关键词: Mathews稳定性图, 数值模拟, 锚索支护, 水平位移, 塑性区

Abstract: Taking the underground mining transferred from open-pit in Qinglonggou gold mine as the engineering back ground，the scan-line survey method is employed to make engineering geological investigation and obtain the discontinuity in formation，and rock mechanics testing in laboratory were carried out to classify the rock mass and estimate their properties ac cordingly. The Mathews stability graph method is adopted to calculate that the maximum unsupported lengths of roof，hanging wall and footwall are 52.5 m，35.84 m and 12.11 m respectively. The maximum possible exposure length of the stope is set to 34 m by considering the geological and underground mining conditions. A FLAC3D software was employed to make numerical simulation on the stope structural parameters. The simulation results show that there was a large range of plastic failure at the footwall，which is consistent with that of the stability graph method. The cable bolt support scheme of footwall was put forward by using the empirical method to determine the support parameters of the stope. The numerical analysis on the cable bolt sup port of the stope showed that the the maximum horizontal displacement and the range of plastic zone in the footwall decreased significantly after installing the cable bolt support system. The designed support scheme can ensure the stability of the foot wall. This research provides a reference for determining the stope structural parameters and selecting the support pattern in similar mines.

Key words: Mathews stability graph, Numerical simulation, Cable bolt support, Horizontal displacement, Plastic zone