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By Paul Muehl, Roger Lawrence

The massive sculpture taking place on Crazy Horse Mountain in the Black Hills of South Dakota, may Be the most unique application of precision blasting techniques in the world today, It is certainly the largest sculpture in history. And it is being carved not by the usual artist implements, but by engineering of explosives. This paper presents a review of the blastingasting techniques and challenges of blast earring the largest sculpture in the world,

Jan 1, 1991

By Gungor Tuncer, Erhan Bakirci, Ali Kahriman, Atilla Ozmen, O. Nuri Ucan, Savas Gorgun

There are several methods for demolition of structures but most of them depend mostly on conventional ways of using machines for breaking and crushing structural elements. However the need for lots of work force, expense and extreme amount of time for demolition, made most of these methods non-popular nowadays. Therefore, trials to accomplish a more economic and less time taking method lasted with the use of blasting. By applying controlled blasting on a suitable structure, the structure can collapse and break down to pieces in very short period of time, with no extra work force and cost. In spite of advantages of explosive demolition, the potential danger of explosives and the damage that the blasting may cause to surrondings, if not controlled properly, made people timid to the method especially in urban areas. Therefore, the pre-assumption by computational analysis has become an essential matter in the process.

Jan 1, 2002

By Steven Townend, Don Wadden

In today's global economy the need to stay competitive is essential for commercial survival and growth. To this end Inco is committed to continuous improvement in its operations. Various aspects of the mining process have been examined to find ways of improvement.

Jan 1, 1994

By Douglas R. Burns

Complying with SARA-Title III and the Emergency Planning and Community Right-To-Know Act as a Non-Manufacturing Facility. As of August 23, 1988 non-manufacturing facilities storing end using chemicals which require MSDS (Materia1 Safety Data Sheets) must fi1e with SERC (State Emergency Response Commission), the LEPC (Loca1 Emergency Planning Commission), and the loca1 Fire Department a list or copies of all MSDS sheets with the Tier I and Tier II forms completed.

Jan 1, 1989

By Jonathan Zimmerling, Rob Alkins

The model of waves emanating from a blast hole proposed by Heelan, and further developed by Blair and Minchinton, provides an approximation of particle motion in an isotropic, continuous and homogenous medium caused by a cylindrical pressure source. Previous work in the literature shows that the shapes of the peak strain and peak particle velocity contours generated by this model are influenced by priming location. This paper presents the results of experimental investigations into the effects of priming position in an explosive column and the resulting shape of the surrounding stress and particle velocity fields. Fifteen emulsion charges were detonated in a limestone quarry, of which eight were bottom primed and seven top primed. The charges were fully confined, with no breakout to any surface. Particle velocity was monitored using tri-axial sensors coupled to the rock using cement, and pressure sensors were placed in water filled boreholes for fourteen of the experiments. Statistically significant differences in peak pressure for bottom and top primed shots were observed. Blair and Minchinton developed two pressure source functions, one of which is scaled using the charge weight scaling law. New models of the explosive pressure source are developed and compared to those found in the literature. These models are directly calibrated by predicting the peak velocities achieved at the known locations of the velocity sensors, then minimizing the residual sum of squares between the predicted and observed peak vibration values. Due to the complexity of the model the residual sum of squares cannot be minimized using standard non-linear optimization techniques, so a stochastic, agent based global optimization method is employed. Models are then cross validated by comparing the relative predicted differences in stress between bottom and top priming position to the observed differences.

Jan 1, 2013

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 Bengt Niklasson

"A test stope at the Luossavaara Research Mine in Kiruna, Sweden,was divided into four different modules in which various hole patterns and explosives were tested in order to evaluate:1. The optimum combination of explosive and hole pattern2. The resulting fragmentation3. The damage to the surrounding rock4. The application techniques of the VCR mining method"

Jan 1, 1985

By Mike Zimmermann

With the steady decline in the production of dynamites throughout the world, a gap appeared in the market which could only be adequately filled by rigid paper packaged explosives. To fill this need, the Dri-Gel technology, which is the subject of this report, was developed.

Jan 1, 1998

By Ralph King

Blasting has been completed when the lawyer calls to say that a landowner has filed a suit alleging damages to the roof of his home. Mitigation talks fail to produce an adequate resolution and the case goes to court. The blaster has pictures of the area made after the blasting was done showing the good condition of the roof. However the judge fails to allow the photographs to be entered as evidence and the homeowner wins the case.

Jan 1, 2008

By Mauro Fornaro, Marilena Cardu, Renato Mancini

Detonating cord cutting is widespread in dimension stone extraction, especially in the case of hard, abrasive stones as granites, an important resource for Italian industry. General data on this production sector are briefly discussed and analyzed in the first part of the paper. The theoretical basis of operation are summarized, and compared to data obtained from selected commercial cases, in the second part.

Jan 1, 1994

By Lewis L. Oriard

Both theory and experience tell us that spatially distributed energy sources generate a more complex family of seismic waves than do point sources. The resulting effects in the near field (for close-in blasting) are significantly different than those from point sources although, at great distances from the source, the seismic waves take on many of the characteristics of point sources and can often be treated as such.

Jan 1, 1992

By David Davison, Richard Johnson

Metal-oxidant blends are ordinarily unsuitable as diiect replacements for explosives, because the reaction occurs too slowly. Oxide coatings protect metals, preventing or delaying reaction. By contrast, the electrically-activated reactive composites described below are configured as metal fibers or foils in close proximity to oxidants, with continuous electrical paths from one end to the other. By quickly vaporizing the metal component with an electrical pulse, a reactive composite will be activated, and the reaction will occur rapidly.

Jan 1, 1999

By J Paul Tidman, Stephen H. Chung

One of the requirements in open pit gold mines is to minimise the mixing of ore and waste. Dilution can be reduced by choke blasting and control of the initiating sequencing. The authors have used the DMC computer model (developed at SANDIA) to examine the effects of timing and charge distribution on ore dilution. The model has been calibrated by measurements of vertical uplift derived from high speed videos made at the Dome Super Pit in Timmins.

Jan 1, 1997

By Joseph A. Sohara, John J. Mullay, Curtis J. Keefer, Robert L. Schrepple

The desensitization of an explosive column by the action of a previous detonation (adjacent borehole, deck or detonating cord) is a vital concern to the explosives industry. Previous reports to this symposium and in other places have addressed this issue. However, this work has been mainly concerned with model or simulated conditions. No systematic study has appeared that utilizes an actual borehole environment. Thus the relation between this work and expected field performance is somewhat uncertain. The present paper attempts to partially resolve this difficulty.

Jan 1, 1990

By Raymond M. Dixon, Dale L. Ramsey

Upon being introduced to the MAGNETIC COUPLING concept,Balsinger,Inc. wanted to conduct field trials to explore the potential of Magnetic Coupling in the U.S.. Although the Magnetic Coupling Concept has been widely used, the U.S. proposed blasting criterion not previously addressed by the system. Modification to the system assembly and blasting accessories had to be made to make the system adaptable to our specific requirements. The field trials and system modifications are the basis of this paper.

Jan 1, 1990

By Edward J. Walter

A vibration record is a complex of motions resulting from a combination of direct, reflected and refracted seismic energy that originated at a blast source. Multiple hole blasting using delays further complicates the motion in that overlapping of seismic wave trains may occur when delays do not fire in the programed sequence. This can result in variations in amplitude, frequency and wave-1ength of the vibration. Amplitude may be doubled, frequency may oscillate between the highest and lowest frequencies present and wave-length may approach doubling of the longest wave-length present. These effects can present serious problems to conducting a safe blasting program since increased amplitudes and lower frequencies present higher damage potentials for structures. The development of these effects is described and illustrated graphically to show how these effects can occur.

Jan 1, 1989

By Kunihisa Katsuyama, Yuji Ogata, Takuya Taguchi, Toshinori Arikiri, Yuji Wada, Kiyoshi Hashizume

The impact sensitivity of hot emulsion matrices was examined to investigate the safety assessment in the emulsifying equipment which forms the emulsion matrix in a water-in-oil type emulsion explosive. The sensitivity could not be evaluated by the small fallhammer test device commonly used in Japan. Therefore, a large fallhammer test device was used. It was confirmed that an explosion, a decomposition, or a no-reaction took place according to the degree of the impact. When a decomposition took place in the hot emulsion matrix, the behavior of it was investigated further by a DDT test. It was found that a decomposition, or a no-reaction occurred according to the degree of confinement.

Jan 1, 1997

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 Robert Lee, Jay Rodgers, Kirk Whitaker

The time domain during which an explosive detonates and causes rock to fragment and displace is on the order of tens of milliseconds. Because of this, the dynamic processes that occur during this time frame often become a source of confusion when trying to analyze the performance of explosive products in decked blast designs. As an illustration, the authors have experimentally examined explosives malfunction in decked blasts through state-of-the-art measurement techniques. The interaction of explosive products and blast geometry was examined in detail using the analysis of a series of decked blastholes. Explosive and initiator malfunction in decked blasts is often considered to be entirely the result of insufficient inert decking material, however, it is shown that rock properties and dynamic burden conditions may have a significant impact on decking performance. The successful application of deck-blasting technique for control of ground vibration amplitude relies on an understanding of the true dynamic performance of the blasthole.

Jan 1, 2000

By J. Esterle, J. Kruttschnitt

Fragmentation modelling in soft rocks presents a challenge due to their propensity to further fragment after blasting during normal handling. Coal and some iron ore deposits are examples of materials that undergo significant degradation during the extraction, hauling and dumping process of the mining operation. The Kuz-Ram model is an empirically derived predictor of size distribution from blasting hard rock. Little breakage occurs during excavation and subsequent sizing of hard rock, so the measured Run of Mine (ROM) size distribution is essentially the same as the post-blast (before excavation) size distribution. However, for soft rocks, each step of the excavation and hauling operation imparts energy to the rock particles so the measured. ROM size distribution will be significantly different from the postblast size distribution. In order to calculate the ROM fragmentation at any stage of the extraction (or sizing) operation, the JKMRC has developed a model that combines both blast fragmentation and degradation through subsequent handling.

Jan 1, 2001