Goaf Stability, Reliability And Its Influencing Factors In The Sensitivity Analysis

At present, a large number of untreated mined-out areas have been left in majority mines of China. The mined-out areas influence safety production of mine very seriously. Therefore, the research of the mined-out area stability is very essential. The factors that affect mined-out area stability are many, for instance the exposition area of the roof, the column shape and the size the mine pillar, the physical mechanics nature of rock massif, the rock massif structural plane, the mined-out area tax save time condition, ground water, mining demolition vibration and so on. These factors are complicated and random. Its characteristic is, the actual situation often with difficulty in advance knew, or only to a certain extent may perform to estimate, but not accurate assurance. These uncertainty factors cause the major difficulty in worked-out section understanding. This article based on the dead weight stress field (had not considered that tectonic stress), the method introduction which the numerical simulation, the sensitivity and reliability analysis unifies to the worked-out section investigation into stability work, through the research, has made some meaningful progresses.The first, unify the orthogonal design and the numerical simulation, based on the multi-factors, multi objective's sensitive analysis thought that through the generalized analysis comparison, will affect the worked-out section stable various factors to carry on sorting, finally determined that the adjacent formation the physical mechanics parameter, the worked-out section highly, the roof exposition area and worked-out section burying depth these factors when carries on reliability analysis should give the key consideration.The second, according to the Mole theory of strength, the union numerical simulation analysis's result, the use multi-dimensional linear regression, has obtained the worked-out section stable limiting condition equation, based on the Monte-Carlo and the JC, has established reliability computational procedure. Two methods computation reliability result is consistent.The third, through to reliability sensitive analysis, obtains the burying depth and the adjacent formation mechanics parameter affects the worked-out section stable important attribute, next is the worked-out section shape.The fourth, in the actual project, speaking of a concrete mine, the burying depth and the adjacent formation mechanics parameter are relatively fixed, what but may control the worked-out section shape, according to the burying depth and the adjacent formation mechanics parameter determined that the stope design parameter, is the guarantee safe highly effective mining key, also guarantees a worked-out section stable essential measure.