系；在此基础上，研究地震与固结耦合作用下堆存尾矿动力响应，阐明动/静力稳定性演化与耦合规律；最后，采用物理模型实验与基于光滑粒子流体动力学（SPH）的大变形运动模拟，探析溃决尾砂流运动特征及对刚体的冲击效应，揭示多模式下尾砂运动-冲击效应机理。这一研究不仅有助于尾矿库溃坝致灾机制理论体系的形成，也对推进我国矿山固废的安全、绿色处置与矿山安全的发展具有重要的战略意义。

针对“尾矿库动/静力稳定性演化规律”和“溃决尾砂大变形运动-力学响应机理”重要科学问题，以堆存（铅锌）尾矿为研究对象，采用宏、细观实验与数值模拟结合的手段，厘清尾矿宏、微观特征参量的关系，完善了尾矿固结效应的综合判定准则；采用尾矿材料工程静、动力学特性以及分子动力学实验研究与数值模拟结合的手段，揭示了堆存尾矿静载作用下的细观结构和宏观力学行为演化规律及固结效应对尾矿库稳定性的影响机制，建立了堆存尾矿在三维应力状态下的流固耦合本构关系，并从颗粒排列的的微观角度分析粒度变化对尾矿物理力学性质的影响；研究了不同条件下永久位移变化量、塑性区的分布、加速度时程变化、地震液化等情况，揭示了多因素动载作用下堆存尾矿动力响应与耦合关系，并以此为依据，建立了尾矿库动/静力稳定性破坏机制及评价方法；采用物理模型与数值模拟结合的手段，研究了溃决尾砂流运动特征及对刚体的冲击效应，揭示了典型溃坝模式下尾砂运动-冲击效应时程规律，并基于未确知测度理论构建溃坝诱发泥砂流致灾区域危险度评价模型，综合判定溃决尾砂流对下游特征区域的危险度等级。这一研究有助于尾矿库溃坝致灾机制基础理论的体系化形成。