DEFORMATION,FAILURE AND ANALYSIS OF CONVERGENCE MONITORING OF ROCK MASS IN DEEP HIGH-STRESS AND SWELLING ROADWAY

Jinchuan Mine is the largest nickel-cobalt resource base in China. The deep rock mass in the mining area is characterized by crushing, creeping and expansion. The stability of roadway rock mass is the key issue of the sustainable development for the mining area. In this paper, the engineering geological investigation of the deformation and failure of deep rock mass, and the analysis of monitoring results of the deep experimental roadway convergence deformation are carried out. The results show that:(1) As the roadway rock body develops to the deep, the mining area expands and the ground pressure activity increases. Small fractures and other weak structural planes develop. The constrained deformation of the rock mass under the influence of the disturbing stress field is intensified, and there may be serious yield deformation and overall instability in the roadway. (2) Comprehensive site engineering geological survey and analysis of deformation and failure mechanism of roadway surrounding rock, complicated surrounding rock engineering geological conditions, aging characteristics, mining impact, high stress, crack shear creep, crack filling water-rock reaction and other unfavorable factors make the surrounding rock in the deep roadway exhibit obvious characteristics of creep and overall necking. (3) The analysis of monitoring data of roadway rock mass converging deformation shows that the deformation of broken rock mass in deep roadway is the overall deformation of the surrounding rock and the necking occurs. Convergence and deformation of roadway rock mass are mainly affected by high ground stress and rock mass structure. Mining influences the dynamic change of the boundary stress field of surrounding rock, causing the convergence curve to fluctuate.