降雨对矿山碎石土堆积体边坡稳定性影响  

Effect of rainfall on slope stability of mine gravel soil piles

作　　者：杨宗耀 任东兴 王豪 赵海堂 吴鑫 YANG Zongyao;REN Dongxing;WANG Hao;ZHAO Haitang;WU Xin(Chengdu Surveying Geotechnical Research Institute Co.,Ltd.of MCC,Chengdu 610023,China;Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China;College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China;Chengdu Engineering Corporation Limited,Power Construction Corporation of China,Chengdu 611130,China)

机构地区：[1]中冶成都勘察研究总院有限公司,成都610023 [2]西南交通大学地球科学与环境工程学院,成都611756 [3]成都理工大学环境与土木工程学院,成都610059 [4]中国电建集团成都勘测设计研究院有限公司,成都611130

出　　处：《有色金属（矿山部分）》2023年第2期112-117,共6页NONFERROUS METALS(Mining Section）

基　　金：国家自然科学基金项目(42072313);四川省科技计划项目(23NSFSC3010)联合资助

摘　　要：降雨形成的坡面流和渗流对排土场边坡的稳定性会产生一定影响。利用数值模拟技术,对西藏某铁矿排土场碎石土堆积体进行流固耦合计算,研究7天连续降雨对碎石土边坡的稳定性影响,得到以下结论:1)基于气象记录的最大降雨强度138 mm/d,在连续7天的降雨条件下,未对碎石土边坡造成明显的稳定性影响,安全系数从降雨前1.73降低至第4天的1.65后保持不变,最终安全系数远大于规范要求;2)饱和区首先在碎石土堆积体坡顶后缘和坡脚位置形成,随后基岩坡表局部也形成饱和区,在第4天表层的饱和区连通,湿润峰和饱和区随即逐渐向下扩散移动。表明前期渗流以沿坡表向下方向为主,后期以竖直向下为主;3)对碎石土堆积体各个部位的监测表明,此层中从未形成暂态饱和区,坡脚区域的饱和度大于坡顶后缘区域,两处均大于坡体其它区域。The slope surface flow and seepage formed by rainfall will have a certain influence on the stability of the slope of the soil discharge site.In this paper,we use numerical simulation to carry out flow-solid coupling calculation on the gravel soil pile of a Tibetan iron ore mine drainage field to study the stability influence of seven days of continuous rainfall on the gravel soil slope,and get the following conclusions:1)The maximum rainfall intensity of 138 mm/d based on meteorological records did not cause significant stability effects on the gravel soil slope under the rainfall conditions for seven consecutive days,and the safety factor was reduced from 1.73 before the rainfall to 1.65 on the fourth day and then remained unchanged,and the final safety factor was much higher than the specification requirements;2)The saturated zone was first formed at the back edge of the top of the gravel soil accumulation and the location of the foot of the slope,and then the saturated zone was also formed locally at the bedrock slope surface,and the saturated zone at the surface layer was connected on the fourth day,and the wetting front and the saturated zone then gradually spread and moved downward.It shows that the seepage is mainly in the downward direction along the slope surface in the early stage and the vertically downward direction in the later stage;3)The monitoring of various parts of the gravel soil accumulation body shows that the transient saturation zone has never been formed in this layer,and the saturation degree in the region of the foot of the slope is greater than that in the region of the back edge of the slope top,and both of them are greater than the other regions of the slope body.

关 键 词：降雨入渗 碎石土 边坡稳定性 饱和渗流 安全系数 

分 类 号：TD854.7[矿业工程—金属矿开采]