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By Brian Gar Wingfield

Bulk explosive systems have developed from the infancy stages in the early sixties to a sophisticated process of the nineties. With ever changing bulk explosives technology, bulk delivery and loading systems needed to keep pace. Efficiency, as compared with packaged loading, was the keyword allowing faster loading of trucks and shots. Efficiency was also improved by the explosives coupling factor that bulk loading permitted.

Jan 1, 1991

By Mick Fritz, Tom Treleaven

The success of any blast is dependent on the accuracy of the blast design and field controls placed at the shot location. The procedure by which the data is collected and analyzed is paramount to accomplishing the anticipated blast results. lf the geometry of the blast is not measured correctly, then the results will not meet expectations. Measuring the geometry and compensating for bole hole deviations is crucial not only to the lnitlal blast but also for any consecutive blasts. Excessive bore hole deviation can cancel any new technology in use. However the instruments and skills required solving this Issue are readily available.

Jan 1, 1998

By Rudi Toba

Several areas at the DOZ haulage were observed for the crusher’s location. Initially the new crusher designed position was west of the crusher 1, but due to concerns of the mine crack zone (deep MLZ) the crusher position moved to the south. The new crusher location is situated in a diorite rock massive between 3053 – 3079 levels, with the overall excavation of 2500 cum and dimension of 14m long, 14 m wide and 14 m high. Main Crusher chamber itself excavated by development jumbo in three lifts. Development of access to the bottom crusher was developing the same time as chambering the top crusher. The pocket of the crusher mined with vertical crater retreat system which is initiated in one time after middle slot raise. Collaboration between production and perimeter blast holes to be obtaining in control the actual cuts as per the design shape.

Jan 1, 2007

By Gilberto Nunez, Ron Eastman, Hector Parra

The prediction of blasting outputs has proven to be a sound engineering tool to provide a guideline for design improvement. It has also been demonstrated to be extremely useful in critical situations when production can be compromised and there is no chance for error.

Jan 1, 2015

By Brian Wingfield, Greg Williams, Richard W. Givens

Application of required energies into the rig design can have a dramatic impact upon productivity. Computer modeling of these production variables has led to changes in design with values closely approaching actual field data. Knowledge of these required energies can also specify the proper drilling technique to the application. With this knowledge, productivity-to-cost ratios can be determined with the most efficient option chosen.

Jan 1, 1995

By Mike Higgins

"Data management is emerging as a major concern for miners. Engineers today are faced with anextensive array of data from varying sources, and are required to consolidate and analyse thisinformation to produce an effective and efficient mine plan. The viability of a mining operation canbe dependent on the outcomes of this process. With so much at stake, it is no surprise that mostengineers prefer a standard approach to blasting which is designed to minimise risk rather thanoptimise performance."

Jan 1, 1998

By Shi Hongchao, Zou Zou Xinkuan, Zhang Jichun

As drilling and blasting is carried out in an urban tunnel, which is adjacent to an existing building or structure, the balance between blasting-induced vibration reduction and drivage efficiency is a most important issue that must be resolved properly. Therefore, a new cut blast method named Stepped V-cut millisecond blasting (SV-cut) was developed by optimizing the most common used Vertical V-cut blasting method (V-cut). The most significant features of SV-cut lie in the utilization of sublevel interval charging structure and millisecond delay blasting technology in cut hole and the cut-cavity formed from outside to inside sequentially. SV-cut provides advantages of high borehole using ratio, low vibration level, and satisfied advance per attack. Based on the principal of millisecond blasting, the rock fragmentation process and the vibration reduction mechanism of SV-cut are analyzed. Determining methods of blasting parameters, which do have significant effect on vibration intensity and cut-cavity formed quality, are proposed according to the forming requirement of both outer and inner cut-cavity and vibration reduction. In order to compare the performance between SV-cut and V-cut, field blasting experiments were performed in the blasting engineering of Yamalike twin-arc tunnel, which closely passes over aged parallel tunnels. Blasting results show that SV-cut blasting is proven as an effective tunnel blasting method for both increasing blasting effects and decreasing blasting vibration. Comparing SV-cut with V-cut, the SV-cut can increase blasting drivage about 8.5% and reduce the vibration intensity induced by cut hole blasting 30% at least.

Jan 1, 2015

By Robert Morgan

With improved methods for designing and detonating shots the potential for flyrock can be significantly decreased, but there are few absolutes in blasting; therefore blasters must learn from the mistakes of others. Blasters must conscientiously employ control measures to minimize the risk of flyrock. The worst case incidents which tend to be widely reported by the media, should serve as a reminder to us all that minimizing the risk of flyrock must be incorporated into the design of the drill pattern and blast design.

Jan 1, 2001

By D Vidyarthi

Blasting is the most important activity in the mining industry, the world over. It is a well known fact that only part of the explosive energy gets utilized in causing the actual rock fragmentation. The rest of it gets converted into blast-induced ground vibrations and noise. Though blast vibrations cannot be totally eliminated, it is possible to minimize them by optimization of blast parameters. This paper highlights various in-house efforts put forth by the author towards site specific blast optimization and the monitoring of blast vibrations. It also deals with the prediction curves developed by regular regression analysis for the prediction of ‘blast vibrations’, ‘peak particle velocity’, ‘safe charge’ for various blasts.

Jan 1, 2007

By Clarence R. Zink

A problem has always existed in deep and fast drilling situations such as coal overburden drilling, or when drilling with a tight annulus, such as 9 7/8" bits and 8 5/8" pipe. This problem is the difficulty experienced by blasthole bit and blasthole drill rig manufacturers to attain large jumps in bit and drill rig productivity through bit and rig design, when drilling in these specific situations. In other drilling situations, these large jumps in productivity have been easily attained.

Jan 1, 1998

By K B. Holm

This paper deals with the advances made at Syferfontein Colliery in the calculation and control of dragline methodology. The high capital outlay and operating cost of a dragline necessitates strict control of all aspects of the dragline operation. Before purchasing a dragline, a complete evaluation of all the parameters that can affect the viability, now and in the future, of the dragline operation needs to be completed. Such parameters as thickness of burden, material properties (swell), “castability”, pit width and pit length, etc. need to be considered.

Jan 1, 1994

By Randal Martin

Recently, questions regarding the influence of atmospheric temperature and humidity levels on airblast levels have arisen at a number of blast sites. Humidity is alleged to have contributed to high levels of disturbance within communities surrounding blasting. In some cases, local regulatory agencies considered adopting guidelines to specify humidity and temperature ranges under which blasting cannot take place. However, it is normal blasting industry practice not to consider humidity or temperature effects, in the absence of inversions, on airblast levels. When blasting is conducted in the vicinity of residential structures, the influence of weather on the propagation and attenuation of airborne noise from the blasting site is always a concern. Sound naturally attenuates in air with distance from the source. A part of this attenuation is attributed to divergence at the airblast wave front, while the remainder of the attenuation is an accumulation of various factors that include temperature and barometric pressure, absorption in air due precipitation and vegetation, wind and temperature gradients, atmospheric turbulence and topography (Beranek, 1971). Wind speed and wind direction, as well as vertical and horizontal temperature gradients can cause airblasts to focus in local regions surrounding blasting operations and may result in air pressures greater than expected. In fact, wind and temperature inversions can actually increase sound levels with distance from the blast site. Close to the blast site, the effects of inversions may be negligible but may exceed 10 dB at 800 m or greater (Davis and Cornwell, 1991).

Jan 1, 2001

By Don Novotny, Dana Spencer

In this workshop our intent is quite simple; that is that we will introduce a relatively new technology that may have applications in blasting applications. This technology is the laser initiation of explosives. This workshop course is not intended to suggest ways in which specific blasting problems can be resolved. That is the purview of experts within each of your fields.

Jan 1, 1994

By Michael D. McGill, Jeff Freadrich

There are many factors which affect the productivity of a front end loader. One of the most obvious is the characteristics of the material being mined. Characteristics such as size distribution, swell factor or heave, and material hardness / abrasiveness will all effect the efficiency of the mucking cycle. The focus of this paper is to look specifically at the size distribution of blasted material, and quantify the effects on loader productivity.

Jan 1, 1994

By Christopher Cloete Uys, Luis Manuel Poinha Valentim

The purpose of this workshop is to describe and demonstrate the use of SPEEDWAVE, a high speed data recorder, its VOD enhancements, and the software which binds the system together. The system was designed by TLC Sohware, SOUTH AFRICA. TLC is a company spedalising in the solution of engineering problems, using computertechnology as a base. TLC was founded in 1987, and has since been involved in many different.measurement, control, simulation and modelling projects. Wth respect to the blasting industry, TLC has, in conjunction with AECI South Africa/ICI, developed a tunnel mining design aid, a ring blasting design aid, a multkhannel seismograph and a laser surveying program. In 1989, TLC designed and built the BA800. a microcomputer-based high speed recorder. These recorders are still in use and are producing valuable results. Based on improved technology and with the field experience of the BA800, TLC has designed and developed the data recorder SPEEDWWE.

Jan 1, 1995

AQUILA Mining Systems Ltd., designs, develops and delivers systems for measurement, analysis, simulation, control and automation to the mining, construction and petroleum industries. The objective of current efforts by AQUILA is the continued development and refinement of computerbased systems and techniques to automatically process monitored performance data from surface blasthole drills and mining shovels, and the management and coordination of these pieces of equipment by GPS (Global Positioning Systems).

Jan 1, 1994

By Bruce Vandenberg, Andy Bartfay-Szabo, Steve Conway

Recent advances in solid-state, field portable, fast framing video camera systems and PC based frame capture hardware now allow blast imaging up to 500 frames per second. Up to 8 seconds of data can be stored directly into the unit, downloaded to a PC or archived to a standard VCR without data compression. Since no film processing is involved, motion analysis can be performed instantly and on-site within a few minutes. This paper will describe the design features and applications of the SVClOOO system and compare these with the analogous aspects of film based cameras.

Jan 1, 1995

By Tom Short

"Construction blasting covers a very extensive variety of explosive applications. I will discussseveral of these with you and then show slides from my collection, starting in 1956, which will betterillustrate the types of blasting under discussion."

Jan 1, 1991

By J Lyall Workman, Peter N. Calder

"Large hole rotary drilling is one of the most common methods of producing blastholes in open pitmining. Large hole drilling generally refers to diameters from 9 to 17 inch (229 to 432 mm), however aconsiderable amount of rotary drilling is done in diameters from. 6% to 9 inch (165 to 229 mm). Thesesmaller diameters are especially prevalent in gold mining and quarrying."

Jan 1, 1996

By Peter Reinders, Dirk Hummel

This paper describes a newly developed Surface Remote Blasting System (SURBS) for electronic detonators, which is currently being introduced into surface blasting applications. The rationale for developing the SURBS was to meet key needs of mine operations, such as minimizing the shutdown time and the capability to conveniently initiate blasts in difficult terrain from a safe distance. Increased distance from the blast site, combined with a good overview of the site enables maximum safety during blasting. The system also removes the inconvenience of running long firing cables. The SURBS consists of the field-proven detonator and equipment technology of an existing electronic detonator system, a Surface Remote Blasting Box and a Surface Remote Blaster. The Surface Remote Blaster is the Master unit and controls the Remote Blasting Box via encrypted radio communication using a sophisticated safety technology, which guarantees that the highest safety standards are maintained.

Jan 1, 2005