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By Stephen H. Chung

The SABREX computer blast simulation program permits the study of the effective use of explosive energies and predicts the total performance of a blast in terms of:fragment size distribution: muckpile profile; breakage at grade, column and collar with respect to the control case; crack penetration; damage envelope behind and beneath blastholes; a complete cost analysis including explosives, drilling and accessory costs

Jan 1, 1995

While ring-blasting techniques offer substantial benefits, there are intrinsic problems that are exacerbated when large blocks of ore are mined in attempts to improve the production economics. These problems relate to both the convergence of holes around the ring drive and the charging of up-holes. The size and shape of the ore block concerned should be carefully considered so that good drilling, patterns can be achieved. The hole diameters chosen, both affect and are affected by the size of the ore block. The explosive selected depends on the hole diameter and together with the diameter, determines the nominal drilling pattern. Ring-drilling patterns are best derived through the use of computer software together with engineering judgement. The loading of explosive is necessarily high, and charging patterns require careful thought if overcharging is to he minimised and adequate energy is to be available at all parts of the ore block. Initiation systems are critical to the blasting results, but sub-optimal systems must be adopted if collar priming is practised. In view of all these factors, idealised guidelines can be given for ring design, but it should be recognised that developments in technology may in time change some of these parameters.

Jan 1, 2000

By Shazad Hosein, William Birch, Douglas A. Anderson

This paper will present the results of tests of a new method for assessing explosive performance using wavelet transform analysis of standard blast seismograms. The theoretical background of the method was presented at an earlier ISEE conference.

Jan 1, 2015

By Thomas Hans Kleine

In general the software required by a blast designer includes tools that graphically present blast designs (surface & underground), can analyze a design or predict its result, and can assess blasting results. As computers develop and computer literacy continues to rise the development of and use of such tools will spread.

Jan 1, 1995

By Alexandre Passos, Giorgio De Tomi, Tatiane Marin, Dennis Cremonese, Jacopo Seccatore

"In the mining industry, rock excavation is the first phase of the comminution process. Downstreamoperations such as secondary breaking, crushing and milling terminate the process, reducing the size of the grains down to the desired particle distribution. In such a cascade process, every process upstream heavily influences all the downstream operations. When rock excavation is carried out by drilling and blasting, a very economic source of energy (the explosive) is used at the utmost upstream; a more expensive source of energy (electricity) is employed for all the downstream phases. This means that managing the correct employ of the explosive energy is a form of managing the whole process, controlling the operational costs and therefore the profitability of the whole business. We simulated this cascade behavior, using as a starting point the experimental data obtained from small-scale block blasting, evaluating the influence of blasting on the grindability of the blasted material. This study showed the reduction in visible (particle size) and invisible fracturing (micro-cracking, resulting in a reduction of the Work Index WI). The particle size distribution for full-scale blasts was estimated by means of algorithm simulation, then we simulated the behavior of the comminution plant fed with the material possessing the characteristics previously estimated. All the costs (drilling, blasting, electric energy for the engines of the crushers and mill) were calculated and charted. The results show a clear curve that allows to estimate the minimum operating expenditure (OPEX) for the whole mine+plant framework. Being the WI dependent on the output on the blast, one can manage the performance and the expenditure of the whole comminution process by adjusting drilling and blasting parameters For any given mine, it is possible to perform a simulation and encounter the minimum OPEX scenario for the comminution process and managerial choices can be oriented accordingly. In a cascade productive chain as mining is, responsible strategic choices must be taken looking at the entire production framework. Compartmentalized managerial staff and budgets for separated production areas are not acceptable anymore. Somehow higher costs upstream can lead to effective decrease in costs and increase in efficiency and productivity of the processes downstream."

Jan 1, 2016

By Per-Anders Persson

This chapter deals with the concepts ofshock waves aud detonation waves together, because a detonation wave is really a shock wave, supported by the explosive reaction that the shock wave ignites and propagates as it travels through the explosive material. In the context of rock blasting, furthermore, there is justification for treating shock waves and detonation waves together, because the mechanical effect of the detonation in an explosive in a drillhole in rock is propagated and its effects are spread throughout the surrounding rock by means of a shock wave The overall performance of an explosive in rock blasting or any other application is of course dependent on how much thermal energy is released in the chemical reaction that occurs when the material detonates, and on how much useful mrc!~amcal work the reaction products can do as they expand. A major portion of this chapter deals with the prediction and measurement of explosive performance, a subject which is now still in a process of rapid development.

Jan 1, 1994

By M. Ganster, H. Krenn

The mission of the project is the fast and cost-effective rehabilitation of decommissioned lignite mining and coal upgrading facilities. This is necessary to ensure the successful future utilization of these sites. On the one hand, for founding new industrial and commercial facilities and on the other hand for touristic activities.

Jan 1, 2013

By Frank Sames

The control of the environmental effects, especially blast vibration and airblast, has become a dominating planning criterion for most surface blasting operations. Compliance with existing regulations is generally achieved through constraints in the blast design, or monitoring programs. Commonly, blast vibration and airblast signals are rated and compared only by their maximum amplitude and the principal frequency associated with the peak.

Jan 1, 1997

By Stewart A. Silling, Dale S. Preece

The two key results of rock blasting are fragmentation and movement of geomaterials. Movement/flow of the blasted rock is often referred to as heave. Modeling the movement of full scale blasting is now possible with 3D distinct element models and parallel processing.

Jan 1, 2016

By Rob Farnfield, Ben Williams, Ashley Haslett, Diane Cartledge

Major accidents that occur within our industry are often tragic and expensive, damaging reputation and threaten the livelihood of the business. There isn’t anything in them that can be seen as positive for those that experience them. They undertake what are usually very painful, detailed and time consuming investigations to discover how the incident occurred and what needs to be done in the future to prevent similar incidents occurring. Many admirably choose to share the lessons learnt through industry organizations such as SAFEX International so that we can all have the opportunity of preventing similar incidents from occurring within our own organizations.

Jan 1, 2016

By P D. Katsabanis

According to Persson(1) steady state detonation along a cylindrical charge can be regarded as a self propagating process in which the axial compressive effect of the shock front discontinuity changes the state of the explosive so that exothermic reaction sets in with the requisite velocity.

Jan 1, 1990

By Phillip R. Mulligan, Kevin Gantz, Aaron J. Ward, allen shirley, Sean Treadway

Understanding the impulse transferred into a structure by the coupled two-phase loading produced by an explosive charge buried in soil is of interest for various applications. The most common impulse measurement technique involves a buried explosive charge and a steel plate/test structure suspended above the charge. Upon detonation of the charge, the soil and overpressure heave the plate into the air. The plate’s trajectory and velocity provide the necessary information to calculate the total impulse transferred from the charge configuration.

Jan 1, 2016

By C B. McCampbell, R W. Jr Bickes

Sandia National Laboratories has developed a semiconductor bridge (SCB) igniter for the ignition of a variety of explosive materials. When subjected to a low-energy current pulse, the bridge bursts into a plasma causing rapid ignition of the explosive material pressed against the bridge. Despite the low energies required for ignition, SCB components have proven to be explosively safe, meeting both no-fire and electrostatic discharge (ESD) safety requirements.

Jan 1, 1991

By H. Venkatesh, Balachander R.

This article discusses the method that was adopted for controlling damage to rock mass while excavating an underground powerhouse cavern at Tala Hydroelectric Project. It discusses in detail the near field vibration studies carried out and the safe vibration levels established for that rock mass condition.

Jan 1, 2006

By John E. Wiegand

This study will discuss the AMAX Coal Co., Penndiana Pipeline Project, which was conducted in conjunction with the following parties: AMAX Coal Industries, (U.S.B.O.M.) United States Bureau of Mines, (I.D.O.R.) Indiana Division of Reclamation, Ohio Valley Pipeline, Inc., New Mexico Tech, and ourselves, VIBRONICS, INC., Evansville, Indiana. The purpose of this study was to find a safe vibration level for active gas transmission pipelines near surface coal operations.

Jan 1, 1994

By Douglas Bartley, Brian Wingfield, Robert McClure

Recent studies and limited tests indicate favorable results utilizing high accuracy electronic detonator technology over conventional non-electric pyrotechnic systems. This study discusses the application of this technology using the Daveytronic programmable system in an on-going production basis. The study quantifies the performance as it relates to fragmentation, excavation, vibration and productivity in an eastern U.S. aggregate mining operation.

Jan 1, 2001

By Frank Sames

Most Blasting Programs are developed focussing on the environmental impact with respect to blast vibration and airblast. Compliance with existing regulations or policies limiting the immissions are generally achieved through constrains in the blast design, or monitoring programs. Efficient monitoring programs combine compliance monitoring and blast assessment. Signals, which are obtained in the area of direct influence of the seismic source, can contain valuable information about the blast design parameters. Techniques to analyze blast vibration signals have advanced and can assist in understanding the contribution of individual blast parameters to blast vibration and airblast. Advanced signal analysis encompasses magnitude analysis, Fast Fourier Transforms (FFT) and frequency scans in the frequency domain, as well as filtering in the time domain. Through examples, the advanced signal analysis techniques and their limitations are described and discussed, showing the impact of blast timing, timing accuracy, charge configuration and the geology dependent transmission behavior. Optimization criteria and pragmatic monitoring programs can be developed on the basis of the most influential blast parameters. In addition, however, safety and the cost efficiency of the blasting program are essential to the success of an operation. That is where advanced signal analysis techniques can interface with blast planning, computer assisted modeling and information systems. A valuable process can be developed to ensure compliance with existing regulations and efficient risk management for mining operations, while tracking cost and supporting operational decisions. A conceptual blasting information system is presented.

Jan 1, 2000

By Paul Sainato

Recruiting and retaining students in the explosives industry is becoming increasingly important each year. With no undergraduate degree in explosives engineering currently available in the United States, it is from other industries and degree disciplines we must recruit. The 2014 annual ISEE conference saw the first anonymous online survey distributed to members of SEE student chapters of the International Society of Explosives Engineers. The survey contained questions about future job and career plans, ideal job placement, expectations of salary and current academic degrees. The purpose of the survey was to determine what these students expect or require from a career in the explosives industry, and their current path to pursue this. This information can help steer recruitment activities and job offers for graduating students. The success for both student response rates and interest from the industry has allowed space for a yearly update of this survey. A second survey was distributed in 2015 and included international students. This paper provides the data from a third online survey distributed to all student members of the International Society of Explosives Engineers, globally. Understanding the main incentives for a student to accept a graduate position as an explosives engineer can help us, as an industry; position ourselves to remain competitive in recruiting against other major degree disciplines.

Jan 1, 2016

By Stanley Griff, William Herrera, William O. Seals

"The Navy initiated liquid propellant research in the early 1940's. The first promising Navy liquid propellant, Otto Fuel II, was developd in the early 1950 as a potential torpedo fuel. Later, the Navy developed a HAN based liquid propellant designated NOS-365, a hydroxylammonium nitrate, isopropylammonium nitrate and water formulation. A large gas volume generated by this propellant produced a large wake behind the torpedo. As one can readily understand, this negated the useof the propellant for this application. Recognizing the large gas volume as a desirable propulsion system for guns, the Navy embarked upon a gun propellant proqam. Utilizing a bulk loaded gun sysytem, the program failed when the gun was destroyed by the propellant detonating."

Jan 1, 1990

By Daniel Hauer

Blocking. (5) The “blocking” of boulders is a much cheaper way of breaking them up than “mud capping.” It should always be used in preference to that method except when too much time will be consumed by a crew of men waiting for the drilling to be done, as shown in example of cost No. 1, as given under “mud capping.” Under such circumstances the time consumed would be a greater cost to the contractor than the extra amount of dynamite. Then, too, on large thin boulders to drill one hole would result only in breaking the stone into such pieces as would again have to be broken; and the many holes might equal the cost of extra dynamite. Under such circumstances if method (6) cannot be used, “mud capping” will have to be resorted to, to do the work economically.

Jan 1, 2006