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By A Brodbeck, AT Spathis

Australian regulatory control of ground vibration and airblast arising from mining, quarrying and civil construction operations is spread across a number of federal, state and local authorities and across a number of departments with various jurisdictions. The Australian Standard AS 2187.2 contains an informative appendix on damage-related criteria and it is the primary reference for the regulators. The complete standard and the informative appendix is currently undergoing major revision with a focus for the latter on implementing frequency-dependent criteria for ground vibration. Certain directions for change have been raised for consideration by the standing committee, ranging from fundamental issues of measurement and interpretation and others that overlap human comfort criteria. It is anticipated that some of the suggestions will eventually make their way into future standards after an adequate period of consultation and consideration by both the Australian public and others involved in the associated industries.

Jan 1, 2005

By N. Powell, P. Hunt, A. Wetherelt

This paper considers the current methods of analysis employed, the validity of assumptions made and the reliability of results and predictions derived; where appropriate, alternative methods are proposed which are more accurate and can be applied with greater confidence. In regard to data collection, new local blasting data has been analysed and conclusions drawn but, due to the restricted amount of space available, reference to data set A only has been made in the text. The problem of mathematical model choice is considered and results for two and three parameter power laws are compared. The very important matter of parameter determination is discussed fully, with major emphasis being placed on the comparative merits of log-log linear, log-log planar and direct power law regression. Supporting data analysis examples are included. Assumptions regarding the normality of ‘best-fit’ regression model residual distributions are questioned and the reliability of associated safety limit determinations is discussed.

Jan 1, 2003

By Steve Dillingham

There are some blasters and blasting companies that just seem to have better safety reputations than others. This is in spite of the fact that they are essentially doing the same type of work under similar conditions. To achieve that enviable safety reputation, it simply comes down to a strong safety culture prompted by a responsibility for others, as well as yourself and your company.

Jan 1, 2003

By Douglas A. Bartley, Davey Bickford, Raphael Trousselle

The long awaited arrival of a high accuracy detonator to reach the explosives end user will provide new opportunities the blasting community to become better equipped and able to improve upon the current approaches and methodologies used in blast design as they apply to the mitigation of adverse effects from blasting. This paper will detail the approach and findings throughout a several month research project to quantify the high accuracy detonator benefits and to mitigate a long standing vibration problem at a hard rock stone quarry in the state of New York. The tests conducted in this study were designed to provide important information as to the relationship between the use of high accuracy detonators and overall blast performance in terms of ground vibration prediction, control and improved rock fragmentation.

Jan 1, 1998

By J E. (Boet) Coetzee

SAFEX International, as the name suggests, is a global organisation, which has the fundamental objective of improving the safety of operations concerned with the manufacture, storage, transport, and use of commercial and military explosives and pyrotechnic products throughout the world. It is a nonprofit making organisation of manufacturers of explosives from all parts of the world, founded in 1954 with the aim of exchanging experiences within the explosives industry. Every third year SAFEX organises a Congress during which members present papers on selected themes and discuss reports of significant incidents that occurred since the previous Congress. Admission is for SAFEX members only, thereby creating a safe environment for discussing problems “within the family”. The XV Congress will celebrate the Association’s 50th anniversary in Geneva where it was founded. An overview of the Congress indicates its structure and covers aspects such as the training event, technical seminars and the themes for the plenary sessions and associated workshops. The paper also highlights the special event for the chief executives of member companies and the review of incidents that occurred in the industry since the last Congress. The Congress concludes with a social programme for delegates and their partners on the last day.

Jan 1, 2005

By Robert Hopler

In the annual report under the Explosives Act for 1905, H.M.inspectors state that over 90 percent of the accidents causing death or personal injury occurred in the use of explosives and under miscellaneous conditions to which the controlling provisions of the Act do not apply, and that such accidents caused 43 out of the 50 deaths, and 312 out of 348 cases of injury. The number of accidents grouped under the heading of “Use and Miscellaneous” is less than that for 1904 - viz., 281 against 301. By these accidents 43 persons were killed and 312 injured, as compared with 39 killed and 343 injured in 1904

Jan 1, 2007

We had a cold, gray winter here in Kansas City and I spent a lot of time watching out my den window at the squirrels and birds trying to get by in the lousy weather. I remember too well working in the cold, loading shots. I was frostbitten several times since I couldn’t tie in MS connectors with gloves on. Those old connectors had a piece of detonating cord on either end of a metal tube that held the delay and you tied them to the trunk lines with square knots. Doing this on a “warm” day in Alaska or Montana shooting ditch for a pipeline could be a frosty experience. Also remember how hard it was to connect up electric caps (detonators to you new guys) in the cold. Now I don’t want you to feel sorry for me ‘cause I suspect most of you younger fellows have also paid your dues in the cold and for that matter in the heat too. Wowee, the heat at the bottom of a Chicago dolomite quarry in August was enough to fry the brains of all that were there. Maybe that’s why the third deck of my brains doesn’t exist.

Jan 1, 2004

By P Geddes, K Grohs, C K. McKenzie, M Morrish

Low grade surface gold mining at the Acacia Resources, Union Reefs Gold Mine in Australia's Northern Territory, involves the excavation of benches in three slices after blasting. Blast patterns span zones of high and low grade ore, as well as zones of waste, and selective excavation is required in order to maintain economical head grades for the carbon-in-leach processing plant.

Jan 1, 1998

By Wang Xuguang, Zhang Xiaozhi, Li Guozhong, Xiong Daiyu

The emulsion explosive is a new kind of water-based industrial explosives that was developed at the end of 1960s. In the 1970s, BGRIMM invented EL-series emulsion explosive that created a new era of water-based industrial explosives technology and products in China. From single type to varieties, the perfect BGRIMM emulsion explosives technology has been formed, which consists of 9 series, over 30 types explosives and related production equipments and processes such as cap-sensitive rock emulsion explosive, opencast emulsion explosive, coal permitted emulsion explosives, low-temperature-resistant emulsion explosive, high-temperature-resistant emulsion explosive, high power emulsion explosive, bulk emulsion explosive for loading truck and powder emulsion explosive. From the early 1990s, BGRIMM successfully developed opencast emulsion explosives and the computer controlled continuous production line of small-diameter cap-sensitive emulsion explosive which raised emulsion explosive production technology of our country to a new lever. With the successful development of powder emulsion explosive and related computer controlled continuous production line, on-site mixed emulsion explosive and loading truck as well, the category of industrial explosives is getting more complete and reasonable. This paper pres ents the history, achievement and development of BGRIMM emulsion explosive technology, also forecasts the future of linked technology.

Jan 1, 2003

By Frank Sames, Brad Terhune

In many construction projects and in most quarrying operations drilling and blasting remains the only feasible method of loosening rock in the removal of rock or overburden, the development of the quarry and in the production process of crushed stone. Often, a blasting plan is required for the project or the quarry’s permit with primary concerns over safety and site security, and compliance with environmental regulations or standards. From this plan, a blasting program has to be developed considering the varying requirements of production, the advance of the mineral extraction and the environmental impact. The actual blast design requires a planning and optimization process. This optimization process is driven by the blasting technicians/engineers, project or mine management and often by community concerns. The blast design process comprises the selection of blast parameters, including the explosives, and the actual layout of the blast. Design tools and controls range from conventional methods based on established blasting practices to advanced design tools or computer models. Blast monitoring and evaluation can also range from empirical to advanced blast assessment. The data and information from each blast or a series of blasts can further be used in the optimization process. Its success depends upon recording the data, the timely transformation of the data to relevant information, and the development of process oriented knowledge. The elements of the blast design process are summarized and described with examples of state-of-the art engineering controls. The reporting and monitoring of individual blasts is discussed with respect to data management and information systems. A conceptual overview of the components and interfaces of a blasting program is given and discussed on the background of technical, management and community concerns.

Jan 1, 2004

By Lyle Dennis

Emphasis on increased production while maintaining rigid quality standards has necessitated a change in blasting technology at Dacotah Cement's limestone and gypsum quarries. The following three methods implemented during the past three years have yielded an increase in production through improved fragmentation.

Jan 1, 1996

By Victor C. Bryan

"One of the more challenging issues facing operators of U.S. mines and quarries is blasting in an environmentally acceptable way. It is quite important that industry management understand and apply guidance, discipline, and control in the exercise of blasting operations. This presentation is a discussion of problems related to that environment away from the blasthole that may or may not be adversely affected by blasting and the steps management may consider in resolving resultant problems. In any case, one of the main concerns that will continuously be brought up is thatmanagement procedures inherent to good blasting is a uxporate responsibility of the mine or quarry business entity; and can not be delegated to the explosive manufacturer or supplier. This management attitude, based on education, training, and the comprehension that the process of production begins with drilling and blasting and consumes a significant amount of overall production costs."

Jan 1, 1995

By Marcello Crispi, Valdir Silva, Juarez Moraes

Companhia Vale do Rio Dote - CVRD is the largest mining company in Brazil and the largest iron ore producer in the world. Serra Geral Mine (SGM) is located at Iron Quadrangle of the State of Minas Gerais, approximately 80 kilometers from Belo Horizonte. Hematite and Itabirite are the two main minerals. A blasting with a spherical charge has been introduced at Serra Geral Mine, an iron ore producer in Brazil, belongs to the CVRD (51%) Kawasaki Steel Corporation (24.5%) others (24.5%), in order to improve fragmentation, as well, load, transportation and crushing productivity. This paper will present the results of a successful blast design with a spherical charge carried out by Serra Geral Mine, the Department of Mining Engineering at Escola de Minas - Federal University of Ouro Preto-UFOP associated to a Blasting Engineering Consultant. The results obtained in the field tests and how it was possible to increase the blast pattern in 53%, which allowed one reduction around 31% in the cost of blasting operation in the Serra Geral Mine, will be discussed in details.

Jan 1, 2002

By Wilfrid Comeau

The RICHTER scale is used in classifying earthquake severity. It is an energy scale giving the estimated energy liberated at the source of the earthquake. Earthquake damage on the earth’s surface, for example at the epicenter - spot on the earth’s surface directly above the earthquake, for a given RICHTER number can vary. This depends on the depth of the earthquake focus. Deeper earthquakes will generally cause a lower level of damage at the epicenter but the damage will be spread over a greater area. As mentioned by Randy Wheeler on Blastserve, each successive RICHTER number represents about a 30-fold increase in energy. This scale is open at both ends with “0” RICHTER equal to about 104 Joules. The lowest level detected by sensitive instruments is about 2 on the RICHTER scale or about 107 Joules. The highest-level earthquake detected at 8.9 RICHTER represents a release of about 3 x 101 7 Joules.

Jan 1, 2003

By Don Bachman, Larry Heywood

Artificial release of snow avalanches, through the use of explosives, is a necessary component of safety planning and operations for ski areas throughout the Western United States, as well as in other alpine regions of the world. Climatic, meteorological and terrain factors leading to the development of avalanche conditions, in addition to release mechanisms and magnitude of the avalanche problem to ski areas will be discussed.

Jan 1, 1999

By Paul Sterk

In underground mining a great deal of time, money, effort, and resources have been used in the effort to minimize blast-induced damage. This damage occurs to the back, ribs, and pillars when the energy of the explosive is released back into the rock due to over confinement or the overloading of explosives in the perimeter holes. This damage can result in roof falls, dilution of ore, excessive rock bolting, scaling, screening, shot-creteing and other safety and support issues.

Jan 1, 2003

The VoD of non-ideal explosives depends on the charge diameter and the thickness, strength and sound velocity of the confiner. VoD measurements are made to evaluate explosives for development, quality control and prediction of field performance. In testing, the container is part of the explosive system and affects the measured VoD. Pipe testing in cardboard tubes delivers the best guide to unconfined critical diameter and minimum VoD range, but the thickness of the pipes affects the result close to critical diameter, even in emulsions. PVC pipes are not good for unconfined test work because they provide relatively strong confinement. Care must be taken to select pipes with constant relative pipe area across the range of diameters. Where pipes are used to evaluate the effect of confinement, the ratio of the wall thickness relative to the thickness of the detonation driving zone in the explosive needs to exceed 0.5 to create full confinement and the ratio of the detonation velocity to the confiner wave speed must be considered. Estimates for critical thicknesses are provided from Non-Ideal detonation models. The relationship between confinement modulus and VoD is discussed and indexes are suggested for quantifying the explosive performance.

Jan 1, 2007

By James A. McGrath

"The predominant key word associated with all commercial blasting methods is “safety”. Safetyshould take precedent over all other aspects of the entire explosives industry which on a wholehas had an excellent track record as to number of injuries per unit of hours worked at all blastsites throughout our country."

Jan 1, 1999

By John Brown

Let’s talk about things that you, the driIl boss, the pit boss and the driller can do to eliminate the trend in drilling related accidents that have come to plague our industry in recent years. My paper will focus on reaI issues, problems and solutions that will affect our everyday outlook and attitudes about our jobs and lives. There are some real hard facts we must address if we are going to reverse this terrible killing trend.

Jan 1, 2000

By Thierry Bernard, Pierre M. Vuillaume, Michel Kiszlo

"In the context of its studies for the trench ministry of the environment and for the French national coal board, INERIS (the French institute for the industrial environment and hazards, formerly CERCHAR) has made a complete critical survey of the methods generally used to reduce the levels of blastingvibrations."

Jan 1, 1996