The Journal of Explosives Engineering - March/April 2013 - 31
ft) benches were the limit of the
current overburden drill, and
produced a less than satisfactory high wall to work beneath.
Subsequent cast shots were not
attempted due to excessively
large toe burdens on the order
of ~16.8 m (55 ft) that were
created from scaling and chain
dragging activities required for
a safe high wall. It was obvious
that cast blasting a single bench
would be the most cost effective
manner to uncover the ore body.
After performing these test shots,
which included blasting both the
high cover and low cover material together, the next challenge
was justifying a bigger overburden drill and angle drill package.
Study on Conversion to
Cast Blasting
Since mining is performed
down a 10% grade (figures 2
and 3) some casting was occurring during the blasting of
the high and low cover and this
motivated the engineers to think
seriously about cast blasting
these two layers together (the
high cover and the low cover
benches). A study was begun to
assess the feasibility of cast blasting including the mechanics of
the overburden movement and
the anticipated benefits. The
mechanics of the overburden
movement were evaluated using
the computer code, DMC (Distinct Motion Code) (Preece, et al,
1993).
Rock laboratory testing was
carried out on samples from
across the geologic stratigraphy.
Testing included: 1) unconfined
compression strength, 2) density, and 3) sonic velocity. These
tests provided the rock material
data needed for the computer
analyses: 1) Young’s modulus, 2)
Poisson ratio, 3) density, and 4)
strength. Table 1 contains the
geologic layers tested and their
approximate thicknesses. These
layers vary some in thickness
and also presence in the geologic sequence across the mine.
The cast blasting study was
carried out in three phases: 1)
DMC modeling of the high cover
March/April 2013
Figure 4. DMC modeling of the high cover blast.
Figure 5. DMC modeling of the low cover blast.
The Journal of Explosives Engineers
31
http://www.isee.org
The Journal of Explosives Engineering - March/April 2013
Table of Contents for the Digital Edition of The Journal of Explosives Engineering - March/April 2013
Call for Papers
From the President
Highlights of the 39th Annual Conference in Fort Worth, Texas
Chapter News
Industry News
Calendar of Events
20th Annual Photo Contest Winners
Explosives, 100 Years Ago, More or Less
Conversion from Two-Pass Overburden Removal to Cast Blasting at Simplot Phosphates
The Journal of Explosives Engineering - March/April 2013 - cover1
The Journal of Explosives Engineering - March/April 2013 - cover2
The Journal of Explosives Engineering - March/April 2013 - Call for Papers
The Journal of Explosives Engineering - March/April 2013 - 2
The Journal of Explosives Engineering - March/April 2013 - 3
The Journal of Explosives Engineering - March/April 2013 - From the President
The Journal of Explosives Engineering - March/April 2013 - 5
The Journal of Explosives Engineering - March/April 2013 - Highlights of the 39th Annual Conference in Fort Worth, Texas
The Journal of Explosives Engineering - March/April 2013 - 7
The Journal of Explosives Engineering - March/April 2013 - 8
The Journal of Explosives Engineering - March/April 2013 - 9
The Journal of Explosives Engineering - March/April 2013 - 10
The Journal of Explosives Engineering - March/April 2013 - 11
The Journal of Explosives Engineering - March/April 2013 - 12
The Journal of Explosives Engineering - March/April 2013 - 13
The Journal of Explosives Engineering - March/April 2013 - Chapter News
The Journal of Explosives Engineering - March/April 2013 - 15
The Journal of Explosives Engineering - March/April 2013 - 16
The Journal of Explosives Engineering - March/April 2013 - 17
The Journal of Explosives Engineering - March/April 2013 - Industry News
The Journal of Explosives Engineering - March/April 2013 - 19
The Journal of Explosives Engineering - March/April 2013 - Calendar of Events
The Journal of Explosives Engineering - March/April 2013 - 21
The Journal of Explosives Engineering - March/April 2013 - 20th Annual Photo Contest Winners
The Journal of Explosives Engineering - March/April 2013 - 23
The Journal of Explosives Engineering - March/April 2013 - Explosives, 100 Years Ago, More or Less
The Journal of Explosives Engineering - March/April 2013 - 25
The Journal of Explosives Engineering - March/April 2013 - 26
The Journal of Explosives Engineering - March/April 2013 - 27
The Journal of Explosives Engineering - March/April 2013 - Conversion from Two-Pass Overburden Removal to Cast Blasting at Simplot Phosphates
The Journal of Explosives Engineering - March/April 2013 - 29
The Journal of Explosives Engineering - March/April 2013 - 30
The Journal of Explosives Engineering - March/April 2013 - 31
The Journal of Explosives Engineering - March/April 2013 - 32
The Journal of Explosives Engineering - March/April 2013 - 33
The Journal of Explosives Engineering - March/April 2013 - 34
The Journal of Explosives Engineering - March/April 2013 - 35
The Journal of Explosives Engineering - March/April 2013 - 36
The Journal of Explosives Engineering - March/April 2013 - 37
The Journal of Explosives Engineering - March/April 2013 - 38
The Journal of Explosives Engineering - March/April 2013 - 39
The Journal of Explosives Engineering - March/April 2013 - 40
The Journal of Explosives Engineering - March/April 2013 - cover3
The Journal of Explosives Engineering - March/April 2013 - cover4
https://www.nxtbook.com/naylor/ISES/the-journal-of-explosives-engineering-november-december-2022
https://www.nxtbook.com/naylor/ISES/the-journal-of-explosives-engineering-september-october-2022
https://www.nxtbook.com/naylor/ISES/the-journal-of-explosives-engineering-july-august-2022
https://www.nxtbook.com/naylor/ISES/ises0422
https://www.nxtbook.com/naylor/ISES/the-journal-of-explosives-engineering-march-april-2022
https://www.nxtbook.com/naylor/ISES/the-journal-of-explosives-engineering-january-february-2022
https://www.nxtbook.com/naylor/ISES/ISES0621
https://www.nxtbook.com/naylor/ISES/ISES0521
https://www.nxtbook.com/naylor/ISES/ISES0421
https://www.nxtbook.com/naylor/ISES/ISES0321
https://www.nxtbook.com/naylor/ISES/ISES0221
https://www.nxtbook.com/naylor/ISES/ISES0121
https://www.nxtbook.com/naylor/ISES/ISES0620
https://www.nxtbook.com/naylor/ISES/ISES0520
https://www.nxtbook.com/naylor/ISES/ISES0420
https://www.nxtbook.com/naylor/ISES/ISES0320
https://www.nxtbook.com/naylor/ISES/ISES0220
https://www.nxtbook.com/naylor/ISES/ISES0120
https://www.nxtbook.com/naylor/ISES/ISES0619
https://www.nxtbook.com/naylor/ISES/ISES0519
https://www.nxtbook.com/naylor/ISES/ISES0419
https://www.nxtbook.com/naylor/ISES/ISES0319
https://www.nxtbook.com/naylor/ISES/ISES0219
https://www.nxtbook.com/naylor/ISES/ISES0119
https://www.nxtbook.com/naylor/ISES/ISES0618
https://www.nxtbook.com/naylor/ISES/ISES0518
https://www.nxtbook.com/naylor/ISES/ISES0418
https://www.nxtbook.com/naylor/ISES/ISES0318
https://www.nxtbook.com/naylor/ISES/ISES0218
https://www.nxtbook.com/naylor/ISES/ISES0118
https://www.nxtbook.com/naylor/ISES/ISES0617
https://www.nxtbook.com/naylor/ISES/ISES0517
https://www.nxtbook.com/naylor/ISES/ISES0417
https://www.nxtbook.com/naylor/ISES/ISES0317
https://www.nxtbook.com/naylor/ISES/ISES0217
https://www.nxtbook.com/naylor/ISES/ISES0117
https://www.nxtbook.com/naylor/ISES/ISES0616
https://www.nxtbook.com/naylor/ISES/ISES0516
https://www.nxtbook.com/naylor/ISES/ISES0416
https://www.nxtbook.com/naylor/ISES/ISES0316
https://www.nxtbook.com/naylor/ISES/ISES0216
https://www.nxtbook.com/naylor/ISES/ISES0116
https://www.nxtbook.com/naylor/ISES/ISES0615
https://www.nxtbook.com/naylor/ISES/ISES0515
https://www.nxtbook.com/naylor/ISES/ISES0415
https://www.nxtbook.com/naylor/ISES/ISES0315
https://www.nxtbook.com/naylor/ISES/ISES0215
https://www.nxtbook.com/naylor/ISES/ISES0115
https://www.nxtbook.com/naylor/ISES/ISES0614
https://www.nxtbook.com/naylor/ISES/ISES0514
https://www.nxtbook.com/naylor/ISES/ISES0414
https://www.nxtbook.com/naylor/ISES/ISES0314
https://www.nxtbook.com/naylor/ISES/ISES0214
https://www.nxtbook.com/naylor/ISES/ISES0114
https://www.nxtbook.com/naylor/ISES/ISES0613
https://www.nxtbook.com/naylor/ISES/ISES0513
https://www.nxtbook.com/naylor/ISES/ISES0413
https://www.nxtbook.com/naylor/ISES/ISES0313
https://www.nxtbook.com/naylor/ISES/ISES0213
https://www.nxtbook.com/nxtbooks/naylor/ISES0113
https://www.nxtbook.com/nxtbooks/naylor/ISES0612
https://www.nxtbook.com/nxtbooks/naylor/ISES0512
https://www.nxtbook.com/nxtbooks/naylor/ISES0412
https://www.nxtbook.com/nxtbooks/naylor/ISES0312
https://www.nxtbook.com/nxtbooks/naylor/ISES0212
https://www.nxtbook.com/nxtbooks/naylor/ISES0112
https://www.nxtbook.com/nxtbooks/naylor/ISES0611
https://www.nxtbook.com/nxtbooks/naylor/ISES0511
https://www.nxtbookmedia.com