Research On Instability Response And Control Technology Of Goaf Group Based On The Frame Structure Method

With the majority of metal mines into underground mining,the number of goaf is also increasing,even in some areas,even in some areas,there has been a gathering of mined areas,forming a group goaf.Due to the technical and economic factors at that time,the goaf group has not been effectively managed.However,in the event of the failure of the goaf group,there will be a disaster such as shock wave and surface collapse,which is a serious threat to the underground personnel and equipment safety.Therefore,it is of great significance to carry out the research on the instability response and control of the goaf group instability.In this paper,the underground goaf group of a large-scale gold mine is taken as the research objective.With the help of the theory and method of frame structure,the failure response of goaf group is carried out by field survey,theoretical analysis,numerical simulation and field engineering verification related research,a corresponding control method is proposed for the “short slab” unit gob.The main work of the paper is as follows:(1)The theory and method of frame structure are summarized,including the static analysis method and dynamic analysis method of frame structure.Combined with the distribution of underground goaf group of a large-scale metal mine,the theoretical method applicable to the metal mine is determined.(2)The method of similar layer shearing model for dynamic response of goaf group was presented.The overburden rock was equivalent to a system composed of the “virtual inter column group” and the lumped mass block,The surrounding rock was equivalent to shear force.The similar layer shearing model of goaf group and the corresponding dynamic differential equations was established to study the displacement and velocity response of rock mass media in the goaf group,and evaluate the overall stability of the goaf group.(3)Constructing the model of self-stabilization of goaf-group frame structure,the typical displacement equations of the internal structure of goaf group are established.The calculation formulas of the stability coefficients of the top and the column are given based on the theory of rock strength,and the important factors and of top and column are introduced.to identify the “short slab” unit gob.and the self-stabilization coefficient method of the frame structure provides a new and effective way for the screening of “short slab” unit gob of goaf group.(4)Based on the identification of the “short slab” unit gob in the goaf group,the blank area of the "short board" unit is filled and processed by FLAC3 D numerical simulation method and the method of similar layer shearing model.The stability of the goaf group is analyzed,and the theoretical support and relevant guidance for the instability control of the goaf group are evaluated.The stress field,displacement field,velocity field response characteristics and distribution law of the population are evaluated.The overall stability of the mined-out group after the filling process is evaluated,which provides theoretical support and related guidance for the instability control of the goaf.