The goaf instability is one of the major safety risks during underground mining.In a setting of a copper zinc mine

the goaf was precisely detected using a void scanner（VS150）.By using the VoidScan-Geomagic-3D mine coupling technology

the fine reconstruction of the threedimensional goaf model for different time periods was realized

and the evolution of the mine goaf is analyzed.On this basis

a comprehensive goaf numerical simulation is conducted by using the coupled 3Dmine-Midas GTS NX-FLAC

3D

technology.According to the simulation results

the displacement field

stress field and plastic zone are analyzed

and the stability of the goaf roof and surrounding rocks is discussed.The evolution mec

hanism of the goaf in the future is also revealed.The results from numerical simulation are consistent with field measurement results

hence providing a scientific basis for the safety and timely treatment of goaf.