depth optimisation using udec software

1. OPTIMISATION OF DEPTH
OF O/C COAL MINE USING
UDEC SOFTWARE
PROF. IN-CHARGE
Dr. S. S. Gupte

2. • In India, the number of operating opencast mines is
steadily increasing as compared to underground
mines. It is due to low gestation period, higher
productivity, and quick rate of Investment.Large
number of opencast mines are now days reaching
to deeper mining depths. As a result analysis of
stability of operating slopes and ultimate pit slope
design are becoming a major concern.
INTRODUCTION

3. OBJECTIVE
• Designs of stable slopes for
opencast COAL MINES
using UDEC SOFTWARE at
greater depth
• Understanding different
types and modes of slope
failures with increasing
depth
IMPORTANCE OF PROJECT
• Reduced chances of slope
failure
• Better utilisation of
machinery and equipment
• Increased monitoring of
sides and slope
• We can extract more ore
from mine using this
method(as we go deeper)
i.e. optimisation of depth

4. Analysis procedure using
UDEC SOFTWARE
Divided into 4 stages
MODELS STAGE
BUILD STAGE
SOLVE STAGE
PLOT STAGE
Accidents in o/c coal mine
(unstable slope)
Mine Name No of
people
died
year
Kawadi o/c mine 10 2000
Mahakali mine 8 1923
Dhori mine 7 1923
Mithapur mine 4 1950
Jamuna mine 6 1963
Jayant o/c project 5 2008

5. BUILT STAGE

6. SOLVE STAGE

7. PLOT STAGE

8. Problems and constraints in deep open
cast mines.
1. Stability of Benches
• As depth increases stress
levels increases in slopes
and it is obvious that
chances of failure will be
greater.
• This will be enhanced due
to weight of the upper
benches and movement of
heavy machinery as well.
2. Transportation
• The standard sized dumpers
and machinery may have to
be replaced with heavy duty
versions.
• Bigger size machinery needs
larger width of of haul
roads.

9. (3) Ventilation
• Natural ventilation in
deep mines is of great
concern as deep mines
will have have
inadequate fresh air at
the pit bottom.
• Exhaust from machinery
and dust clouds in
mines adds to the
worsening of the
situation
(4) Drainage
• As mines go deeper
and deeper, problem of
water accumulation
also rises.
• Also if the mine
intersects any aquifier
while excavation, may
lead to flooding of the
mine

10. (5) BLASTING
• To have stable slopes,
having large no. of small
benches may be a good
option.
• For creation of these
benches frequent
blasting is required.
• Due to this
transportation cost and
workload increases
(6). Backfilling at lower
levels
• Backfilling at deeper
depths along with high
dip angle of the ore
body is difficult.
• When the dip is high,
less effective space is
available for
accomodation of the
over burden

11. (7) Impact on water regime
• Deep surface mines affects the hydrological
regime and quality of the surrounding water.
• Lot of water is used in mining activities.
• Water collected in the sump is partly used and
discharged on the surface.
• This leads to pollution of water on surface.

12. Failure analysis method
• Stereographic Solution
• Toppling Failure Analysis
• Circular Failure Analysis
• Limit Equilibrium Method
• Stress Analysis Method

13. WAYS TO REDUCE THE CHANCES OF
SURFACE GROUND CONTROL FAILURE
• Safe geotechnical design
• Provide secondary support
• Monitoring devices for advance warning of
impending failure

14. JAI JAIN
AMEYA TELANG
B. VENKETESH PRASAD
Thank you