Abstract: The stability evaluation of underground complex goaf group and its dynamic disaster prevention and control are the common problems faced by the safe mining of deep mineral resources.Aiming at the technical problem that it is difficult to accurately identify the instability risk of large-scale and irregular goaf group system,a collaborative evaluation scheme combi ning improved Mathews stability diagram method and FLAC3D numerical simulation is proposed.Firstly,based on the fine field investigation and rock mechanics parameters,the improved Mathews stability diagram method is used to classify the initial sta bility of the goaf.A three-dimensional numerical model reflecting the spatial correlation characteristics of goaf group is con structed to simulate and analyze the evolution law of stress-displacement field and the expansion and connection mechanism of plastic zone under the influence of mining.Through the mutual verification of the two methods,the spatial aggregation and non linear evolution characteristics of the cavity group instability are revealed,and the high-risk area of instability is delineated.Fi nally,based on the theory of impact wave dynamics,a coordinated disaster prevention and control scheme of "buffer layer ener gy dissipation + wave barrier isolation" is proposed,and the theoretical calculation model of key parameters is given.Taking the complex goaf group of III-IV ore body in Dahongshan Iron Mine as the engineering background,17 goaf areas are delineated as high risk areas of instability by using the proposed technical method,and the disaster prevention and control scheme of re serving waste rock cushion + building concrete wave wall is formulated.The technical system of "precise risk identification deep mechanism analysis-hierarchical targeted prevention and control" formed by this study provides a universal theoretical ba sis and technical path for the treatment of complex goaf groups in similar mines,and has important reference value for ensuring  thesafeminingofdeepresources.

Key words: complexgoaf group,Mathews stabilitygraph,numerical simulation,stabilityevaluation,shockwave,disaster prevention