9
closest to the borehole. The red X’s in Figure 12(a) and
12(b) show the field measurement of the permeability val-
ues after mining the first and second panels in the model.
The modeling results are shown by circles for permeability
of sub-vertical fractures and by squares for the permeability
of bedding planes. The first and last records of permeabili-
ties in the field are considered as the pre-mine-by and post-
mine-by permeabilities, respectively. Figure 12c shows the
permeabilities after the third panel is mined. Table 2 lists
the predicted values by the model and field measurements.
Field measurements will continue during the third
panel mining, and the results will be compared with values
in Table 2 in future works. The results listed in Figure 12
and Table 2 show a good agreement between the predicted
values in the model and the measured values in the field.
CONCLUSION
A comparison was made between field measurements and
the modeled values of rockmass permeabilities above the
abutment pillar in a longwall mine in the Pittsburgh coal
Figure 11. 3DEC results on the aperture values in mm for all fractures (a) after mining the first panel (b) after mining the
second panel (c) after mining the third panel
closest to the borehole. The red X’s in Figure 12(a) and
12(b) show the field measurement of the permeability val-
ues after mining the first and second panels in the model.
The modeling results are shown by circles for permeability
of sub-vertical fractures and by squares for the permeability
of bedding planes. The first and last records of permeabili-
ties in the field are considered as the pre-mine-by and post-
mine-by permeabilities, respectively. Figure 12c shows the
permeabilities after the third panel is mined. Table 2 lists
the predicted values by the model and field measurements.
Field measurements will continue during the third
panel mining, and the results will be compared with values
in Table 2 in future works. The results listed in Figure 12
and Table 2 show a good agreement between the predicted
values in the model and the measured values in the field.
CONCLUSION
A comparison was made between field measurements and
the modeled values of rockmass permeabilities above the
abutment pillar in a longwall mine in the Pittsburgh coal
Figure 11. 3DEC results on the aperture values in mm for all fractures (a) after mining the first panel (b) after mining the
second panel (c) after mining the third panel