富水冰碛层竖井施工过程数值模拟  

Numerical Simulation Study on Shaft Construction Process of Water-rich Moraine Layer

作　　者：过江[1] 蒋倪明 程鑫 GUO Jiang;JIANG Niming;CHENG Xin(School of Resources and Safety Engineering,Central South University,Changsha 410083,Hunan,China)

机构地区：[1]中南大学资源与安全工程学院,湖南长沙410083

出　　处：《黄金科学技术》2022年第5期733-742,共10页Gold Science and Technology

基　　金：湖南省研究生科研创新项目“富水破碎土层井筒综合加固技术研究与实践”(编号:QL20210054)资助。

摘　　要：针对冰碛层围岩固结程度低、围岩力学性质差且内部含冰水积层等特点,分析冰碛层土体条件下竖井施工过程中围岩变形情况,研究施工过程中支护结构受力特性,优化冰碛层土体条件下竖井施工方案。以四川凉山小麻柳尾矿库8#竖井工程为例,结合实际工程情况,利用FLAC^(3D)软件对不同竖井施工方案的施工过程进行数值模拟,得到了竖井施工侧壁围岩随施工过程的变化规律及特征。由数值计算结果和实际施工情况可知,反井导洞扩挖法在冰碛层等弱固结、富水土层的施工效果较好,渗流场孔隙水压力及竖井侧壁围岩应力较小,对周边围岩的扰动较小,能够有效降低土体变形。As an important part of mine construction,shaft engineering is also a key project to ensure the normal operation of the mine.With the continuous development and utilization of resources,the difficulty of resource extraction also increases,and more and more shaft projects need to be constructed under complex geological conditions.Moraine layer is a special geotechnical material widely distributed in the western region of China,there is more and more construction projects on this type of soil.Compared with the general surrounding rock structure,the soil mass of the moraine layer is basically composed of debris,the surrounding rock is mostly in a soft plastic state,the degree of consolidation is low,and the stability of the soil body is poor.The pressure is high,and the general shaft construction method is difficult to apply to the construction of this type of soil.Therefore,in order to improve the construction efficiency of the shaft under the geological conditions of the moraine layer,control the deformation of the surrounding rock during the construction of the shaft under the soil condition of the moraine layer,and optimize the construction plan of the shaft under the soil condition of the moraine layer.Taking the 8#shaft project of Xiaomaliu tailings pond in Sichuan as an example,using the research method of numerical analysis,combined with the actual engineering situation,considering the influence of underground diving in the moraine layer soil on the construction operation of the shaft,the shaft construction process of the vertical shafts by forward excavation method,full-section reverse shaft method and reverse shaft pilot tunnel expansion method were analyzed,and the distribution of pore water pressure,stress,displacement and plastic zone after the construction of the three types of shafts were analyzed.It can be seen from the simulation results that the construction effect of the excavation method is better,followed by the forward excavation method,and the construction effect of the full-section reverse me

关 键 词：竖井施工 冰碛层 流固分析 应力分布 位移变化 塑性区 

分 类 号：TU42[建筑科学—岩土工程]