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By C W. "Mickey" Bradley

Thunder strikes terror in the hearts of man and has since the advent of time. We all fear the unknown; even the Greeks created a god, THOR, to be responsible for the thunder and rain. Thunder, by itself, can't hurt anyone; it is simply hot air moving very fast. Thunder, however, is caused by lightning and lightning is what we need to fear and rightfully so. Annually, lightning kills hundreds of Americans, injures another 2,000, damages or destroys approximately 30,000 structures, 1 starts thousands of forest fires and strikes mine properties over 100,000 times.

Jan 1, 1992

By Richard Curtis

Optimum Colliery is presently experiencing a shortfall of stripping capacity in order to meet its production requirements. Due to the long dragline procurement times, several alternative stripping methods were evaluated in order to alleviate this shortfall in the interim period. Based on the experience gained at the mine. The writer will discuss some of the important factors which influence dragline performance and show how these factors may by used in a theoretical approach to analyse various dragline applications.

Jan 1, 1990

By Gary Kahn

In this document the VODR is discussed from a technical point of view and is intended to give the reader a feel for the design of the instrument, its technical specifications, and its limitations. It is not intended as a tutorial on the use of the instrument in the field.

Jan 1, 1989

By Jack Eloranta

Optimization of blasting requires the comprehension of processes including drilling through milling. The author has previously considered the role of powder factor in relationship to downstream processing costs. Recent modeling done by Lownds provides improved prediction of fragmentation based on the distribution and level of blast energy. Many recent studies have indicated improved downstream costs due to higher powder factor. However, changes in powder factor are accompanied by changes in pattern. The purpose is to segregate the effects of higher powder factor from powder distribution. This paper will attempt to use typical Mesabi Range iron ore parameters and costs to illuminate the subject of total process optimization.

Jan 1, 2001

By Fred Drury

I spent 38 years in the Industry in a variety of sales, technical and management positions. I started out with Hercules, then was one of the founders of ECONEX, a large regional Distributor, and finally served with Dyno Nobel as a global Vice President, based in Oslo, Norway. When I retired in the fall of 1998, I looked forward to spending a lot less time traveling and a lot more time around home. After 4 years, I’m still traveling and still wondering how to find a few more hours in the day.

Jan 1, 2003

The common approach of designing blasts on a trial and error basis is quickly coming to an end. When utilizing the full scale blast environment, trial and error can quickly become cost prohibitive and leaves much to be desired in terms of true blast diagnostics. In these situations testing is usually only continued until a perceived improvement is achieved and when the gross undesirables in blast results are removed. This does not preclude, however, that further improvements of up to 100% or more can not be obtained.

Jan 1, 1994

By Detnet Solutions

1. “Daisy-Chain” concept The term “daisy-chain” stems from the fact that when the HotShot? detonators are connected there is a chain or electrical path for electrical current to flow from detonator A to detonator B, detonator B to detonator C etc until the path is terminated by an electrical means. The “daisy-chain” concept has long been used in electronic detonator systems, historically used in Expert Explosives’ ExEx 1000 5/6 wire system and currently in use in African Explosives Limited (AEL’s) Electrodet? electronic detonator system and has been adopted as the basis upon which the “auto-programmability” of the HotShot? electronic detonator system functions. HotShot? Detonators are connected to each other in a string, completing a “daisy chain”, and during the auto-detection mode of the control equipment, it is possible for the equipment to determine the order of hookup of the detonators as well as map the entire blast layout. The auxiliary components (Row Controllers & Branch Controllers) assist the control equipment in mapping the entire blast by indicating different points on the blast, i.e. The inflection point of a row of blast holes on a closed chevron timing pattern, the beginning of row of blast holes on open chevron timing pattern and extra blast holes or extra blast rows.

Jan 1, 2004

By Rachel Bernau

Water wells, aquifers, and pipelines rarely incur damage from nearby blast vibrations. Extensive ground vibrations may cause a drop in the water table thereby changing an aquifer’s structure or drying up a well. Studies on the reactions of aquifers and water wells have been performed in Montana, North Dakota, and the Appalachia Coal Region. All of these studies reported that vibrations did not change the properties of the monitored aquifers and water wells. Rather, evidence suggests that any incurred damage was caused by block motion and downsloping.

Jan 1, 2001

By D T. Froedge

With successive generations of the Iso-Seismic System, we are acquiring more and more information about the actual behavior of blast induced ground, and airborne vibration, as it propagates through the environment. Some of the original “truths” that have been long accepted may have to be \revised.

Jan 1, 1995

By Lee B. Paterson

Mining Engineers throughout the world have an appreciation for the importance of the role of the Blasthole Drill in one of the primary elements of the mining process. This paper highlights areas that could influence the overall cost effectiveness of that process of breaking rock and the associated downstream mining and ore recovery activities - and how the drill is designed and configured to meet that challenge. Factors influencing drill productivity and overall cost effectiveness are addressed, particularly regarding the benefits which are not necessarily reflected in the drilling process and therefore more difficult to quantify. This paper explores some of the downstream benefits of what we do to the drilling process.

Jan 1, 2000

By Thomas C. Palangio

Since the advent of explosives, people have been trying to mechanize the process of loading it into long, narrow holes. Automated loading frees manpower from the arduous task of charging granular, cartridged and slurry explosives. An unexpected bonus of the automation process has been the realization of some valuable side effects such as high throughputs which speed up the loading process and higher loading densities which enhance explosive performance and permit hole patterns to be expanded.

Jan 1, 1990

By Donald H. Matthews

I wish to preface my remarks with the warning that I, in no way profess to be an authority on the U. S. Department of Transportation, Hazardous Materials Regulations, 49CFR Parts 100-199, nor attempt to advise any one on the regulations or how they should conduct their business in relation to the regulations. I merely wish to convey my interpretations of the regulations and some of the procedures adopted by my company to comply with these regulations, with the hope that this information may help others to better understand the regulations and help them formulate their own procedures for compliance. I will cover nine problem areas and furnish sources of information for anyone concerned with explosives transportation.

Jan 1, 1977

By Viktor Aranovich, Thomas E. Brown

The Almalyk Integrated Mining and Metallurgical Plant is located near Tashkant in Uzbekistan and is one of the former Soviet Union's largest copper producers. Almalyk consumes about 10,000 metric tonnes of explosives annually and expects this requirement to double by the end of the century as they implement a program to boost mine output.

Jan 1, 1998

By Larry Schneider

"0 ne of the incentives that led to the development of non-electric shock tube initiation systems was the desire within the industry to improve detonator safety. And to the extent that nonelectric initiators are immune to the hazards of stray current and radio frequency energy found on normal blast sites, an advancement in safety has been accomplished. However, as a cautionary note, it is important to realize that there are still many hazards associated with any initiation system. While some of these hazards may differ from those associated with electric detonators, others are identical to those associated with any type of initiation system. For instance, contrary to what some uninformedblasters may believe, lightning remains a hazard when using nonelectric initiation as well as electric initiation."

Jan 1, 1995

By H. Rossmanith

This contribution introduces the fundamental concepts of wave propagation and fracture mechanics which form the basis of electronic blasting, i.e. precise initiation timing using electronic detonators. The concept of Lagrange diagrams will be frequently used for the calculation of the delay time between blast-holes in a row and rows of blast-holes. The effect of burden and structural geology will be briefly touched. It is found that the advanced blasting technology based on the use of electronic detonators introduces a change of paradigm. It will be shown that knowledge in wave propagation and fracture mechanics is essential for the successful application of the new blasting technique in industry. In particular, the delay time, the wave speeds in the rock mass, the shape of the wave pulse and the acoustic impedance mismatch have become decisive parameters in advanced blasting. Utilizing the wave speed and wave shapes of detonations, large scale tests Utilizing the wave speed and wave shapes of detonations, large scale tests in various countries (Australia, Chile, etc.) have shown that optimal delay timing requires shorter delay times in conjunction with allowing for a wider drilling pattern and the use of a reduced amount of explosives, i.e. a lower powder factor. This seemingly contradictory arrangement is fully justified by using scientific principles in blasting, and converting blasting from an art to a scientific discipline.

Jan 1, 2003

By Kyle Apple

The following is a case study of how LuckStone Corporation improved their blast monitoring and documentation program. A number of resources already at their disposal have been utilized to improve the body of data collected from each blast. The tools being used include GPS, aerial photos, and a user-friendly push button format excel spreadsheet. The data collected include product by product records of materials used, distances to all concerned neighbors, seismograph data, etc: The spreadsheet has been designed to perform an ongoing analysis of blasting trends. The program has been carried out at a corporate level and is in use by blasters at each location. This paper addresses the advantages and drawbacks of this program. It also addresses the ways in which the various tools were integrated, Discussed as well is the need for simplicity when bringing “new” technology to the field and the steps taken in familiarizing the end user to changes.

Jan 1, 2001

By Kate Satish

M/s Konkan Railways Corporation are constructing 760 kms long rail road in the Western Coastal Region of India. The rail road encounters 75 tunnels through the Western Ghats of India with a total length of 78.35 kms, the longest tunnel being 6.5 kms long. The tunnels are of horse shoes shape having a cross section of about 37 Sq.meters

Jan 1, 1996

By Stacy Loizeaux

The Beirut Hilton Hotel, which was built in 1975, but never occupied, was imploded on Sunday, July 14, 2002 by Controlled Demolition, Inc. (CDI) of Phoenix, Maryland and their client, Optimal Engineering Consulting & Contracting, SARL, (OECC) of Antelias, Lebanon to make room for a new hotel. Twenty-seven years ago, just days before the grand opening, the Hilton Hotel became the site of fighting in Lebanon’s Civil War. Christian and Muslim militiamen fought room to room for control of the building and other nearby hotels. The Hilton, two other major hotels and other high-rise buildings were ravaged by the fighting. The building was one of the three major hotels badly damaged, but not rebuilt, in Lebanon. Located in the City Center, the Hilton stood out in a major redevelopment area which, in recent years, had erased the scars of the 15 year long Civil Wa r.

Jan 1, 2003

By Ivan Carrasco, Benjamin Cebrian

Mining companies have traditionally organized their structure around a scheme easy to manage: Mining Department and Mill Department. In a challenging landscape for mining, with decreasing grades, increasing rock hardness and more expensive energy, this way to organize departments has resulted in internal disputes and often contradictory targets between both mine and mill. These compete for individual, separated budgets whose Key Performance Indexes often damage each other’s output. The results are increased total production costs and reduction of profits. Some companies have completed the first step in eliminating these inefficiencies by creating Fragmentation Engineers and Fragmentation Superintendents. With all the knowledge available on the overall fragmentation process and costs, in this document an overhaul of the traditional management structure is proposed. Is a step further Mine-to-mill and mine-to-leach programs. Since comminution is the most expensive step of the mineral exploitation, it should be taken as a whole, not divided into competing departments. Thus, mining departments should be re-grouped into: transportation, fragmentation and flotation.

Jan 1, 2014

By M. Ramulu, A. Raina, A. Chakraborty, Jethwa Choudhury, Dudhankar

Application of digital image analysis technique for assessment of blast fragmentation is gaining grounds in India, very recently. Central Mining Research Institute, India made its maiden attempt to optimize blast design based on fragmentation assessment of one of the biggest opencast mines of Singareni Collieries Company Limited, India. Indigenously developed photoanalysis software called ‘FRAGALYST’ was used for measurement of blast fragmentation A series of trial blasts were carried out in overburden benches with ongoing blast parameters and pictures of muck pile were taken by video camera for image analysis. Cycle time study of loaders and dumpers was done to determine machinery performance for each and every blast. Optimization of pre-blast parameters like specific charge, specific drilling and post-blast results like shovel cycle time and dumper cycle time, was done to determine optimum range of fragmentation. Interpreting the mean fragment size (K50) obtained by image analysis the blast design parameters were modified.

Jan 1, 2001