原地浸矿诱发离子型稀土矿山边坡变形机制及其稳定性研究

Study on slope deformation mechanisms and stability of ion‐adsorption rare‐earth mine induced by in‐situ leaching

为了揭示原地浸矿过程诱发边坡变形及失稳破坏机制,基于流固耦合理论,结合现场监测资料,对赣南某稀土矿原地浸矿过程的渗流场、变形场及边坡稳定性的演化规律进行了研究。结果表明:注液初期的渗流场影响范围主要分布在矿山顶部注液区内,导致山顶形成较大塑性区。随着注液强度不断提高,浸矿液浸润面快速抬升,矿山顶部塑性区向下沿着基岩朝两侧发展,诱发矿山边坡朝坡外向加速变形,导致边坡安全系数明显下降。当注液和收液强度大致平衡后,矿山内部形成稳定渗流场,边坡变形趋于稳定。总体来说,原地浸矿注液强度及浸润面高度是影响矿山边坡变形及稳定性的主要因素,相关研究成果为原地浸矿诱发滑坡的治理提供理论依据和工程参考。

In this paper,based on the fluid-solid coupling theory and combined with the field monitoring data,the evolution law of seepage field,deformation field and slope stability of a rare earth mine in southern Jiangxi Province during the in-situ leaching process are studied to disclose the mechanisms of slope deformation and unstable failure.The results show that the influence range of the seepage field in the initial phase of liquid injection is mainly distributed in the injection zone at the top of the mine,resulting in the formation of a large plastic zone on the top of the mountain.With the continuous improvement of liquid injection strength,the saturated surface of the leaching liquid rises rapidly and the plastic zone extends downward along the bedrock from the top of the mine to both sides of the slope,which induces the accelerated outward deformation of the mine slope and a significant decrease in the safety factor of the slope.When the injection and collection strengths are roughly in equilibrium,a stable seepage field is formed inside the mine,and the slope deformation tends to be stable.In general,the strength of in-situ leaching and the height of the saturated surface are the main factors affecting slope deformation and stability.The relevant research results provide a theoretical basis and engineering reference for the treatment of landslide induced by in-situ leaching.