露天矿排土场主要面临着滑坡和泥石流的严重威胁，排土场稳定性问题不仅是一个安全问题也是一个经济问题。堆载和降雨是影响排土场稳定性最重要的2个因素，但目前精准、高效的排土场滑坡监测预警一直是一大难题，亟待开展相关方面的研究。针对以上问题，以辽宁本溪南芬露天铁矿Ⅱ号全段高排土场为研究对象，以监测光纤组成监控网对Ⅱ号全段高排土场的相似物理模型开展堆载及降雨模拟实验。结合不同堆载条件下排土场变形的数值模拟和降雨影响下模型材料的电镜扫描结果，以物理、数值模拟及宏观、微观多重手段相交叉融合的方式进行不同堆载和不同降雨条件下排土场不同位置的变形分析，得出排土场变形与堆载增量呈正相关，但深度的增加使边坡变形敏感度降低;与单位降雨时长呈正相关，但随着降雨总时长推移排土场发生排水固结，变形量减小使得二者呈负相关的时空演化规律。数值模拟计算结果显示堆载作用下排土场边坡形成贯通滑动面的过程;微观分析结果表明排土场边坡在降雨影响下泥质胶结材料冲刷流失，颗粒间接触力减小，排弃物间隙变大形成潜在滑动面。堆载增加使降雨在边坡内部产生的潜在滑动面扩大最终形成贯通的滑动面。结合物理模型实验结果对滑动面进行精准定位，最后依据室内物理模型实验和数值分析结果，建议使用光纤传感技术作为排土场边坡变形失稳的监测手段

Open pit dumps mainly face the serious threats of landslides and mudslides.The stability problem of dumps is not only a safety issue but also an economic issue.Heap loading and rainfall are the two most important factors affecting the stability of dumping site.However,the accurate and efficient monitoring and early warning of dumping in the dumping site have always been a major problem,and it is urgent to carry out research on some related aspects.In view of the above problems,the No.2 full section high dump at Nanfen open pit iron mine was taken as the research object,and a monitoring network composed of monitoring optical fibers was used to carry out some heap loading and rainfall simulation experiments on the similar physical models of No.2 full section high dump.Based on the numerical simulation of the dump deformation under different loading conditions and the scanning results of the model materials under the influence of rainfall,the deformation analysis of different positions of the dump under different loading conditions and different rainfall conditions was carried out by means of physical,numerical simulation and cross integration of macro and micro multiple means,and finally the temporal and spatial evolution laws of the dump deformation under different loading and rainfall conditions were obtained.It is concluded that the dump deformation is positively correlated with the increment of loading,but the slope deformation sensitivity decreases with the increase of depth.It is positively correlated with the unit rainfall duration,but with the total rainfall duration,drainage consolidation occurs in the dump,and the deformation decreases,making the two negatively correlated.The numerical simulation results show the process of forming a through sliding surface of the dump slope under the action of heaps.The microscopic analysis results show the formation mechanism of the potential sliding surface of the dump slope under the influence of rainfall.The sliding surface is precisely positioned according to the experimental results of physical model.Finally,based on the results of laboratory physical model experiments and numerical analysis,it is suggested to use optical fiber sensing technology as a monitoring method for slope deformation and instability in the dumping site

1 排土场区域地质及稳定性概况

2 排土场边坡相似物理模型

　　2.1 排土场边坡相似模型设计

　　2.2 排土场边坡相似模型变形监测设备

　　2.3 排土场边坡相似模型实验设置

3 排土场边坡模型实验结果分析

　　3.1 不同堆载条件下模型应变分析

　　3.2 不同降雨条件下模型应变分析

　　3.3 滑动面位置判断

4 排土场边坡堆载变形数值模拟分析

　　4.1 数值模型的建立

　　4.2 堆载变形数值模拟结果分析

5 工程尺度排土场边坡稳定性监测方法设计

6 结论