Institut za rudarstvo i metalurgiju Bor

number of samples so that the deviations
are large. Table 1 gives an overview of the
Table 1. Physical - mechanical characteristics of working samples
Sample
Volumetric weight
kN/m 3
results of statistical analysis of laboratory
geomechanical tests [2].
Angle of internal friction
No 1,2010. 76
MINING ENGINEERING
φ °
Cohesion
kN/m 2
Quaternary 17.74 18.5 18.40
Clay marl 17.37 28.8 1 382.50
Interlayer clay 19.81 19.5 16.22
Coal 13.62 18.5 18.40
Coal clay 18.31 16.6 20.98
Floor clay 20.95 16.6 23.52
Lime stone 25.83 39.2 657.97
Dumped
material
19.90 18.4 19.76
The exact level of ground water in the
“Potrlica” deposit is not known.
In hydrogeological terms, quaternary,
clay marl, coal strata, and limestone and
dumped material are water permeable,
while the clay is waterproof material.
The effect of ground water on the stability
was modeled by the coefficient of
pore water Ru. Stability analysis was done
for the coefficient of pore water Ru with the
value variation from 0 to 0.5 with step 0.1.
Volume of waste dump is 14 200 000
m 3 . The bottom of waste dump is at elevation
K+610 m, and the final plateau of
dumping at K+800 m. Bench height at
waste dump is 10 m. Position of critical
profile for stability analysis is shown in
Figure 1 [1].
Figure 1. Position of critical profile for stability analysis of
internal dump”Kutlovaca”