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

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.