| 摘要 |
A method for measuring relative changes in stress in front of a longwall is characterized in that the capture-control server (6) records the vibration measurement signals from the 3-axis geophones (19) installed in the longwall galleries (A), spatially oriented synchronously in all channels and in synchronized time interval, and in close correlation with the signals informing about the operation and position of the shearer (15) in the working (B) and on this basis, in cooperation with the processing server (10) it localizes the seismic phenomena. After ending of each cut by the shearer (15) it analyzes 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 of the cut during the shearer (15) standstill, it makes the active velocity or attenuation tomography by seismic imaging of the rock mass between the longwall galleries (A) using seismic waves (FS), and then analyzes the stress with passive velocity and / or 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 the maps of particular tomographies are drawn. The system comprises at least six universal initiation and vibration measurement modules (1) arranged in each of the longwall galleries (A), which are connected via intrinsically safe digital transmission lines (2) to a local measurement data concentrator (3), which is connected to an intrinsically safe power buffer supply (4) and via the optical Ethernet network (5) to the capture-control server (6) connected to the mine dispatching system (7), the global satellite positioning module (8), the internal time module (9) and the processing server (10). The processing server (10) is connected to the cumulated tomography visualization panel (14) and preferably to the active attenuation-damping tomography visualization panel (11), the active velocity or attenuation tomography visualization panel (12), and the passive velocity or attenuation tomography visualization panel (13). |
