不同粒级与结构铁尾矿渗透破坏模式判别方法

渗透破坏是引起尾矿坝事故的重要原因。渗透破坏模式不同，影响也不尽相同。有必要对其判别方法进行研究，进而有效预判可能发生的尾矿坝渗透破坏形式，从而更为有效的保护尾矿坝下游人员的生命与财产安全。通过开展铁尾矿的渗透破坏试验，电镜扫描观测，显微镜观测，对细颗粒含量与结构影响下的铁尾矿渗透破坏模式进行了分析。结果表明：应用现行的一些渗透破坏模式判别方法对铁尾矿渗透破坏模式进行判别时，其准确性降低。以达西定律为基础，提出采用渗透系数对平均孔隙直径进行计算的方法，这种方法可以有效计算均匀尾矿的平均孔隙直径，沉积尾矿粗、细粒层的平均孔隙直径。为后续尾矿渗透破坏模式的判别提供有力依据。提出了适用于铁尾矿的渗透破坏模式判别方法。对不同粒级与结构铁尾矿的渗透破坏模式判别准确性较高。开展砂槽试验，在较大尺度范围上对提出的铁尾矿渗透破坏模式判别方法进行了验证，结果较为准确。研究成果对维持尾矿坝安全运行具有一定指导意义。

Research on Discrimination Method of Seepage Failure Mode of Iron Tailings with Different Grain Size and Structure

Seepage damage is an important reason of tailings dam accidents. Different modes of seepage damage have different effects. It is necessary to study the identification method, and then effectively predict the possible modes of tailings dam seepage damage. It can effectively protect the life and property safety of people downstream of the tailings dam. By conducting the seepage failure test of iron tailings and scanning electron microscope observation, the seepage failure mode of iron tailings under the influence of fine particle contents and structure was analyzed. The research shows that: 1) The accuracy some current methods for discriminating seepage failure modes is reduced. 2) Based on Darcy''s law, a method of calculating the average pore diameter by permeability coefficient is proposed. This method can effectively calculate the average pore diameter of uniform tailings and the average pore diameter of coarse and fine layers of sedimentary tailings. It provides a strong basis for the judgment of subsequent tailings seepage failure modes. 3) A method to discriminate the seepage failure mode suitable for iron tailings is proposed.The accuracy of discriminating the seepage failure mode of iron tailings with different fine particle contents and structures is higher. The sand tank test was conducted to verify the proposed method. The results are accurate. It has certain guiding significance to maintain the safe operation of tailings dam.