固体钾盐矿山房柱式开采地表沉陷的理论计算

Theoretical calculation of surface subsidence in room and pillar mining of solid potash mine

条带房柱式开采法是世界固体钾盐矿山最主要的采矿方法,光卤石/钾石盐是最主要的含钾开采矿石,具有可溶于水、易吸水潮解、内聚力大等独特的物理力学特性,导致不能完全照搬随机介质理论用于地表沉陷的计算。因此,以老挝某固体钾盐矿山作为工程背景,基于弹性半无限空间理论,建立条带房柱式开采的力学模型,利用弹性力学线性荷载的布辛内斯克解,理论计算地表沉陷量,并进一步利用FLAC 3D数值模拟软件建立地表沉陷力学模型,数值仿真计算地表变形量。结果表明,在矿房宽度为8 m,矿柱宽度为10 m的情况下,采用理论和数值模拟软件计算,地表下沉系数q均在0.05左右,与国内外房柱式开采的工程经验基本一致。

Strip room and pillar mining method is the most important mining method for solid potash mines in the world.Carnallite/sylvine is the most important mining ore.It is soluble in water,easy to absorb water and deliquesce,and has great cohesion.The distinctions of physical and mechanical characteristics make it impossible to completely copy the random medium theory for the calculation of surface subsidence.Therefore,taking a solid potash mine in Laos as the engineering background,based on the theory of elastic semi-infinite space,a mechanical model of strip room and pillar mining is established,and the Bucinnesk solution of the linear load of elastic mechanics is used to theoretically calculate the amount of ground subsidence,and further more.The FLAC^(3D) numerical simulation software is used to establish the surface subsidence mechanical model,and used to calculate the surface deformation.The conclusion show that the width of the mining room is 8 m and the width of the pillar is 10 m,the theoretical calculation and numerical simulation software are used to calculate,and the surface subsidence coefficient q is about 0.05,which is consistent with the engineering experience of room and pillar mining at home and abroad.