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By Neil T. Davie, Thomas K. Blanchat, Thomas C. Togami, Joe R. Weatherby, Dale S. Preece, Robert A. Benham, James J. Calderone

"Geotechnical structures ,such as underground bunkers, tunnels, and building foundations aresubjected to stress fields produced by..the gravity load on the structure and/or any overlyingstrata. These stress fields may be.. reproduced on a scaled model of the structure byproportionally increasing the gravity field through the use of a centrifuge. This technology canthen be used to assess the vulnerability of various geotechnical structures to explosive loading.Applications of this technology include assessing the effectiveness of earth penetrating weapons,evaluating the vulnerability of various structures, counter-terrorism, and model validation. Thisdocument describes the development of expertise in scale model explosive testing ongeotechnical structures using Sandia’s large scale centrifuge facility. This study focused onburied structures such as hardened storage bunkers or tunnels. Data from this study was used toevaluate the predictive capabilities oft existing hydrocodes and structural dynamics codesdeveloped at Sandia National Laboratories (such as Pronto/SPH, Pronto/CTH, and ALEGRA)."

Jan 1, 1998

By Cam Thomas

The initial application for reflectorless laser technology was for profiling rock faces to determine front row burden and improve flyrock control and airblast. Over the past fifteen years a number of laser systems have been developed for general ground modeling purposes and GPS offsets, but these advances have yet to gain common acceptance in construction, mining and quarry blasting. This paper will outline a number of applications for reflectorless laser technology, including the latest method for rock face profiling, mapping, and 3-D modeling to calculate available and excavated rock volumes. Drilling deviation measurements will be presented in conjunction with rock face profiling to demonstrate how this information can be used to improve blast results. In complicated excavations, the actual quantity of rock excavated for payment purposes and the amount of overbreak can be very controversial. Procedures to calculate these volumes using laser technology will be outlined and comparisons will be made between these results and traditional techniques.

Jan 1, 2003

By Gary Cavanough, Stuart Addinell, Hector Parra

Drilling deep, straight, accurate holes in hard rock to achieve efficient blasting is a challenge for the mining/quarrying industries with short holes normally drilled using “top hole hammer” (THH) and deep holes using “down the hole Hammer” (DTH).

Jan 1, 2013

By Ruilin Yang

The following simple equations are frequently used within the blast vibration community;PPA f PPV v = 2p · , PPV f PPD d = 2p · ,a f PPV PPA 2p = , and v f PPD PPV 2p = where, PPA is the peak particle acceleration, PPV is the peak particle velocity, PPD is the peak particle displacement, and fa , fv , and fd are the frequency of the particle acceleration, particle velocity, and particle displacement vibration waveforms, respectively. Conceptually, the frequency should be selected to be the frequency of a simple sinusoidal wave that is used to approximate the blast vibration. In the literature, f is sometimes chosen as the dominant frequency (fdm) estimated from the Fast Fourier Transform (FFT) of the blast vibration wave, on other occasions, f is chosen to be the principal frequency (fpr) from the vibration cycle with the peak vibration amplitude.

Jan 1, 2012

By Richard R. Brochu

At the International Society ofExplosives Engineers Annual Conference held in Nashville, Tennessee in February 1995, a Seismograph Standards Committee was established. The purpose of this wmmittee was to develop objective performance specifications for vibration measurement instrumentation and field use practices. It was also understood that due to geology, temperature, and moisture in the soils, it is not possible to design and build an instrument to give ‘results which are absolutely comparable for ground vibration. It was, however, considered essential to standardize instrumentation by which vibration can be measured under closely defined conditions so that results obtained by users of seismographs are always the same ,&thin stated tolerances.

Jan 1, 1998

By George D. Raitt

Anyone who has spent any time in and around the drilling and blasting profession knows that probably the most critical part is the drilling portion. A blasthole is nothing more than a cylindrical vehicle designed and strategically situated to hold and contain an explosive charge so that it can be detonated in the most efficient and optimum manner possible. It matters very little if the latest “State-of-the-Art” explosive or detonation system Is employed if the hole is poorly placed; i.e. excessive burden and spacing, sized incorrectly for desired results, insufficient in depth etc.. This is not to mention that the drilling phase is the most expensive, requiring sizeable initial outlays and upkeep. It’s also true that improper drilling can cause costs to skyrocket throughout the remainder of the work cycles such as excavating and hauling, crushing, screening and so on.

Jan 1, 1990

By Randall Wheeler, R. Frank Chiappetta

2000 HIGH-TECH SEMINAR Blasting Technology, Instrumentation. and Explosives Applications - Orlando, Florida, USA July 24 - 27,200O 2000 BAI - PROTECTION AGAINST LITIGATION WITH GOOD PRE-BLAST SURVEYS, DAMAGE INSPECTIONS AND RECORD KEEPING 1 of 65 Good Record Keeping is Essential for: 1 ) Compliance with any prevailing Local, State or Federal Regulations, ordinances and permits. 2 ) Protection against potential litigation. 3 ) Balancing explosive consumption, use & costs. 4 ) Use in blast designs.5 ) Blast diagnostics & troubleshooting good/bad shots.

Jan 1, 2000

By Dean Nichols, Matt Ortel

Explosive accidents in the United States have brought increased attention to emergency operation plans (EOP) at all facilities that manufacture, transport, or store hazardous materials – particularly explosive materials. Explosions are sudden, powerful, and complex events that are difficult to characterize in terms of the thermal, over pressure, and debris effects. Industry, regulatory, and public officials require emergency response planners to not only anticipate the blast effects of an explosion, but also to prepare an appropriate response.

Jan 1, 2016

By J M. Laboz Bernard

Among the numerous technical evolutions in the blasting environment we are going to describe below the concep

Jan 1, 1995

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 Thierry Bernard

This case study shows how a unique combination of field measurements and advanced technologies allowed blasters designing, loading and firing an incredibly challenging quarry blast.

Jan 1, 2015

By Ali Kahriman, Abdulkadir Karadogan, Umit Ozer, Mehmet Aksoy, Kagan Ozdemir, Adiguzel Deniz

This paper presents the results of ground vibration measurements induced by blasting during the construction of the Istanbul Kadiköy-Kartal metro tunnel which has been driven at a depth of approximately 20-40 m deep under a highly urbanized region of Istanbul city in Turkey. This tunnel is being constructed by a joint venture group. The formation encountered during the construction is classified as hard and strong rock by laboratory and field tests performed by the joint venture group. Within the scope of the study, for the prediction of the peak particle velocity and to determine the slope of the attenuation curves together with the maximum charge per delay for the S4 shaft tunnels and S12 shaft tunnels of this tunnel route, ground vibration components were measured carefully by using four vibration monitors (Instantel Minimate Plus model) during the advancement of the tunnels which required blasting. The particle velocities and frequency values of all blast events are evaluated according to the United States Bureau of Mines (USBM) and German DIN 4150 Norms in order to predict, and compare the influence grades to the neighbouring buildings, and structures. Also, data pairs of scaled distance and peak particle velocity obtained from 114 records at S4 shaft tunnels and 79 records at S12 shaft tunnels were analysed statistically. Empirical relationships with correlation at the 95 % confidence interval were established for different rock units (diabase and arkose) and suggested for the test sites in order to estimate particle velocity of the ground vibrations.

Jan 1, 2007

By D. J. Goodings, R. J. Bonenberger, H. U. Leiste, W. L. Foumey

This paper describes a series of two-dimensional tests conducted and filmed with a high-speed (500 frames per second) video camera. The purpose of these tests was to provide a better understanding of the processes involved in creating craters and channels in water covered soils with explosives.

Jan 1, 2000

"AQUILA Mining Systems Ltd. is a Canadian company that designs and develops monitoring, control and navigation systems for the surface and underground mining industries. In 1992, AQUILA Mining Systems began the development of technology for monitoring, controlling and positioning mobile mining equipment. In 1993, AQUILA completed its first field test with GPS receivers onboard ablasthole drill, and thus demonstrated the viability and strategic relevance of this technology in surface mining. Since then, AQUILA has installed GPS-based technology on drills and shovels in several Canadian mines. This paper will review the development of these systems and discussthe benefits the mining industry could realise through their production implementation."

Jan 1, 1997

By Dan L'Heureux, Joe Haid, Stephen H. Chung

Most coal deposits in Western Canada involve steeply dipping multiple seams. An efficient way to recover coal seams would be to drill through the seams and blast both the overlying and underlying waste material in one shot without disrupting the coal seams while fragmenting the waste rock for easy removal. This requires special blasting techniques as reported by Chung and Jorgenson in 1985.

Jan 1, 1998

By Michael S. Wieland

Toxic fumes cause fatal and nonfatal incidents in underground mining, where the working environment tends to trap the fumes, hindering the restoration of nonharmful conditions. Workers can underestimate the residual fume toxicity and return to the work site too quickly. The toxic fumes from charge explosions depend upon a number things: formulation ingredients, mixture uniformity, water resistance, hole contaminates, rock hardness, and dust interactions. Hole-to-hole shock waves and rift compressions can partially desensitize charges, ruin the reaction kinetics, and worsen the fume toxicity. Traditionally the fume hazards for candidate explosives are resolved for a restricted set or tally of theoretical or measured fume components, transformed to standard reference conditions. The relative fume toxicity RFT is the resultant influence reckoned from a formulated sum of concentrations within the tally that are unweighted or weighted with chosen multiplying constants. The RFT result is compared to a rule criterion that represents the worst case tolerable fume toxicity stipulated by regulations or otherwise. The ranking and comparison of different hazard potentials that would otherwise remain unwieldy is rendered tractable by the common format of the RFT notation.

Jan 1, 1998

By Dale Preece, Steven Sobolik, Richard Jensen

Recent events demonstrate that civil and government facilities and structures face an ever-increasing need to be designed for protection against malevolent explosions. Modification of existing public structures and especially design of new ones increasingly includes provisions for explosive protection. ISEE members endorse and promote responsible application of explosives to benefit mankind and deplore any other use. However, our knowledge of explosive behavior and our ability to predict the results of explosive events puts us in a unique position to give guidance to designers of civil and public structures. Recent advances in computational methods have resulted in new computer codes with ALE (arbitrary lagrangian eulerian) simulation capabilities. Historically, lagrangian computational methods have been used for modeling solids because the mesh or discretization moves with the material. Rock breakage resulting from explosively induced shock-waves has been successfully modeled with lagrangian codes. Explosive detonation has traditionally been modeled with eulerian techniques. Eulerian methods have been used to model gases and fluids, tracking the material as it moves through the computational grid. ALE computational technology couples the two methods together in a manner never before possible. An ALE simulation can accurately treat the explosive detonation, interaction of explosive gases with air, and the impact of explosive event on nearby solid structures. ALEGRA (Budge et al. 1997 a & b) is an ALE code developed at Sandia National Laboratories. ALEGRA simulations accurately predict the explosively induced impulse on the structure to be protected. It has been applied to the analysis and design of blastwalls to protect structures and people from explosive events. The impulse calculated can be used by structural engineers to design a blastwall. ALEGRA has also been applied to predict the effect of a blastwall on explosion overpressure some distance behind the blastwall to assess the effect on people present during the event.

Jan 1, 2000

By Robert Hopler

This article, advocating having employees whose specific job would be to fire blasts in underground coal mines in llinois, was written 5 years prior to the establishment of the U.S. Bureau of Mines, and 2 1/2 years before the worst month in U.S. coal mining history, when 692 miners were killed in three separate explosions in December 1907. Obviously something had to be done to improve safety in the use of explosives, and having dedicated shotfirers was a good first step.

Jan 1, 2006

By Ron Lutz

In today’s world, production is the name of the game. We are all in business to make money. In the Quarrying and Mining industry the same holds true. The primary goal is to develop the best drilling and blasting program available to maintain uniform fragmentation to maximize production. Also we want to maintain drilling and blasting costs and minimize escalators. This paper is intended to discuss ways for all parties (quarry’s, blast service and drill companies) to attain this through understanding what can be done to help blasthole drilling and production. Blast designs and seminar’s emphasize the accuracy of drilling to produce better fragmentation. Blast design must also include basic concepts in the drilling process. The type of drill to be used for example whether it is a crawler or truck mount, top hammer or down the hole is important. Quarry operators have a role to play as well. They hold the key to the production of drilling. What the customer does or does not do has a direct effect financially to the drilling. The phrase of pay me now or pay me latter comes to mind. This paper will explore the detail of planning that is required by the quarry and/or blast service companies before a single hole is drilled. The drill must be able to meet the production need of the operation. The type of drill available and what can and cannot be done. The drill cost must be competitive. This paper will touch on comparison drill costs from 1967 to 1999.

Jan 1, 2000

By A Bagchi, Nabiullah, Jagdieh

"A number of coal mines in India are affected by fire. Most of coking coal reserves in the country are located in Jharia coalfield where more than 18 sq. km is in the grip of fire. Generally such fires are confined in areas near to our crops. About 37 million tonnes of coking coal are lost in recent yearsdue to fire and another 48 million tonnes are blocked in fire areas. Preventive measures adopted to control fires were only partially successful and the cost of such measures was exorbitant I Temperature of blast holes in fire area varies between 60 and 300° C or even more. Even after thorough quenching of holes with water, it become difficult to bring down the temperature below SO"" C. For blasting hot holes primary need is to select safe and suitable commercial explosives and detonating fuse and to measure hot hole temperatures. VWiOUs types of commercially available explosives including Nitro Glycerine bare, slurries, site mixed slurries (SMS), emulsion5 ,detonating fuses and detonators were tested to determine their thermal behaviour at elevated temperatures under field simulated conditions in the Copyright © 2000 International Society of Explosives Engineers 1993g - Studies on Safe Blasting Technique in Fire Area of Coal Mines laboratory and in hot blast holes in field . More than 50 round of blast were conducted in fire areas. NG base compositions and detonators were found unsafe at temperature above SO0 C andtherefore, they are not permitted to be used in hot holes. Slurries and emulsion are stable upto 1200 c. For blasting at temperature exceeding SO0 C a heat resistant gel/ solution was developed by the authors and is being used in number of fire areas."

Jan 1, 1993