Analysis On Tendency Of Rock Burst And Stability Of Surrounding Rock Of Roadway In Depth Mine Of Jinchuan

Nickle ore of Jinchuan is well known to the world for its deep buried depth, high grostatic stress, crumble rock mass and ill-conditioned for exploiting. With the increase of mining depth of Jinchuan No.2 Mining District recent year, which is the brunt of Jinchuan Nickle ore, several technical problmes occur and become the urgent concern of engineers, such as degradation of surrounding rock,rock burst, water-rock interaction inducing stability of tunnel and so on. The types of tunnel supporting and surrounding rock control using in shallow mining are no longer suit for deep mining. So it is necessary to do full research into deep mining area in order to derive main factors which affect stability of of surrounding rock, accordingly, relevant analysis methods and controlling technique for complicated condition are proposed.This paper probes into tendency of rock burst in Jinchuan No.2 Mining distrist and study seepage effect exerts impact on stability of surrounding rock, which bases on project of'Research on Rock Mechanics Under Condition of Deep and Hi-impact Mining in Jinchuan ore'and combines situ monitoring, engineering geology survey and numerical analysis. Main efforts of this paper are as follows:1. Situ survey have been conducted in Jinchuan No.2 district. Rock samples conllecting and previous research data analyzing provide informatin of geological structure and characteristics of weak plane of rock.2. Normal rock mechanics experiments have been conducted so as to study tendency of rock burst. Based on results of experiments and compared to previous research, fuzzy mathematics has been chosen as a tool to study tendency of rock burst in deep mining, which may induce by several factors. Study results show that rock burst criteria which considers only one fator are not suit for deep mining in Jinchuan. So this paper advises that the results would be more acceptable by using comprehensive study method which considers overall factors' co-ativation. Based on the advised method, this paper derives weak rock burst tendency of six typical type of rock specimens collected in deep mining district.3. Another endeavor of this paper is to study seepage effect exert impact on stability of surrounding rock in deep mining. Computing model of equivalent continuum under coupling condition has been set up by using finite element method software MIDAS/GTS. Then numerical analysis of the model has been conducted by comparing condition that seepage exert on surrounding rock and that of it is not. Results reveal that stress redistribution induced by tunnel excavation have evident effect on distribution of seepage field, and change of seepage field have feeble impact on deformation and stress distribution of surrouding rock.