The Stability Analysis And Safety Forecast Of The Goaf In Mental Mine

The stope method was adopted in many mental mines in our country , and left a lot of mined-areas. The exist of the mined-areas will be able to cause many harms,such as rock burst,surface collapse,environment destroy and so on. Therefore,it's necessary to analyze the stability of the mined-areas,and provide theoretical basis for the safety production and resource recycling.This paper has analyzed on the roof caving in Jinling iron mine. In order to analyze the stability of the mined areas, FLAC^3D has been used. This paper contains:1 .Building complex 3D modelBuilding mechanical model of the surrounding rocks before the roof caving. Using the powerful modeling and meshing function of ANSYS, this paper has built 3D model of whole complex mined areas in ANSYS and created the files of the nodes and elements .Through the data conversion program, the model can be conversed to build in FLAC^3D.2.Analyzing the stress and displacementThe progress of minings has been simulated statically by using FLAC^3D, and the stress and displacement law are analyzed during mining .The roof of the mined areas is in the state of tensile,and becomes smaller during the mining;the surrounding of the mined areas moves to the mined areas and becomes larger. It can be concluded that the 403 pillar was the beginning of the destroy.3.Calculating the safety factorConducting strength reduction by using "SOLVE fos"in FLAC^3D to analyze the shear strain increment, the block state and calculate the safety factor after the mining. The safety factor is larger ,because the influence of the faultage, joints etc. have not been taken into consideration when simulating. But it is more able to destroy at the 403 pillar,the roof of the 601 mined area and the 405 mined area march with 602 mined area ,and it's consistent with the real condition.Compared with the method of lasting observation , the method of numerical simulation can make quick and rational evaluation when analyzing the stability of the roof in mined areas. And this can provide foundation on the forecast and prediction of the stability in mined areas.