爆破作用下金属矿山围岩稳定监测点优化布置

利用矿山现场取得的爆破地震波,结合矿山的实际开采状况,对爆破作用下金属矿山围岩稳定的监测点进行优化布置研究.为了分析爆破作用对地下金属矿山围岩稳定性的影响,截取矿山具有代表性的VII-2矿体剖面,利用光纤光栅传感器对现场爆破作用下的围岩应变进行监测,对爆破作用下围岩的稳定性进行数值模拟计算.依据数值模拟计算结果对围岩监测点的布置位置进行优化.研究结果表明,光纤光栅传感器对爆破作用造成的矿山围岩微应变能够有效的监测,利用光纤光栅进行矿山围岩稳定性监测是可行的.依据爆破前后巷道的位移、应力、加速度和速度变化规律,在布设传感器监测点时将规律点和关键点相结合,定期监测和长期监测相结合,可以更有效地进行地下金属矿山围岩稳定的监测.并适当增设补充点,能够对巷道监测关键点的布置进行有效优化,提高监测的针对性.在实际应用中,应结合应用现场的实际地质条件,在节理和裂隙发育或存在大断层区域增设监测点,以保证监测数据的完整和决策的正确.

Optimization of monitoring points of surrounding rock stability on blasting in underground metallic mine

Combined with the practical exploration approach, the monitoring points optimization of surrounding rock stability was computed by numerical simulation using the earthquake wave got from the site. In order to study the effect of the blasting on stability of surrounding rock in underground metallic mine, fiber grating sensing system was used to monitor the strain of the surrounding rock on the effect of the blasting on a typical cross-section VII-2 in mines. According to the result of the numerical simulation, the layout of the sensors was optimized. The presented work shows the fiber grating sensing system is able to monitor the micro-strain of the surrounding rock caused by blasting. It is feasible to use the fiber grating sensing system to monitor the stability of surrounding rock in underground metallic mine. When disposing the monitoring point of sensors, the regular point is combined with the key point and periodical monitor is combined with the long term monitor. According to the change regularity of the displacement, stress,acceleration and velocity of tunnels before and after explosion, the layout of the monitoring key point is optimized which can improve the aim of monitor. In practical application, monitor points should be distributed at the joints and large faultage to assure the integrity of monitor data and preciseness of decision combined with the geology condition in site.