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By Joshua Hoffman, Braden Lusk, Kyle Perry

This study explores how different geometries affect the shock tunnel’s performance and is broken down into three phases. Phase 1: Open arena testing in which theoretical energies produced by the detonation of small (<1.0 kg) charges are compared to actual experimental values. Phase 2: Shock Tunnel testing in which realized energies are experimentally recorded for the UK and S&T shock tunnels. Phase 3: Analysis of the data to begin building a pressure-forecasting tool for the UK shock tunnel given the explosive characteristics, sample size and desired pressure and impulse.

Jan 1, 2009

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 William H. Highlands

Lightning is a natural phenomenon which poses a potential hazard to people, structures, and equipment unless adequate protection is provided. The type of protection required is related to the nature and of the facility. The decision making process involves a number of interrelated factors which should be considered when determining the need for protection.

Jan 1, 1989

By Gordon Revey

The challenge of managing blasting risk, types of risk, public perception, and a system for managing risk were covered in the first part of this article in the May/June 2000 issue of the Journal of Explosives Engineering. This final part of this two-part series provides a method for identifying specific blasting risks and reviews the importance of community relations.

Jan 1, 2001

By J Silva Castro, Braden Lusk

Information management is important in all disciplines. In mining; collection and analysis of information before, during and even after mining is a keystone to performance. During mining, information is useful to optimize the resources and make appropriate decisions. Current technologies allow for collecting information in real time. Records of blasting activity at the mine are common practice in surface coal mining operations. The most common blast information recorded contains the location of the blast, scaled distance, geometry of the blast, weight of explosive used and quantity of blasted rock. Sometimes due to the proximity of protected structures, seismograph evidence of the particle velocity and airblast levels is required. However, in the majority of cases, the seismograph information is not linked to the blast information. Blast related information is recorded separately from the seismograph information and seismograms are little more than an attachment to the blast record. This fact makes simultaneous visualization and analysis of the technical details of the blast with the vibration and airblast information difficult.

Jan 1, 2012

By Adrian J. Moore, Alan B. Richards

Responsible blasting requires that rock throw be controlled to ensure that no danger will result to people and property. This paper describes the development and testing of empirical field calibrated formulae that can be used to evaluate rock throw, provide an early warning of when reduced burden will endanger people and property, and prevent flyrock incidents. Inputs to the formulae are charge mass, burden or stemming height, and a site constant that lies within a general range that can be tightened by site calibration. The output is the distance that rock will be thrown, and this ‘design your own flyrock’ quantification can be used to establish both safe clearance distances, and the critical range of burdens and stemming heights where the situation changes rapidly from safe to hazardous. Examples are given of the use of the model to control flyrock in open-pit mining and quarry operations, in situations which are controlled by both burden and stemming height.

Jan 1, 2004

By Mick Fritz, Tom Treleaven

The success of any blast is dependent on the accuracy of the blast design and field controls placed at the shot location. The procedure by which the data is collected and analyzed is paramount to accomplishing the anticipated blast results. lf the geometry of the blast is not measured correctly, then the results will not meet expectations. Measuring the geometry and compensating for bole hole deviations is crucial not only to the lnitlal blast but also for any consecutive blasts. Excessive bore hole deviation can cancel any new technology in use. However the instruments and skills required solving this Issue are readily available.

Jan 1, 1998

By Matt Slezak, Tristan Worsey, Nathan Rouse, Kyle Hall

As everyone knows, blasters are required to file blast reports of every blast for regulatory purposes. To this day, the authors see many handwritten blast reports. Handwritten blast reports are notorious for containing errors or omissions. This is not because the blaster intends to misreport information. It is because blasters have many tasks to complete in a day, are sometimes in a rush, and could accidentally miscalculate data, omit items, or record incorrect data. In most cases, blasters do not suffer consequences to these errors because blast reports are seldom reviewed in detail. In some cases, such as when a blasting operation undergoes some sort of litigation process, the reports are reviewed in detail and the blaster is ultimately held responsible. If the reports contain errors, the blaster can be fined, have his/her license revoked, or worse. Electronic blast reporting and centralized data management can help reduce or eliminate the potential for accidental blast reporting errors to occur. This paper presents many ways that electronic blast reporting can reduce or eliminate blast reporting errors, decrease time and extra costs spent reporting, and improve efficiencies in the field and the office.

Jan 1, 2018

By Anthony J. Konya, Calvin J. Konya

Mine sites and construction projects have faced problems with blasting a smooth back wall. This lead to safety concerns with slope stability and rock falls from the walls. Decades ago Dr. Calvin Konya began a special type of blasting called “Precision Presplitting”. This form of presplitting used relatively light loads based on the rock type being blasted. The explosive loads were estimated for each rock type and adjusted as blasting progressed. This current research project also determined a new equation for prediction of the ground vibration from one type of presplitting and compared it to vibration from production blasting.

Jan 1, 2016

By S A. Steyn, P Terrett

Air decking has become a widely practised method internationally for modifying fragmentation results and providing cost savings from reduced explosive consumption. Duvha has been applying air deck technology to overburden and midburden blasting for a few years. A thorough evaluation of air decking at Duvha has been made by instrumenting a number of blasts and analysing costs from direct savings in reduced explosives costs to savings in improved dragline productivity.

Jan 1, 1995

By Mohsen Sanai, Paul Gefken

"SRI International has developed and patented* a castable dilute explosive tile @ET) that offersunique advantages over conventional high explosive. The primary advantages of DET are that itsdetonation pressure can be adjusted over a wick range and its impulse can be controlled independently by adjusting its thickness and configuration. Because DET has a much lower detonation velocity than conventional explosives, the pulse duration produced by DET is as much as 10 times longer than the pulse duration produced by conventional explosives for equal explosive weights. These features of DET present several advantages to the mining industry. For example, DET can be tailored so as to control fragment size and distribution to enhance extraction of desired elements from ore or breakup of specific regions."

Jan 1, 1995

By Harry Verakis, Thomas Lobb

In the past decade, approximately 5 billion pounds of explosives were used annually in the United States. Most of this quantity of explosives was used by the mining industry and coal mining was the dominant application for explosives. Considering the large amount of explosives used, the accident safety record for the mining industry has improved significantly over the past two decades. Blasting accidents are usually a small percentage of the total number of mining accidents. However, blasting accidents continue to occur and the severity of these accidents is disproportionately high with respect to other types of mining accidents. This paper is a summary and an update of the surface mine blasting accident investigations and studies conducted previously by the Mine Safety and Health Administration (MSHA) and the former U.S. Bureau of Mines.

Jan 1, 2001

By Robert Martin, Brian W. Stump, David P. Anderson

2We use field measurements to quantify physical processes that accompany different types of mining explosions. The data sets collected include three-component ground motion, acoustic, video and high speed film, three dimensional topography, geological and geophysical properties, design blast pattern and timing, and velocity of detonation in the explosive for individual borehole detonation times. The explosions include simple single-fired contained explosions, ones designed to bulk and fracture material and those that cast material. Our goal is a physical understanding of these sources for the purposes of optimizing blasting practices.

Jan 1, 1998

By C. McAllister, D. Preece, J. Berendzen

The Multiple Blasthole Fragmentation (MBF) model was developed recently and has been reported in previous papers. The MBF model accepts inputs from the blast design, such as: location and orientation of each blast hole, stemming length, blast hole diameter, multiple decking, bench height, initiation sequence, etc. It models the effect on fragmentation of delay timing with its associated scatter for each blast hole. MBF has a statistical modeling capability for geological random variation of the attenuation of particle velocities. Also simulated is wave reinforcement due to the interaction of simultaneously arriving waves or diminishing cooperative contribution from long delay intervals between charges.

Jan 1, 2016

By Sang Ho Cho, Masaji Kato, Masaaki Yamamoto, Masaaki Nishi, Katsuhiko Kaneko

This paper presents a numerical simulation method to predict rock fragmentation and to verify a fracture mechanism by bench blasting. The rock fragmentation, which has been used as a means of the index to estimate the effect of bench blasting, affects the expenses for loading, conveyance and crushing of blasting muck piles. The developed numerical simulation method is based on the finite element method and fracture mechanics and includes the re-meshing procedure to express the fracture process of the rock mass. This paper discusses a procedure for a determination of size distributions of the results, which were calculated by numerical simulation, including the tines.

Jan 1, 2002

By Reinhold Schnell, Piers Wendlandt, Nathan Rouse

Drilling and blasting are key components of every hard-rock (i.e.,metal/nonmetal/coal) mining operation. Well-executed and maintained drilling and blasting can have a major positive impact on the overall success of such operations. This case study presents the implementation of a new drill and blast engineer position and systematic improvement of the drill and blast operations at a surface metal mine. The findings of and lessons learned from this case study can be applied toother mine operations to improve safety, production, efficiency, and cost savings. Focus areas for the project included refined communications, operational practices and procedures, planning, designing, and data collection and analysis. This case study showed improved efficiency in communication and planning among the engineers, operations team, and contractor groups over the course of the project. An increased awareness of long-term plans and needs for the drills and blasters reduced or eliminated existing delays. Test blasts that implemented new drill and blast designs and updated operational practices and procedures were tested to streamline the process. Constraints regarding explosive product shipments, geological considerations, and a uniform powder factor provided the basis for new blast designs.

By C. Sawmliana, P. Pal Roy

Near-field blast vibration response of restrained pipelines either buried or exposed was studied during rock excavations at sensitive locations for Stage-II (4x500 MW) commissioning work in a super thermal powerplant of the National Thermal Power Corporation Ltd. (NTPC) of India. The existing running plant of capacity 1000 MW has many important installations including pipelines of varying diameters. These pipelines were very close to the blasting locations (mostly within 12m). Blast optimization and consequent monitoring of vibrations were carried out simultaneously for more than 250 experimental blasts conducted by the authors. This paper emphasized, particularly, on the safety of pipelines and their responses due to repeated blasting impacts. A few guidelines supported by theoretical derivations are provided for futuristic research.

Jan 1, 2001

By Lon Santis, Dale Ramsey

The use of aircraft to support blasting operations in mines, quarries and construction sites goes back to the early days of aviation. Invaluable at times, aircraft use has been limited by cost, the unpredictability of weather impacts and other factors. Recently several technologies have matured to open up a new way to acquire aerial data with unmanned aircraft systems (UAS), commonly called drones. Equally important, the U.S. Federal Aviation Administration has recently implemented an exemption process and rulemaking to implement the commercial use of UAS into the United States’ National Airspace. The skies are opening for many applications of UAS. The most notable may be photogrammetry, which is the science of making measurements from photographs, especially for determining the exact positions of surface points.

Jan 1, 2016

By Cceliksirt, V Erkan

This computer program has been developed under the field conditions for use in control of surface drilling-blasting operations. This paper outlines the relevance of fragmentation to quarrying, open pit mining or road cutting and key features and operating principles of the software (DelPat for Windows 95).

Jan 1, 1998

By Brad Bulow

Blasting is an essentially violent process aimed to disrupt and loosen rock for productive excavation. Some dilution of any ore present is the inevitable result. This makes blasting a dirty word to most geologists, particularly in narrow vein gold mines. A 1% increase in gold recovery may be worth $1 M extra revenue to a large mine.

Jan 1, 2000