openpit design fundas

Venkat

2

Parts of a bench

Geometrical Considerations

Cumulative frequency

distribution of measured

bench face angles (Call, 1986).

3

Section through a working bench.

Functioning of catch benches.

Geometrical Considerations

4

Double benches at final pit limits. Catch bench geometry (Call, 1986).

Typical catch bench design dimensions (Call, 1986).Bench height Impact zone Berm height Berm width Minimum bench width

(m)153045

(m)3.54.55

(m)1.523

(m)45.58

(m)7.51013

Geometrical Considerations

5

Safety berms at bench edge

Geometrical Considerations

6

Height of reach as a

function of bucket

size.

Geometrical Considerations

7

Example orebody geometry.

Ramp access for the example orebody.

Blast design for

the ramp

excavation.

Geometrical Considerations

8

Shovel Working Range

9

Minimum width drop cut

geometry with shovel

alternating from side to side.

Geometrical Considerations

10

Minimum width drop cut

geometry with shovel

alternating from side to side.

Geometrical Considerations

11

Isometric view of the ramp in

waste approaching the

orebody.

Diagrammatic

representation of the

expanding mining front.

Geometrical Considerations

12

Dropcut / ramp placement in ore. Expansion of the mining front.

Geometrical Considerations

13

Plan view of an actual pit bottom

Showing drop cut and mining

Expansion (McWilliams, 1959).

Geometrical Considerations

14

Extension of the current

Ramp close to the pit wall

(McWilliams, 1959).

Geometrical Considerations

15

Creating initial access /

benches.

Shovel cut sequence when

initiating benching in a hilly

terrain (Nichols, 1956).Sidehill cut with a shovel.

Geometrical Considerations

16

Detailed steps in the

development of a

new production level.

Geometrical Considerations

17

Parallel cut

with drive by.

Geometrical Considerations

18

Parallel cut with

the double

spotting of trucks.

Geometrical Considerations

19

Parallel cut with

the single spotting

of trucks.

Geometrical Considerations

20

Time sequence

showing shovel

loading with single

spotting.

Geometrical Considerations

22

Time sequence

showing shovel

loading with double

spotting.

Geometrical Considerations

23

(Continued).

Geometrical Considerations

24

Geometrical Considerations

(Continued).

25

Section and plan views through a working bench.

Simplified presentation of a safety berm.

Geometrical Considerations

26

Initial geometry for the push back example.

Cut mining from bench 1.

Cut mining from bench 2.

Geometrical Considerations

27

Overall slope angle.

Safety bench geometry

showing bench face angle.

Geometrical Considerations

28

Overall slope angle with ramp included.

Interramp slope angles.

Geometrical Considerations

29

Overall slope angle with

Working bench included.

Interramp angles associated with

the working bench.

Geometrical Considerations

30

Overall slope angle with

one working bench an a ramp section.

Interramp slope angles for a slope containing

a working bench and a ramp.

Geometrical Considerations

31

Overall slope angle for a

slope containing two

working benches.

Geometrical Considerations

32

Slopes for each working group.

Geometrical Considerations

33

Final overall

pit slope.

Geometrical Considerations

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