| 摘要 |
A method for measuring relative changes in stress in front of a longwall wherein a capture-control server (6) records vibration measurement signals from 3-axis geophones (19) installed in longwall galleries (A), in close correlation with signals informing about the operation and position of a shearer (15) in the working (B), in cooperation with a processing server (10) it localises seismic phenomena. After the end of each cut by the shearer (15) it analyses relative changes in stress in the body of coal (C) in front of the longwall with attenuation-damping tomography involving analysis of seismic waves (FK). After ending the cut, during the shearer (15) standstill, it performs active velocity/attenuation tomography by seismic imaging of the rock mass between the longwall galleries (A) using seismic waves (FS), and then analyses the stress with passive velocity/attenuation tomography using seismic waves (FP). Then periodically, preferably several times during one mining shift, the averaged cumulated tomographic maps of relative changes in stress, and/or maps of particular tomographies are drawn. A corresponding system is provided. |
