爆破回采对某金属矿深部采场围岩稳定性的影响

Effects of Blasting Mining on the Stability of the Surrounding Rock Masses in a Metal Mine

深部岩体处于高地应力、高温、高孔隙压力的环境。这使深部岩体的组织结构、基本行为特征和工程响应均发生根本性变化,也导致深部开采中灾变事故的出现。为了控制深部采场回采过程中的某金属矿深部采场的围岩稳定性,也为改善深部开采采矿技术经济指标,结合实际利用有限元程序,对某矿爆破回采过程进行数值模拟,分析采场顶板和间柱的应力场、位移场和塑性区,爆破作用对顶板和间柱造成的损伤作用。研究表明,采场经过爆破回采作业后,水平及竖直向应力场的区域及位移场的区域并没有发生明显改变,只是在数值上有所增加。但塑性区发生明显变化。分析结果对采场的稳定性研究及地表沉降研究提供了参考。

The rock body in depth lies in an environment of high ground pressure,high temperature and high pore pressure,this causes a change of deep rock in mechanical structure,basic behavior characteristic and response to consturction,and also the appearance of calamity during deep mining.In order to control the stability of surrounding rock mass during mining and improve deep mining technical and economic indexes,the deep blast mining process of certain mine is simulated by using FEM.The distribution of stress,displacement and plastic zone of roof and rib pillar of stope is obtained.Moreover,the damage of surrounding rock mass is analyzed.The results show that there are no obvious change in distribution of the horizontal and vertical stress and displacement fields,only their magnitude increases.But the change of plastic zone during mining is obvious.The numerical results can serve as reference in study of the stability of stope and surface subsidence.