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By Keith L. Bockelman

The Colowyo mine is a unique surface coal mining operation because it is a multiple seam pit. Using a combination of a shovel-truck and dragline operation, Colowyo mines 8 seams of coal to a depth of 400 ft. Over the past 3 years a number of operational changes have occurred, one of which is the implementation of blast casting. Through this implementation Colowyo has been able to eliminate over one million cubic yards a year, which would have had to be removed by the shovel-truck operation. This has also brought about a significant decrease in the stripping cost per ton within the dragline operation.

Jan 1, 1985

By Dennis Alan Clark

An increase in construction and quarry operations has necessitated blasting activities in areas once considered rural and in the close proximity of transmission pipelines. A method to determine the maximum allowable bending stress by the formulas outlined by the Battelle Memorial Institute report of October, 1962, and the assumed stress comparison with actual measured data is presented. A direct relationship between pipe stress and ground particle velocity is shown, and a method to predict stress by relating stress to charge weight and distance from the shot point is discussed.

Jan 1, 1976

By Wang Hao

"Demolition of reinforced concrete frame structures in building crowded cities is a hardproblem in control blasting. Any mistakes, e.g. wrong toppling direction of multi-storeybuilding or incompleted blasting of structures will all cause terrible accidents.To demolishframe structures safely, various disciplines including structural mechanics, explosionmechanics, rock engineering, etc. are involved"

Jan 1, 1993

By Zhang Zhenyu, Wu Xinxia

The blasting quarrying technology of rock material of rock-fill dam is one of the more complex problems in the field of engineering blasting at present. The Kuz-Ram model is not suited to predict fragmentation distribution under the geology condition of Tianshengqiao(TSQ) fist-step power station. The modification of kuz-Ram model is discussed. With reference to the idea of model establishment of Kuz-Ram model and according to the results of experimental blasting in-situ, two fragmentation prediction models-TSQ-1 and TSQ-2 model are presented which are adapted to the particular condition of rock material querying blasting of rock-fill dam with concrete facing of TSQ first-step power station. The rapid judgment method of qualified grade material and the method of optimizing blasting parameters are also presented in this paper.

Jan 1, 1998

By Jack Eloranta

This paper compares energy requirements for blasting, crushing and grinding. By tracking electrical consumption for various powder factors, a general trend has appeared. This study involves over 100 million tons of ore and powder factors ranging from .5 lbs/LT to .8 lbs/LT. Actual energy usage is compared to predicted energy based on the Bond equation.

Jan 1, 1997

By J R. Brinkmann, S G. Giltner

Nearly all of the South African gold mining industry still uses fuse and igniter-cord initiation systems. Over the past 30 years numerous attempts at developing new initiation systems have not yielded a viable alternative. New initiation systems for narrow stopes are currently being developed by various concerns and the likelihood of these efforts producing feasible alternatives is greatly improved due to the recent advances in electronics technology. The greatest potential benefit of alternative initiation systems is increased production rates through improvements in accuracy and reliability of firing over that of fuse/igniter-cord. Another important feature is the capability of millisecond delay firing as this can lead to reduced stope cleaning times by way of enhanced rock throw and improved fragmentation characteristics.

Jan 1, 1989

It is a case study of huge rock-mass, loosened out from the parent rock-body, & posing a potential danger to structures down below the slope on which this rock mass was standing. Case was dealt in two phases, by tying/stitching the rock mass to the parent rockbody and breaking it using controlled blasting technique.

Jan 1, 1997

By Dennis A. Clark, Richard E. Calvin

As the scarcity of mineral resources increase and subsurface mining activities expand along with simultaneous surface mining in coal, industrial minerals and rocks, along with metals, the need to insure safe conditions is paramount.

Jan 1, 1981

By G Alan Foster

The presence of approximately 600,000 attorneys in the U.S.A. and the determination by the courts that blasting is considered an 'ultra hazardous' activity makes every practical blaster aware that at some time during his working life he will probably be faced with defending himself in court.

Jan 1, 1982

By TH Kleine, AR Cameron

Size assessment of fragmentation is all about estimating the population of fragment sizes in the rock pile. A knowledge of the size distribution of particles can be used in applications from evaluating the stability of a waste dump, to optimizing a blast design to achieve a required fragmentation, to on-line control of a crushing and sieving operation.

Jan 1, 1997

By David Leidel

A major characteristic that distinguishes modern society from its predecessors is the understanding that events are not driven by the whims of the gods, pre-ordained fate or nature, but are controlled to a greater or lesser extent by the actions, (or inactions), of people. The study of risk assessment is the basis for determining risk or the likelihood of an event occurring combined with the consequences of that event if it does occur. This study is indubitably linked to the mathematics of probability and statistics which permits the quantification of risk. As the Industrial Revolution significantly increased the exposure of persons to new types of energy sources, materials, equipment, and means of more rapid transportation of goods and people, quantitative risk assessment became a vital tool in protecting workers and the general public exposed to these new technologies.

Jan 1, 2007

By R M. Bhatawdekar, A I. Theresraj, H S. Venkatesh

Wadi Limestone Quarry is one of the largest captive mines of Associated Cement Companies Ltd, India. The mine management wanted to extend the excavation as close to the plant as possible for maximum exploitation of the deposit. The National Institute of Rock Mechanics and the management of Wadi Limestone Quarry carried out comprehensive investigations to evolve a methodology to control vibration and flyrock within safe limits.

Jan 1, 1999

By Patricia Mendoza Watson, Lundquist Robert G

The velocity with which the burden moves after blasting is of concern for safety and economic reasons. Models developed for motion velocity by various researchers were reviewed and likely model parameters were used to develop statistically significant models. Regression analysis and residual analysis were used to determine the model coefficients and the accuracy of the models.

Jan 1, 1990

By Charles A. Kliche

The Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) established a national program for responding to releases of hazardous substances into the environment. The funding mechanism for this program is the Hazardous Substance Response Trust Fund (commonly referred to as Superfund), which provides funding for the implementation of removal and remedial response actions.

Jan 1, 1997

By Carl Hendricks

AQUILA Mining Systems Ltd. is the world leader in drill monitoring, control and GPS based drill navigation systems for the mining industry. This paper will review the general design and application of AQUILA.s drill systems currently in use throughout the world and the key benefits that derive through their use.

Jan 1, 2002

By Robert Hopler

In part one we discussed a Chinese seismoscope allegedly invented and used in the year 136 (or 132, depending on the source). Interestingly, historical references to the measurement of earth movements then seem to be nonexistent until up into the 1700’s. There could be two explanations for this hiatus: first, that there were no earthquakes in the world for 1600 years, or, second, the “Dark Ages” really did exist, where intellectual inquiry and all sorts of learning came to a halt. Of course there were earthquakes, so the explanation for the lack of a record of invention is the reality of the Dark Ages. explained is the fact that the Dark Ages ended in about A.D. 1000, but that is beyond the scope of this story.

Jan 1, 2006

By D T. Froedge

To preface these remarks, it is not intended that this paper be a criticism of anyone or any organization involved in drafting the current regulations, for it appears that everyone involved in the process has made an extreme effort to be safe. We wish to show that in this case by making huge safety margins, we have created an unsafe condition in another area. That is by creating vast safety margins in the area of mobile transmitter intensity versus distance scales we have caused a severe handicap in the use of the mobile transmitter in securing blasting areas. The use of these mobile transmitters, which are absolutely essential in clearing areas where there are woods, mountains, or urban structures is virtually eliminated because of the safety factors prescribed in the regulations. We wish to show that these mobile transmitter safety factors are much too great, and can be traded off to increase the margin of safety in the ability to clear blasting areas.

Jan 1, 1975

By A B. Jr Nunn, W C. Gould

Good community relations is a major concern at this central Virginia aggregate quarry. In this paper, the authors describe the use of a new electric millisecond delay initiation system that has reduced the average level of vibration by 27% since its use began in late 1984.

Jan 1, 1986

By John C. Brulia

PowerAN is a tradename of Atlas Powder Company for a new line of explosive products comprising blends of emulsion and ANFO in a variety of bulk and packaged grades. The bulk PowerAN grades are either augered or pumped depending upon emulsion content. Augered PowerAN blends contain up to 60% emulsion. Pumped PowerAN grades have an emulsion content of 75% or higher. The blending of PowerAN is usually accomplished at the borehole to satisfy specific borehole conditions. Packaged PowerAN grades are produced in several types of mix plants in diameters of 4" and greater. PowerAN 300 (30% emulsion) and PowerAN 500 (50% emulsion) are the two most popular grades and their chief application is as an economical, high energy replacement for ANFO HD in wet holes. PowerAN combines the cost effectiveness of ANFO with the high performance of emulsions, permitting the blasting engineer to strike an optimum balance between drill pattern expansion and increased productivity according to need.

Jan 1, 1985

By Thomas Palangio, Lyall Workman, Jack Eloranta, Tom C. Palangio

The fragmentation distribution of the blasted ore is an important descriptor of blasting results. Traditionally it has been hard to measure quantitatively. Developments in image analysis over several years makes it more feasible to measure fragmentation before crushing on a continuous basis. Post crushing, mill feed distributions can also be measured.

Jan 1, 2007