Study On Cooperating Effect Of Risk Factors In Metal Underground Mine

Owing to the increasing demand for resource with the national economy developing, the proportion of underground mining increases day by day. The security problem, which is payed comprehensive attention, become more and more prominent. In recent years, many scholarshave sdudied on it systematically by the methods of the rock mechanical theory, apparatus monitoring and numerical calculating, and achieved remarkable effects. However, the analyses deeply indicated that, the security problems that the collasping and rock-falling occuring in underground stope is caused by the combined acting of rock strenth, the condition of faults and weak planes, hydrographic status and theadjacent rock stress. If the single method only being used, the result would be biased.The article is based on the project "The study on efficient mining and safety" in copper-iron ore in Tonglu mount, it post the dominant facts affecting stope security and constructed the cooperating effect model for evaluating the stope danger degree. According to the three dominant facts affecting stope security, it has been studied from three aspects. First, Through the geological investigation on stope 7313 in Tonglu mount, this article classified the rock quality with the method of RMR, and found the distributing rule of rock quality; It established the finite element model of Stope 7313 using 3-dimension FEM numerical soft ANSYS 8. 1 based on field testing and indoor calculating, then gained the rock stress distributing rule after analyzing the stress situation in the stope; through account testing on surrounding rock in stope 7313, it studied the effecting range of blasting and took the damage rule of surrounding rock with numerical regress method. Taking the jobs above as foundation, this article determined each weight of danger factors in Stope 7313 by the method of AHP, and discrete the two key sections by the method of meshing, then put all of the attribute values of mesh points into software surfer 8. 0, to have drawn the factor effecting distributing map of the section located in stope center and stope roof. And in the meantime, in order to find the composite danger degree, three types of cooperating effect model were adopted. Compared and studied, finally the model of "Weight-Index" has been selected as the best one and used to estimate the danger degree for each key position in the stope.