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By Dale Preece, Stephen Chung, Richard Jensen

DMCBLAST_3D is a three-dimensional extension of the proven two-dimensional rock blast modeling code, DMCBLAST. DMCBLAST has been under development since 1987 and has successfully predicted the physics, mechanisms and results of a number of different types of rock blasting including, coal mine bench blasting, mineral mine choke blasting and underground stope blasting. Substantial effort has gone into the qualification and verification of DMCBLAST by comparing computer code predictions with real blasts in the field. Comparison with field data has also provided significant guidance to the development of the code.

Jan 1, 2001

By Trevor Garbutt, Peter Bellairs, Jason Sander, Glenn Shaw

The Yarrie Iron Ore mine is located in the Pilbara region of Western Australia some 200km eastsoutheast of Port Hedland, the closest large regional centre. The mine is owned by BHPIO who has contracted a large Australian mining contractor Roche Bros to be responsible for the total mining, crushing and trainloading functions. This paper describes a drill and blast optimisation program, resulting from the introduction of a new emulsion matrix called Titan@ Red used to manufacture both HANFO and pumped emulsion ANFO blends.

Jan 1, 1999

By Chapman Young, William L. Fourney, Richard D. Dick

During 1981 and 1982, an extensive oil shale fragmentation research program was conducted at the Anvil Points Mine near Rifle, Colorado. The primary goals were to investigate factors involved for adequate fragmentation of oil shale and to evaluate the feasibility of using the modified in situ retort (MIS) method for recovery of oil from oil shale.

Jan 1, 1985

By Dale S. Preece, Stephen H. Chung

"In bench blasting, the distribution of loaded explosives with respect to the burden rock has strong effects on digging especially at the toe area. Blast design often focuses on other results such as percent-cast or fragmentation, sometimes leaving a diggability problem at the toe of the blast that is not discovered until excavation. A method for assessing the influence of blast design on diggability has been developed. This method relates the kinetic energy and rock displacement experienced by the material in the muckpile to its diggability. Simulation of the blast along with the calculation of kinetic energy and diggability is done with the discrete element computer program DMC_BLAST(DMC: Distinct Motion Code)."

Jan 1, 1999

The most common method for identifying the potential for blast damage is the peak particle velocity. But this can depend on many factors such as the type of blast, explosive, confinement, timing and the rock mass. The value must then be used to estimate damage. But the amount of damage will depend on the rock mass quality and the excavation size and shape. The amount of damage that can be accepted will depend on the purpose of the excavation. This paper presents a logical, but very approximate, procedure that the mining engineer can follow in order to assess the potential for damage in the control of that blasting.

Jan 1, 1987

By Terry Graf, Bill Thompson, John Guenther

SYNCRUDE CANADA LTD.. operates the largest synthetic crude oil production facility in the world. Over 60,000,000 Bank Cubic Metres of oil sand is mined each year from their open pit located in Fort McMurray, Alberta. Despite the extremely cold temperatures encountered during the winter months and the problems associated with frost buildup, SYNCRUDE has continued to operate on a 12 month per year basis. In 1989 SYNCRUDE mine management embarked on a comprehensive Frost Blasting program to improve mine production of their oil sand moving equipment. The following paper will discuss the development of their frost blasting program to its current status.

Jan 1, 1993

By J R. "Dick" Daniel

In the fall of 1988, The Cannon mine decided to investigate a central blasting system based on conventional electric blasting detonators being used to initiate rounds primed with Nonel detonators. The advantages of this hybrid detonator system were viewed as being safety and cost effectiveness. A study was done reviewing the safety aspects of utilizing a permanent blasting line installed throughout the main haulage drifts to a central blasting station located at the mine portal. The study addressed the following potential safety hazards: radio frequency induced current, stray current from both electrical utilities and transmission lines, galvanic and electrostatic sources of extraneous current.

Jan 1, 1989

By D. Bartley, R. McClure, W. Reisz

Ever since the 8ms criterion was developed in the early 60’s there has been an ongoing debate among many blasters as to its actual value in controlling ground vibration. The perpetuation of the myth surrounding the 8ms window can be partly attributed to its simplicity and convenience as a means for regulatory compliance. Unfortunately, the mindset that many blasters have adopted has hindered the development and use of more effective techniques and in many cases can actually be counter productive to vibration control.

Jan 1, 2006

By Rolf R. Schillinger

It is established to an increased extent that the basic questions about raw material extractions deal with water, dust, noise and vibrations. If it has not been definitely proven that these points won?t lead to excessive environmental strains, attempts at any explanations will meet with disapproval in advance. In order to answer the basic questions about dust, noise and vibrations quality management becomes most important, particularly with respect partly unavoidable emissions of production processes. The specific questions have to be answered within the context of good blasting practices, latest discoveries of the explosives industry, and by use of a Blasting Works Quality- Management, which includes both production quality and Risk-Management. The paper shows a practical way to work out a Quality-Management Program for companies involved in blasting activities.

Jan 1, 2002

By Clarence Zink

The need for continual process improvement and innovation to reduce operating costs in the mining industry extends to the first significant encounter all production miners have with the rock: drilling blastholes. Material and design advances alone have greatly increased the productivity of today's tricone blasthole bit over bits used just a few years ago. Significant additional operating savings are being realized by utilizing improved air practices on blasthole drills, and by selecting drilling equipment designed to provide optimum air volume and pressure at the blasthole bit.

Jan 1, 1997

This case history refers to the detonation of the two largest chemical explosions on the Australian continent. An important element of feasibility studies and construction guidance included prediction of fragmentation results and ground vibration effects for the detonation of two very large "coyote" blasts, consisting of mined tunnels filled with explosives. The larger of the two blasts contained nearly 1 1/4 million pounds of explosives detonated instantaneously. The explosives were placed in specially designed tunnels under a quartzite mountain for the purpose of generating rock fill for the main dam on the project.

Jan 1, 1995

By Erik Nygaard, Klaus Voges

ANFO is the most used industrial blasting agent in the world, and is often used as a reference for comparison of other explosives. It is known to work very well under dry conditions in large borehole diameters, whilst in small borehole diameters increasing amounts of toxic fumes (CO, NO and NOz) can be formed. In underground blasting, problems can also occur with reduced visibility caused by unreacted ammonium nitrate and overall composition of the detonation fumes. ANFO is made by mixing Ammonium Nitrate Porous Prills (AN-PP) and fuel oil. We have measured velocity of detonation (VOD), toxic fumes and visibility after blasting of ANFO in 54x2 mm steel tubes, and the differences are remarkable: By using an AN-PP grade developed for underground blasting and small diameters, the following can be obtained:

Jan 1, 2001

By S. J. Dillingham

One of the primary goals of every blaster is to achieve the optimum blast design. Too much focus on efficient design, however, can cloud certain issues and exposures that must be addressed if the entire project is to be considered .successful.. Due to the known human response to blast effects and inherent dangers present in the use of explosives, the potential for the project being delayed or shutdown, or the blaster and associated company being named as a defendant in a lawsuit, is always a possibility. Therefore, the blast design and associated project bid must incorporate sound safety contingences and procedures that address those .what-if. Scenarios that may arise as a result of vibration, flyrock, public relations, and job-site personal safety.

Jan 1, 2002

This paper presents a brief discussion of three case histories to illustrate several aspects of the question of blasting in or immediately adjacent to concrete. The results demonstrate a need to make dramatic upward revisions in previous criteria, whether it be the standard particle velocity criteria or damage response spectra bounds, - especially those which include conservative upper limits of constant acceleration for the high-frequency portion of the spectrum. It is demonstrated, also, that conventional off-the-shelf blast-monitoring instruments are not capable of monitoring small blasts at close range. Both the frequencies and the levels of effect are beyond the range of such instruments. These case histories suggest further that there is a need to review the applicability of certain wellknown equations of elasticity.

Jan 1, 1980

By William McFerren, Pragasen Moodley

In contrast to global trends, African, especially South African, surface mining operations have shown a significant rate of adoption of Electronic Detonators (ED’s) over the last few years. Proven benefits of converting to ED’s from pyrotechnic initiation systems have aided this market conversion. These benefits are experienced throughout the mining operation. Benchmarking exercises, prior to the introduction of ED’s, form part of the conversion process and allow for quantifying improvements. Extensive work has been done on quantifying the benefits of converting to ED’s and have shown that results can be reproducible. Improvements have been experienced in many applications and include environmental impact control, improved mining efficiencies, increased cast benefit and improved size distribution. These step changes in blasting results, in conjunction with the adoption of ED technology have aided the rapid conversion of the African surface market.

Jan 1, 2004

By Tassilo Baur

Explosives are used in the entertainment industry in a wide variety of applications. Live performances such as automobile races, air shows and the like have incorporated the use of explosives into their programs. Even art work has been created employing explosive materials and techniques. The primary entertainment use of explosives, however, remains in motion pictures, television, theater and related fields where it comes under the auspices of special effects. Much of it falls roughly into the category of demolition, though the object being demolished may range from a cigarette in a person's mouth or clothing worn by actors to large objects such as automobiles, aircraft, or boats. This paper will attempt to provide an overview of the materials and methods by which these special effects are created as well as highlight the unique problems encountered in this field and their often equally unique solutions.

Jan 1, 1992

By Paul V. Sterk, James Wieser

Mining in underground situations requires constant change due to changing ore bodies and economics. The Homestake Mine in its 122 years of existence has gone through numerous changes due to these factors. Recent sustained low prices in gold and ore bodies that are smaller or within mined out areas have forced the mine to reevaluate how these ore blocks will be mined. This paper will describe the design, drilling, and blasting of a complex ore block using the blind raise uphole bulk mining method.

Jan 1, 1999

By Conny Sjoberg, Finn Ouchterlony, Bjorn Jonsson

This contribution reports an investigation of the blasting damage in the contour of an access ramp to a Swedish underground laboratory for nuclear waste related studies. Near zone vibration measurements were made for 7 rounds and the results converted to a site specific scaling law. A simple engineering correction for the influence of the charge length wee developed and the resulting equations used to predict the damage zone depths of three different drilling and charging patterns.

Jan 1, 1993

By John Manka

Emulsion manufactures often spot buy the diesel fuel used in their fuel phases from various sources. Because their diesel source changes, there can be large fuel variation which may affect the quality of the resulting emulsions. This paper shows that the diesel fuel used in manufacturing emulsion explosives has a significant impact on emulsion stability and that the fuel additives dosed into the diesel fuel as it is made also have an impact on the emulsion characteristics and stability. We found that fuels with higher distillation ranges improve emulsion stability. We also found that while none of the diesel fuel additives affected the initial formation of the emulsion, some fuel additives did affect the characteristics and stability of the emulsions as measured by emulsion viscosity, droplet size, high and low shear testing, bin storage testing and freeze thaw cycling.

Jan 1, 2002

By Jiang Han, J. F. Shao

Based on the rock blasting engineering, The Self-Organizing Map (SOM) network has been implemented for the concept and method of rock blastability classification. The Self-Organizing Map (SOM) is a neural network algorithm which is especially suitable for the analysis and visualization of high-dimensional data. It maps nonlinear statistical relationships between high-dimensional input data into simple geometric relationships, usually on a two-dimensional grid. The mapping roughly preserves the most important topological and metric relationships of the original data elements and, thus, inherently clusters the data. SOM allows easy data fusion enabling visualization and analysis of large databases of rock blasting engineering. As a case study, the classification technique based on SOM has been used to classify the rock mass blastability rank. It can be founded from this paper that the SOM networks can be developed well based on a comprehensive data set of rock blasting engineering.

Jan 1, 2002