Technology assisting in blast monitoring in opencast mines.

1. Submitted by
Ankit Kumar, Project JRF
Department of Mining Engineering

2. 1.0 Introduction
2.0 Uses of computer aided tools and technology at
different stages of Drilling and Blasting.
3.0 Drilling pattern and blast design.
4.0 Computer aided tool and technology for assisting
execution of blast.
5.0 Technology assisting to monitor Blast output and
Productivity.
6.0 Information on Software used in drilling and
blasting field.

3. 1.0 Introduction
 Mining industry is heading towards a technology driven
optimization process.
 The development and advancement of innovative technology is
essential for the mining industry to be cost effective so that
information can flow back into process for continuous
improvement.
 Monitoring instruments, measurement technologies and
computing tools now have the capabilities to provide a bank of
useful information that has previously been the subject of broad
assumption.
 The basic steps in blast engineering are to design, implement and
observe the outcome of a blast. Recently developed technologies
can enhance and streamline the process for the optimization of
blast fragmentation.

4.  The major developments in the blasting technology can be grouped
according to the blast optimization pyramid .Three main stages of
this pyramid are planning, execution and output of a blast.

5. 2.0 Uses of Computer aided tools and Technology at different
stages of Drilling and Blasting
 Planning and design of blast
 Execution of blast
 Blast output and productivity

6. 3.0 Drilling pattern and blast design
• The blasting engineer faced with the challenge of identifying the
rock mass properties governing the blasting performance in each
situation and to incorporate them in the blast design process.
• Computer aided blast design techniques, numerical blasting models
and expert systems considerably reduce both the cost and time
involved in blast design while increasing the quality of prediction.
• These days computer programs are available with the capability to
develop and edit blast designs graphically and optimize those
designs using the analysis tools.

7. • Field monitoring and control,valuable tools that can be used for
optimization in blast designing are:
 Drill hole Deviation
 Drill Machine Navigation systems
 Drill Monitoring
 Laser Profiling

8. Drill hole Deviation
• Drill hole deviation may be defined as the difference between the
actual and planned location of the collar, the path and the final
destination of the drill hole.
• Mining industry needs to utilize modem drilling machines
equipped with a hydraulic shockwave reflex dampening system
which enables the drill machine to maintain ideal feed force,
drilling straight holes, achieving high drilling rates and drill steel
economy.
• Computerized drilling control in modem machines provides the
ideal combination of feed force, rotation torque and penetration
rates.

9. Drill Machine Navigation systems
• GPS is used to determine the exact collar elevation at each drill
location. The drill monitoring system precisely calculates the
depth of the drill hole and it significantly reduces over and under-
drilling (Hendricks 1999).
• The data on actual drill hole positions and length can be up-
loaded from the drill to mine planning office via the radio
network. The knowledge of actual locations and spacing between
holes facilitates comparison between actual and planed blast
design. GPS-based positioning of the drill provides considerable
benefits including improved accuracy and consistency of the
blast.

10. Drill Monitoring
• The type of instrumentation currently available for monitoring of
drills has been radically changed by the modern electronics and
the development of personal computers and its associated
software. The logged data can be analyzed, summarized by the
personal computer and generated in the form of customized
reports to meet the specific requirements of the mine.
• The drill monitoring systems offer the ability to collect and
transmit to the mine office the information such as drill
production statistics, ore and waste intersections, exact collar
locations, hole positions and depths, maintenance information
and consumable tracking.

11. Laser Profiling
• Tight engineering and field control of the front row of holes is of
vital importance (Smith & Wiegard 1999). If the front row
burdens are excessive, explosive force will cause motion where
there is the least resistance.
• Improperly designed front row can result in some or all of the
following adverse effects:
- Inadequate fragmentation
- Poor energy distribution
- Flyrock
- Backbreak
- Coal damage
• There are several laser systems on the market that allow the
operator to measure the front row burden.

12. 4.0 Computer aided tool and technology for assisting
execution of blast.
 The last decade has shown dramatic progress in the advancement
of blasting technology and the improvement in blasting
performance.
 Bulk loading of explosives
 Initiation of blasts
 Explosive product performance
 Photography

13. Bulk loading of explosives
The equipment utilized to load blastholes has improved in
response to more precise blasting products and programs (Watts
1999). Through new computer-aided design and modular design
capabilities comes the ability to manage a bulk loading system
which creates records of what was loaded, make data transfers to
and from the truck on formulas and densities and to carry out
remote control loading.

14. Initiation of blasts
 The development of electronic detonators has created a new era in
blasting technology, not only providing a high level of safety but
also providing the blaster the opportunity to program every
detonator with an individual delay time, which initiates with
absolute precision.
 It is a well known fact that effective control over blast timing will
enhance blasting re- sults. Electronic Initiation systems provide
the following features which are likely to prove beneficial to the
mining industry (Deacon et al. 1997):
- Increased accuracy in timing,
- Flexibility in programmed delays,

15. Photography
The systems available for photographing a blast can be classified as
follows:
- High speed digital computer images,
- High speed l6mm camera,
- Auto-advanced 35mm camera,
- Normal VHS camera,
- High speed VHS camera.
These photography instruments can be utilized to examine face
velocity and trajectory, burden displacement, fly rock and
stemming ejection. The photography records can be used for
assessment of blasts as well as for comparisons between different
blasts.

16. 5.0 Technology assisting to monitor Blast output and
Productivity.
Ground vibrations and diagnostic monitoring
The new generation of seismographs is becoming smaller in size
and more portable for use. The new analysis software has the
capability to synchronize seismic, acoustic and video signals to
better analzse blast vibration data and perform waveform
modelling.
The seismographs are used not only for blast vibration but also for
diagnostic monitoring to determine the cap scatter, misfires,
sympathetic detonation.

17.  Rock fragmentation assessment
The photoanalysis is one of the more recent methods, where
photographic images of blasted rock are analyzed through
computer image processing techniques. Now the blasted rock can
be characterized by completely automated and fully integrated,
PC based fragmentation analysis system using state-of-the-art
photoanalysis techniques. These systems come with high-tech
micro-processors, a dedicated image capture board, fast video
accelerators and specially designed software to measure the rock
fragments and to display and/or print the data in an easy to use
form. The results can be displayed as a histogram or cumulative
weight percent passing curve.

18. The main advantages of these systems are:
- No interference with the mining operations,
- Reproducible results,
- Minimizes entry into hazardous locations,
- Fragmentation parameters can be included in a mathematical
model.

19. 6.0 Information on Software used in drilling and blasting
field.
With the advancement of technology, many software are
developed that help in blast design and its impact assessment
some are as follows:
 JK SIM BLAST
 I-BLAST
 ALPHA BLAST
 BLASPA INC.
 DNA BLAST TECHNOLOGY
 FRAGLIST