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By Steve Dillingham

Today, a typical blaster is likely to wear many hats, including, but not limited to, supervisor, risk manager, safety coordinator, explosives engineer, communicator, as well as professional decision maker. Simply put, a blaster in the new millennium is an all encompassing blast site manager. As you know, accidents on the blast site can range from blast crew injuries to blasting incidents resulting from vibration, flyrock, misfires, etc. Not surprising, the incidents can quite often be traced back to direct preventable human action on the blast site. They can, however, frequently be avoided, if responsibly identified early and managed properly by an efficient blast site manager. Your company cannot afford to simply employ blasters; good blast site managers are necessary to produce the safest results possible.

Jan 1, 2001

By M. Hagfors

Underwater explosions have been used several decades for the determination energy content of explosives. It’s the only test method by which shock and gas heave energy values can be determined separately. The total energy is a sum of these two partial energies. This test method enables us to develop explosives for different purposes; the military high explosives should contain more shock energy whereas the gas heave energy is a very important feature for the blasting explosives. The method also enables us to observe the changes and to adjust the energy content of an explosive as a function of increments of one or more energetic component.

Jan 1, 2006

By Larry: McAnuff Schneider, Edward Walter, Gordon Shaw, Daniel Grieco, Dennis Clark

During the 1998 Annual Conference of the International Society of Explosives Engineers (ISEE), the Seismograph Section established a subcommittee for the purpose of compiling a list of all regulations pertaining to limits imposed on ground vibration generated by blasting. The goal of this project was to determine the vibration regulatory levels being enforced, with the further intention of examining their scope, and uniformity. A secondary purpose was to evaluate the consistency of the existing regulations with the current scientific findings on structural response and damage potential.

Jan 1, 2001

By Stig O. Olofsson

The problem of overbreak in underground construction and mining is normally approached by a variety of smooth blasting methods. Numerous small diameter, low velocity explosives have been developed specifically for blasting the contour line. Increased mechanization in rock excavation has led to the development of several methods of mechanical explosive loading. A new mechanically loaded smooth blasting explosive was developed in Sweden . However, several limitations were realised, which after several trials resulted in a hybrid smooth blasting method, The Suaer Cautious Contour Blasting Method which will be discussed in this paper.

Jan 1, 1994

By Richard Goodridge, Stephen Thomsqn, S Rodgers, D Tunaley

The mining, quarry and construction industries are facing’new challenges everyday. These challenges can be imposed by economic objectives or through external factors such as extreme geological conditions. Simultaneously, all mines, quarries and construction sites are facing more and more stringent environmental requirements.

Jan 1, 1998

By Martti Hagfors

Underwater explosions have been used as a test method for the determination of energy content of explosives for several decades. This is the only test method by which shock, gas heave and total energy values can be measured separately. The experimental data can be measured from the pressure-time curves measured by the pressure-recording unit. The shock energy is integrated from the shock peak area and the gas heave energy is calculated from the time interval between the primary shock wave front and the shock wave caused by the first bubble implosion. tb. Bubble period, tb, is the time of first bubble oscillation, the time which passes after the shock peak front to the first bubble peak. The total energy value is the sum of these two partial energies.

Jan 1, 2009

By Fumihiko Sumiya, Hideki Hamashima, Shigeru Itoh, Shinya Tanaka

The detonation characteristics of non-ideal explosives, especially the emulsion explosives, are critically affected by the confinement of case. In this study, we focused the shock wave propagating in case as confinement factor. Therefore, the objective of this study was to obtain a better understanding of the influence of shock wave propagating in case on the detonation characteristics of explosives in laboratory scale.

Jan 1, 2007

By Dennis E. Mitchell

The need to develop and field explosive, pyrotechnic and propellant initiating systems that have high reliability and extraordinary safety requirements has led to the exploration and development of several materials and initiation systems at our laboratories. Our approach to initiating device development encompasses five main areas; energetic materials development , device physics, theoretical analysis and model development and experimental verifications

Jan 1, 1995

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 Craig Wilbour, John Stimberis, Rob Gibson, Lee Redden

An avalanche is a snow slide. A simple explanation is that the snow on a slope will slide (avalanche) when the snow strength can no longer support its own weight. Snow avalanches happen when the load from snowfall or ram on a snow slope increases faster than the stre n g t h of the bonds between snow crystals. Avalanches can also happen when the strength of a buried layer decre a s e s . Active avalanche control is the intentional triggering of slides. Washington State Department of Tr a n s p o r t a t i o n (WSDOT), does avalanche control to minimize the chance of natural avalanches into traffic. Avalanche control work is done all over the world by: highway departments, ski resorts, railroads, mining operations, utility companies, and other activities threatened by avalanches. The majority of active avalanche control is done with skis, by explosives, or exploding projectiles. Blasting techniques and practices have evolved to fit the specific needs of avalanche contro l . Passive avalanche control is the use of engineered s t r u c t u res such as snow sheds, bridges, or snow supporting devices, to permanently protect a specific location from avalanches. The problem is that these struct u res are extremely expensive. There are a variety of passive avalanche control measures as well as the active m e a s u res used to protect the highway over Snoqualmie Pass. As traffic volume and use expectations incre a s e , m o re extensive passive measures will be needed to keep avalanches from affecting the highway.

Jan 1, 2004

By Earl C. Hutchison, Wade C. Hutchison

T 0 effectively evaluate property damage that is claimed to have been caused by blasting activities and in order to lay the proper foundation to build the best legal defense, identification of the actual causation for the damages are necessary. For the past twenty years, engineering personnel from VCE, Inc. (previously Vibration Control Engineering, Inc.) have been evaluating claimed blasting damages with pre- and postblast inspections, with analysis of seismic levels, blasting amounts at given distances, and with other engineering considerations. In addition to these evaluations, they have also documented other causes for damages which are of the types that are often claimed as blasting damage.

Jan 1, 1995

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

By S. J. Dillingham

As we enter the new century and close out the old, it has become standard procedure for most blasters to complete a blasting log or shot report following a blast. However, how can you be sure these completed blasting logs are worth the paper or electronic space they occupy.3 Is the recorded data accurate and meaningful? Will the blasting logs stand up under investigation? This paper will attempt to define the purpose of a blasting log, illustrate common mistakes, discuss potential problems, and indicate steps that a company or individual blaster can take to improve and protect against costly errors. The end result will be a reminder of the importance of accurate documentation following a blast that must be given the same individual effort as went into the blasting itself. This paper will also attempt to achieve a proactive training resource to improve the use of blasting logs. A completed blasting log is, quite possibly, the only witness to the overall credibility of the work of the responsible blaster. The log may remain perpetually silent, only to end up in a file that is moved progressively with time to various levels of long-term storage. But, will this silent witness be ready to speak out should a concern arise from the blasting ? Will the blasting log communicate with authority and credibility, or will it be ridiculed by investigation and silenced in shame with costly adverse results for the blaster and company? It is not enough to simply complete a blasting log. The information it contains must be accurate enough to stand the test of time and arduous scrutiny. Unfortunately, most blasters and their associated blasting companies do not realize the status of the silent witness until it is too late.

Jan 1, 2000

By Teele Tuuna, Voglers Eesti OÜ

Blasting operations are a strong and important part in any kind of building and mining industry, a shot-firer profession is one of the oldest professions in the civilized world. It still serves an important and ongoing purpose in the modern economy all over the world. Europe, nowadays, values strongly the mobility of workers, the movement of know-how and labor force between different countries inside Europe. There are no borders for most of the everyday professions.

Jan 1, 2018

By Brian Gar Wingfield

"The introduction of the QuarryMan laser profile system in 1987, along with the development of the corresponding 3-D software, gave a qualified operator pertinent information about dimensions of quarry highwalls, pattern and hole loading design, stockpile profiles, etc . . . Attributes helpful for this endeavor included surveying, computer, and blasting knowledge. Since not all operators had theseskills, a simpler model, the QuarryAce, was designed to look a t highwall dimensions in 2-D view . Al though less sophisticated than the QuarryMan instrument and its software, it is simpler to instruct in its use and has the ability to determine burdens at different depth levels . An in-house user f r i e n d l y computer program was designed to utilize QuarryAce depth vs. burden data . This program was created to enable laser and computer novices to generate information useful to the everyday blaster."

Jan 1, 1992

By A B. Opperman

For many years explosives energy has been utilized in mining and construction as well as many other applications which are vital to our way of life. Many types of explosives have made their contribution as technology has moved forward. One of the best known was dynamite, which for many years was the mainstay of explosives users. Although dynamite had many advantages over its predecessors, it had the principal shortcomings of being somewhat hazardous to handle and was known as a headache producer.

Jan 1, 1975

By J Deen, P Sterk, W Forsyth

Homestake Mining Company has made a firm commitment to develop a functional and cost effective perimeter blasting program. The goal of the program is to develop smooth, sound walls in all development ends. A good perimeter blasting method will improve safety, reduce waste rock handling, allow easier support installation and reduce scaling time. All the benefits will contribute to an overall reduction in total development costs.

Jan 1, 1997

By Robert B. Hopler

Explosives, originally used only in fireworks and warfare, became legitimate contributors to human progress when miners in Eastern Europe began using them to break rock in the early 1600%. Since that time these powerful materials have had a dual role in the world: as agents of destruction in war, and as irreplaceable tools necessary to advance civilization. In the latter role, they serve as agents to enable mankind to produce metals, build roads, and drive tunnels. In other words, to provide those materials, services, and infrastructure without which the modern world could not exist.

Jan 1, 1997

By David Harrison, Edward J. Walter, Meitra Ferek

Agreat tool in the prevention of blasting complaints and subsequent damage claims. In today’s highly competitive industry, we are always looking for ways to become more cost effective. This article investigates the importance of pre-blast surveys-not just for regulatory compliance, but as an overall long term cost cutting and public relations tool.

Jan 1, 1995

By Sushil Bhandari, S. S. Rathore

Controlled drilling and blasting continue to be an important method of block production and for block splitting. Drill and blast technique has disadvantage that sometimes, it produces cracks in uncontrolled manner and also produces micro cracks in the block as well as in remaining rock, if not carefully carried out. Recovery by this method is low compared to other methods. Therefore, attempts have continued to develop controlled growth of crack in desired direction. In this paper a series of tests are described using detonating fuse in marble. Economics of different methods is also compared. In comparison to conventional use when holes are lined with inexpensive cardboard or plastic liners with a slit, the cost and damage is the least and development of crack is in desired direction.

Jan 1, 2002