某离子型稀土矿边坡稳定性分析及治理方案研究

发布时间：2018-05-28 21:40

本文选题：原地浸矿 + 离子型稀土矿　；参考：《江西理工大学》2015年硕士论文

【摘要】：原地浸矿施工条件下稀土矿边坡稳定性是一个时间域、空间域上的复杂的力学问题,虽然原地浸矿施工方法在离子型稀土矿开采中得到广泛的应用,但人们对原地浸矿如何影响稀土矿边坡稳定性的研究还很不足。本文依据某离子型稀土矿边坡实例,分析了原地浸矿条件下影响边坡稳定性的主要因素。在上述基础上,介绍了当前分析边坡稳定性的几种主流方法,并采用考虑地下水影响的条分法对稀土矿边坡进行了安全系数的计算;采用有限差分软件FLAC3D对不同浸矿时间下的稀土矿稳定性进行了数值模拟,得到了不同浸矿时间条件下稀土矿边坡应力场、位移场、应变增量场和渗流场等数据,分析了浸矿时间对边坡稳定性的影响;对植被护坡方案进行了模拟和分析,探讨了植被护坡方案对孔隙水压力、浅层安全性和深层安全性的影响,得到主要结论如下:(1)导致原地浸矿边坡滑动失稳的原因较多,主要包括浸矿溶液与表土的化学反应、稀土矿处于亚饱和状态下的降雨作用和稀土矿物理力学参数随注浆时间的变化等;(2)采用考虑了地下水影响的条分法对原地浸矿施工不同时间时边坡安全系数进行了计算,得到了不同时刻的边坡安全系数,结果表明前期安全系数减小不大,10天后安全系数降低到1以下,边坡处于不安全状态;(3)采用强度折减法对浸矿边坡进行了安全系数的求解,结果表明:未浸矿施工时,边坡安全系数为1.67;浸矿施工1、2、5、10和15天时,对应的安全系数分别为1.63、1.60、1.55、1.11和0.97;可以认为浸矿施工相当于一个缓慢的渗流作用,随着浸矿时间的增长,土体逐渐变成饱和状态,并且土体的物理力学参数也不断减小,使得边坡从稳定状态变成不稳定状态;(4)通过对植被防护方案分析可以确定:植被防护改变了稀土矿边坡孔隙水压力的分布情况,提高了边坡浅层的安全性,对深层安全性影响不显著。
[Abstract]:The slope stability of rare earth ore under in-situ leaching is a complex mechanical problem in time domain and space domain, although the construction method of in-situ leaching is widely used in ion rare earth mining. However, the study of how in situ leaching affects the slope stability of rare earth ore is still insufficient. Based on an example of an ion rare earth ore slope, the main factors affecting slope stability under in-situ leaching are analyzed in this paper. On the basis of the above, several main methods of slope stability analysis are introduced, and the safety factor of rare earth ore slope is calculated by using the strip method considering the influence of groundwater. The stability of rare earth ore under different leaching time is simulated by finite difference software FLAC3D. The stress field, displacement field, strain increment field and seepage field of rare earth ore slope under different leaching time are obtained. The influence of leaching time on slope stability is analyzed, and the effects of vegetation slope protection scheme on pore water pressure, shallow layer safety and deep layer safety are discussed. The main conclusions are as follows: (1) there are many reasons for the slippage instability of in-situ leaching slope, mainly including the chemical reaction between leaching solution and topsoil. The effect of rainfall on rare earth ore under the condition of sub-saturation and the variation of physical and mechanical parameters of rare earth ore with grouting time etc.) the slope safety factor under different time of in-situ leaching is calculated by using the strip method which takes into account the influence of groundwater. The safety factor of slope at different times is obtained. The results show that the safety factor of the slope is reduced to less than 1 after 10 days. The slope is in unsafe condition and the strength reduction method is used to solve the safety factor of the leachate slope. The results show that the safety factor of the slope is 1.67 when the ore is not leached, the safety factor of the slope is 1.63 ~ 1.601. 60 / 1. 55 / 1. 11 and 0. 97 respectively when the leaching is 1 ~ 2 ~ 2 ~ 5 ~ 5 ~ 5 ~ 10 and 15 days, respectively. It can be considered that the leaching construction is equivalent to a slow seepage effect, which increases with the leaching time. The soil gradually becomes saturated, and the physical and mechanical parameters of the soil decrease continuously. Through the analysis of vegetation protection scheme, it can be determined that vegetation protection has changed the distribution of pore water pressure of rare earth mine slope and improved the safety of slope shallow layer. The effect on deep safety is not significant.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD854.6

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