富水砂卵石地层露天矿止水固坡技术研究及应用  

Research and application of technology of water cutoff and slope reinforcement in open-pit mines in sandy gravel aquifer

作　　者：韩龙强 吴顺川 高永涛[2] 王广和[3] 王慧珍 刘洋 严琼[4] 张化进 HAN Longqiang;WU Shunchuan;GAO Yongtao;WANG Guanghe;WANG Huizhen;LIU Yang;YAN Qiong;ZHANG Huajin(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming,Yunnan 650093,China;Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines,University of Science and Technology Beijing,Beijing 100083,China;Zhongkan Metallurgical Geotechnical Investigation Design and Research Institute Co.,Ltd.,Baoding,Baoding,Hebei 071069,China;Powerchina Roadbridge Group Co.,Ltd.,Beijing 100048,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]北京科技大学金属矿山高效开采与安全教育部重点实验室,北京100083 [3]中勘冶金勘察设计研究院有限责任公司,河北保定071069 [4]中电建路桥集团有限公司,北京100048

出　　处：《岩石力学与工程学报》2022年第12期2460-2472,共13页Chinese Journal of Rock Mechanics and Engineering

基　　金：云南省高层次人才引进计划“高层次创新创业团队”;云南省高校科技创新团队支持计划资助。

摘　　要：为解决腾龙铁矿富水砂卵石地层的止水固坡技术难题,针对边坡高水压–低强度的复杂条件,首次将大型地下连续墙技术引入露天矿治水领域,沿矿坑南帮39 m平台布设一道总长度1152 m、最大深度50 m的弧线型地下连续墙止水帷幕。通过数值实验分析地下连续墙结构参数:混凝土强度等级、墙体厚度、墙底嵌入基岩深度和布设位置对墙体侧向位移、应力状态和弯矩的影响规律,发现墙体弯矩对参数变化的敏感性更强,建立“抗弯安全度”试验指标,设计正交试验对地下连续墙结构参数进行优化,提出地下连续墙的最优参数组合:混凝土强度等级C25,墙体厚度800 mm,嵌入基岩深度2~3 m,布设位置距离平台外边缘10 m。通过计算与现场监测结果可知,施作地下连续墙后矿坑日涌水量减少约97%,墙体抗弯强度和抗剪强度均满足规范要求,各剖面边坡稳定性显著提高,地下连续墙兼具挡土和止水的双重作用。研究成果解决了富水砂卵石地层中开挖露天矿边坡的重大技术难题,可为类似矿山的防渗工程提供有益参考。To solve the technical problem of water cutoff and slope reinforcement in water-rich sandy gravel aquifer in the Tenglong iron mine,aiming at the complex conditions of the slope with high water pressure and low strength,the technology of large-scale underground diaphragm wall was first introduced into the water-management field in an open-pit mine.An arc-shaped underground diaphragm wall preventing water curtain with a length of nearly 1152 m and a maximum depth of 50 m was built along the 39 m platform on the south side of the pit.The influence laws of structural parameters of the underground diaphragm wall such as the concrete strength grade,the thickness and location of the wall,and the depth of wall embedded into the bedrock,on the lateral displacement,stress state and bending moment of diaphragm wall were analyzed by numerical experiment,and it was found that the bending moment was more sensitive to the variation of parameters.The test index“anti-bending safety”was proposed and the orthogonal experiment was designed to optimize the structural parameters of the underground diaphragm wall.The combination of optimal parameters was proposed,with the concrete strength grade of C25,the thickness of the wall of 800 mm,the depth of the wall embedded into bedrock of 2–3 m and the location of 10 m away from the outer edge of the platform.According to the numerical calculation and field monitoring results,after constructing the underground diaphragm wall,the anti-bending strength and anti-shear strength of the diaphragm wall can satisfy the specification requirements.The drainage volume of the mine has been reduced by 97%,the slope stability has been significantly improved.The diaphragm wall has the double functions of soil retaining and water cutoff.The research results have successfully solved the major technical problems of slope excavation in the open-pit mine in water-rich sandy cobble ground,and it can provide a useful reference for anti-seepage engineering in similar open-pit mines.

关 键 词：采矿工程 露天矿 富水砂卵石层 地下连续墙 止水固坡 

分 类 号：TD32[矿业工程—矿井建设]