崩落法转充填法开采安全隔离层厚度研究  

Study on thickness of safety isolation layer in caving-to-backfilling mining

作　　者：何环莎 王旭 刘畅 赵亮 吕冠颖 吴翔伟 HE Huansha;WANG Xu;LIU Chang;ZHAO Liang;LYU Guanying;WU Xiangwei(Changsha Institute of Mining Research Co.,Ltd.,Changsha 410012,China;National Key Laboratory of Metal Mine Safety Technology,Changsha 410012,China;Hunan Engineering Technology Research Center of Mine Geological Hazard Control and Environmental Reconstruction,Changsha 410012,China)

机构地区：[1]长沙矿山研究院有限责任公司,湖南长沙410012 [2]金属矿山安全技术国家重点实验室,湖南长沙410012 [3]湖南省矿山地质灾害防治与环境再造工程技术研究中心,湖南长沙410012

出　　处：《中国矿业》2024年第8期176-183,共8页China Mining Magazine

摘　　要：地下矿山崩落法转充填法开采是矿山行业维持可持续发展与保护生态环境的重要趋势,为保障某大型地下矿山崩落法转充填法安全开采的有序衔接,本文对该矿安全隔离层厚度及稳定性进行了深入的计算与分析。首先,通过荷载传递线交汇法、结构力学简化梁法、普氏拱理论计算了隔离层厚度,厚度分别为19.5 m、20.1 m和22.7 m;其次,建立三维精细化矿体开采模型,设计崩落法转充填法安全隔离层15 m、20 m、25 m三种厚度方案进行对比,采用有限差分计算软件FLAC^(3D)对矿体崩落法分层开采、充填法首采中段开挖进行了全过程模拟。研究结果表明:安全隔离层厚度20 m时,最大沉降变形值为21 cm,最小主应力为压应力0.05 MPa,隔离层岩体未出现受拉破坏,产生的塑性破坏区域零散分布,影响范围有限。综合理论计算和数值模拟结果,最终确定矿山安全隔离层厚度应不小于20 m。矿体留设安全隔离层可有效降低崩落法开采和充填法开采区域的相互影响,保证深部矿体充填法开采的安全进行,研究方法和结果可为相似条件矿山提供参考。Caving-to-backfilling mining in underground mines is an important trend to maintain sustainable development and protect the ecological environment in the mining industry.In order to ensure the orderly connection of safe mining from caving method to back filling method in a large underground mine,the thickness and stability of the safety isolation layer of the mine are calculated and analyzed in depth.Firstly,the thickness of the isolation layer is calculated by means of the intersection method of load transfer lines,the stress condition of the beam and plate,and the platts theory,the thicknesses are 19.5 m,20.1 m and 22.7 m;secondly,a three-dimensional refined ore body mining model is established,and three thickness schemes of 15 m,20 m and 25 m of safety isolation layer in caving-to-backfilling mining are designed and compared.The finite difference calculation software FLAC^(3D) is used to simulate the whole process of stratified mining by caving method and the excavation of the first mining middle section by back filling method.The results show that when the thickness of the safety isolation layer is 20 m,the maximum subsidence displacement value is 21 cm,the minimum principal stress is 0.05 MPa,there is no tensile failure in the rock mass of the isolation layer,and the plastic failure area is scattered and the influence range is limited.Combining theoretical calculations and numerical simulation results,it is finally determined that the thickness of the mine safety isolation layer should not be less than 20 m.Leaving a safety isolation layer in the ore body can effectively reduce the mutual influence of the caving mining and back filling mining area,and ensure the safety of the deep ore body back filling mining,and the research method and results can provide a reference for the mines with similar conditions.

关 键 词：崩落法转充填法 安全隔离层厚度 数值模拟 岩层移动 稳定性分析 

分 类 号：TD861[矿业工程—金属矿开采]