小厂坝矿区地应力测试及分布规律

In-situ Stress Test and Distribution Law in Xiaochangba Mining Area

AE法测地应力由于Kaiser效应点难以辨识,应用受到极大限制。通过解决MTS815加载系统与PCI-Ⅱ型声发射信号采集系统在时间上的同步问题,确保了测试的Kaiser效应点与实际的Kaiser效应点的一致性;提出了分级循环加载精确识别地应力Kaiser效应点的方法。将该方法用于小厂坝矿区15个测点地应力测试中,其结果表明,小厂坝矿区主要以水平构造应力为主,但随着开采深度的增加,地应力由水平构造应力为主向垂直应力为主转变;750m中段的水平最大主应力超过30MPa,说明750m中段存在发生岩爆的高应力环境,在实际开采中,应加强支护和监测。

By using AE method to measures the in-situ stress,the kaiser effect point is difficult to identify,and the application is greatly limited.First,the consistency of the Kaiser effect point of the test and the actual Kaiser effect point is ensured by solving the time synchronization problem between the MTS815 loading system and the PCI-II type acoustic emission signal acquisition system.A method of accurately identifying the Kaiser effect point of in-situ stress by staged cyclic loading is put forward and it is applied to the in-situ stress test of 15 measuring points in Xiaochangba mining area.The results show that the Xiaochangba mining area is mainly dominated by horizontal tectonic stress.Domination of in-situ stress shifts from horizontal tectonic stress to vertical stress with the increase of mining depth.The horizontal maximum principal stress of the middle section of 750m exceeds 30MPa,and it means section of 750m has a high stress environment for rock burst.The support and monitoring should be strengthened in actual mining.