摘要
为研究某露天矿内排土场出现裂缝及底鼓的原因,分析持续降雨条件下内排土场边坡变形破坏机理、稳态渗流孔隙水压力变化与瞬态渗流坡体内部孔隙水压力变化规律,查明边坡变形破坏力学特性及持续降雨条件下坡体位移规律;利用现场调研成果与渗流基本理论,通过Geostudio软件对内排土场坡体的孔隙水压力变化规律进行了全过程模拟,利用有限元模拟方法,对持续降雨下边坡位移情况进行分析,得到了其变形规律及塑性变形情况。结果表明:随着降雨的不断持续,地下水位不断升上,靠近地表出的孔隙水压力以圆弧形扩散排列,中部的孔隙水压力值最大,相对应的边坡内部静水压力作用减小,动水压力作用效果增强;降雨强度的不断提升,影响到基底上部泥岩层的抗剪强度,尤其对内摩擦角影响最为敏感,导致边坡的稳定性继续降低;坡体x方向位移、y方向位移及总位移随着降雨的不断持续,逐渐增加,即与降雨时长成正相关,第7 d总位移可达到7.12 mm,泥岩为主要滑动层。
In order to study the causes of cracks and floor heave in the internal dump of the open-pit mine,the article analyzes the deformation and failure mechanism of the internal dump slope under the condition of continuous rainfall,the variation law of the steady-state seepage pore water pressure and the transient seepage pore water pressure inside the slope body,and finds out the mechanical characteristics of slope deformation and failure and the displacement law of the slope body under the condition of continuous rainfall.Based on the field investigation results and the basic theory of seepage,we simulate the variation law of pore water pressure on the slope of the internal waste dump in the whole process through Geostudio software.The article analyzes displacement of the slope under continuous rainfall using the finite element simulation method,and obtains its deformation law and plastic deformation.The results show that with the continuous rainfall,the groundwater level keeps rising,the pore water pressure near the surface is arranged in circular diffusion,the pore water pressure value in the middle is the largest,the effect of the corresponding internal hydrostatic pressure of the slope is reduced,the effect of the hydrodynamic pressure is enhanced,and the rainfall intensity keeps rising,which affects the shear strength of the mudstone layer at the upper part of the basement,especially the influence of the internal friction angle,The stability of the slope continues to decrease.The displacement in x direction,ydirection and total displacement of the slope increase gradually with the continuous rainfall,that is,they are positively correlated with the rainfall duration.The total displacement can reach 7.12 mm on the 7th day,and mudstone is the main sliding layer.
作者
缪海宾
马明康
MIAO Haibin;MA Mingkang(China Coal Technology and Engineering Group Shenyang Research Institute Co.,Ltd.,Fushun 113122,China;State Key Laboratory of Coal Mine Safety Technology,Fushun 113122,China)
出处
《露天采矿技术》
CAS
2023年第2期5-7,12,共4页
Opencast Mining Technology
基金
国家重点研发计划资助项目(2021YFC3001901)。
关键词
渗流作用
边坡变形破坏
关键层
数值模拟
孔隙水压力
seepage action
slope deformation and failure
key layer
numerical simulation
pore water pressure
