Comprehensive Evaluation of Goaf Stability in Daye Lingbao Iron Mine
|School||Wuhan University of Science and Technology|
|Keywords||Stability Analysis Rock Mass Rating System Q System 3D FEM Acoustic Emission Monitoring|
In the course of mining, the stress in arounding rock mass will redistribute, when this kind of stress exceeds surrounding rock’s ultimate strength, surrounding rock will lose its stability and destruct. Consequently, it becomes increasingly important for the study of the forced condition of rock mass and its stability during mining.Associated with Daye Lingbao iron mine in this paper, sticking to the evaluation of rock’s stability, aiming to providing bases for mining residual ore in this mine, with the combination of qualitative evaluation, quantitative evaluation, the rock’s stability of goaf is studied systematically. Finding out the engineering geological and hydrogeololgy factors influencing rock’s stability of goaf by resourcing and field survey. Classifying the rock mass using RMR method and Q system method, according to the results of point load index test for rock selecting in the depth -88m, and the specific geological conditions of Lingbao iron mine. The quality of rock mass in this mine is good. Building 3D model of Lingbao iron mine by ANSYS, evaluating the effect on the stability of the rock mass during residual ore mining, through analyzing the distributing law of stress and safety factor in rock mass before and after residual ore mining. Through to the condition investigation of underground goaf, the suggestion on the method of dealing with goaf is closed, including goafs above -70m level and below -88m level in Xiaobaoshan mine. Finally, arranging acoustic emission monitoring points reasonably in the stress concentration area of goaf, monitoring pressure activities of rock mass in the main goaf, analyzing the data, predicting the change trend of rock’s stability, and providing directive significance for the safety of mining residual ore.