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By P. N. Worsey, M. Schmidt

Many advanced military systems and civilian power generation concepts postulate the availability of compact sources of electrical power capable of delivering gigawatts over microsecond time scales. For example, such a compact power source is essential for future practical pulsed high-powered microwave sources. An explosive-driven flux-compression power generator (EDPG) could fill this requirement. A basic strength of this concept capitalizes on the inherent high energy density storage capacity of modern chemical explosives. It relies on the physics of magnetic flux compression to convert that stored chemical energy into very large amounts of electrical power over short time scales. The generator also has the additional advantage of employing the same types of explosives that are already routinely used in conventional munitions. However, the self-destructive nature of this type of power generator places serious limitations on power pulse-lengths and ranges of applications. This paper describes how a multi-disciplinary team led by researchers from the University of Missouri-Rolla (UMR), Texas Tech University (TTU), and Texas A&M University was awarded a grant by the U.S. Air Force Office of Scientific Research to perform basic research to resolve several fundamental EDPG problem areas. Described are the utilization of UMR’s extensive explosives research expertise and facilities to investigate questions of energy conversion efficiency and the mechanics of energy production. Also, UMR explosives researchers will provide inputs to improved dynamic computer models of the complex, intertwined physics and chemistry operative in these devices. In addition to explosives expertise, UMR provides facilities for basic explosives material research, as well as the storage, machining, and formulation of explosives. UMR researchers are also using test facilities and data collection equipment at the Rock Mechanics and Explosives Research Center and at the UMR Experimental Mine to perform “proof of principle” and subscale tests of explosive-driven flux-compression power generator components. An integral part of the paper is a description of the development of an extreme intensity flash system by UMR and TTU to allow for the high-speed photography of EDPGs in operation. This multi disciplinary research program offers major advances regarding the size, weight, and electrical characteristics of compact EPDGs. Such breakthroughs could dramatically accelerate the practical realization of systems currently under study. Also, these power sources may have far reaching relevance to other Department of Defense and certain commercial compact power applications.

Jan 1, 2000

By J. Fresnillo, M. Lopez Cano, S. Burgada, P. Couceiro, A. Jafa

This paper explores the sustainable use of the explosive’s energy for rock blasting and its role on the performance of downstream unit operations in mining applications. Since energy efficiency is becoming important for long term mining strategies, cost-effective optimization strategies are required to increase productivity and revenue while minimizing environmental impact. These optimization strategies involve continuous ability to model and measure all related phenomena and operational performance, integrated under a continuous improvement program where all involved counterparts act in close coordination. Although mining is complex, it can be regarded as a set of interconnected processes, where energy is consumed in a sequence, following all unit operations from the pit to the concentration. In this sense, the performance of downstream operations is potentially influenced by the initial energy input, since the explosive is the source of all energy used for rock fragmentation and heave. In this line, sustainable energy blasting is recognized as one of the main strategies for mine energy optimization projects. Finally, a special case study from an important gold mine in South America is presented, where benefits of a sustainable blasting energy strategies has been proved to deliver important downstream benefits.

Jan 1, 2019

By Steve Collinsworth

Sometimes, for those of us in the right place at the right time with the right product, necessity creates opportunity. Such is my case at a West Virginia coal mine where a mine manager was desperately seeking a way to eliminate coal damage on cast shots while maintaining cast percentage without the expensive process of secondary drilling. This paper will focus on how bottom hole air decking is solving the problem.

Jan 1, 2000

By Cameron McKenzie, John Heilig, Patrick Andrieux, Andree Drolet

It is widely accepted that both underground and surface blasting operations can de-stabilise excavations to the point where it can threaten the feasibility of mining through personnel safety or OK dilution. Research has been undertaken to outline a practical method in which the impact of blasting will be accounted for during the early excavation design stage by modelling, and during the following production stages by monitoring rock response to blasting operations.

Jan 1, 1994

By Sharkey Bowers

This study was undertaken in order to determine a conservative estimate of the attenuation rate of vibrations through the shallow limestone in South Florida due quarry blasting. The natural limestone bedrock in occurs at or near the surface in southeastern peninsular Florida. While the shallow overburden soils is advantageous for mining purposes, vibrations from blasting has been a contentious issue in South Florida due to the proximity of the mines to several residential communities. White Rock Quarries and Krome Quarries are two active mining facilities in South Florida which generate numerous complaints, insurance claims, and lawsuits from residents in nearby communities who claim that the vibrations cause damage to their houses. Both quarries are located on the eastern edge of the Everglades, with thousands of nearby residences at the western edge of development in Broward and Miami-Dade Counties. Data obtained from over 400 publicly available blast monitoring and associated seismograph reports from White Rock Quarries were reviewed and compiled. The data was used to emperically develop a conservative estimate of the ground attenuation rate based on the scaled distance from the blast origin, which can be compared to Figure B-1 from USBM RI 8507 to determine whether it is feasible if damage could have occurred at a given property.

By Paul Worsey, Matthew Coy

In the blasting industry, many different techniques are used to estimate and examine the effects of varying explosives and blast designs on the breakage of a rock mass. The overall objective is to find a cost-minimized blasting solution that also conforms to the legal and environmental concerns related to blasting. A major drawback to current blasting methods is the inability to account for "caprock," or a thick overlying layer found in sedimentary rocks that creates large amounts of oversize blasted material, especially on the top of a muck pile. This can lead to underestimating oversize in shots with massive top layers. A better fundamental understanding of blasting processes with caprock is required.

Jan 1, 2018

By Thad M. Jones

This paper considers the sampling, digitizing and reconstruction of seismic signals. A sampling frequency range is proposed and a minimum limit is suggested. Digitizing precision criteria for both peak velocity and analysis applications are given. Several methods for reconstructing signals from sampled data are presented.

Jan 1, 1985

By Y Wada, Y Ogata, T Nishida

"Shaped charge is used for blast demolition of steel construction in general. It is important tocontrol movement of cutting part with shaped charge for the blast demolition of steel construction.Movement of cutting part was studied in the small scale experiment with steel bar. A numericalsimulation using the Discontinuous Deformation Analysis (DDA) was carried out. The DDAmethod was applied to the full scale blast demolition of steel construction. Results of thesenumerical simulation was compared with the blasting demolition work of steel tower."

Jan 1, 1999

By Benedict C. Di Duca

In the underground construction industry. when bidding work, not only is the contractor faced with determining if rock: is in existence within the parameters of his work. he must also estimate the quantity and the most efficient method of removal.

Jan 1, 1990

By Shuli Teng, Vladimir Sujansky, Matthew Rawls, Ivan Junarsa

In recent years significant advances have been made in chemical processing technology. In particular, process intensification using micro-technology has had some success in changing and improving chemical processes including mixing. Process Intensification is the miniaturization of unit operations and processes whereby a smaller compact piece of equipment takes the place of a larger one at the same given capacity or mass flow rate. This paper summarizes research into the application of the technology for manufacture of high internal phase water in oil ammonium nitrate emulsions (ANE’s) at low energy cost and with very low oil/fuel blend content. The emulsions can be used as precursors for preparation of explosives. The quality of the emulsion prepared was assessed through droplet and crystal analysis and compared with that of emulsions made by conventional large scale jet mixing technology.

Jan 1, 2014

By Thomas Kovalchuk, Kenneth Eltschlager, William Shuss

In April of 2000, two adults and their newborn infant, were poisoned by carbon monoxide in their home and received medical treatment at a Pennsylvania hospital. Carboxyhemoglobin levels were; child - 3 1%, father - 28Oh, and mother - 17%. Initially the furnace was blamed but after further review, blasting at a nearby coal mine was determined to be the source. All other sources of carbon monoxide were ruled out. The blasting was about 400 feet from the house. The conditions that led to the migration of gas include: the blasts were highly confined, the geologic structure contained fractures that served as conduits for the carbon monoxide to reach a hand-dug well outside the house, and the well was atmospherically connected to the basement floor drains.

Jan 1, 2001

By Muamer Medusalic, Kim Henley, Lucas Bottomley

The period from 2009 to 2012 has witnessed a large rise in the number of blast-generated fume events in Eastern Australia, where highly visible oxides of nitrogen (NOx) are produced from coal mine blasting. Fume production mechanisms have been poorly understood by mine operators, and practical measures to reduce fume were initially elusive. Over time, data on fume events has been collected and analysis has pointed to a range of contributing factors associated with fume production.

Jan 1, 2012

By Calvin Konya, Steven S. Spagna, Ed Smith

During Summer 2001, the U.S Army Corps of Engineers awarded a contract to the construction firm of Bush and Burchett of Allen, Kentucky, for the purpose of developing a 13 acre redevelopment site by removing approximately 2.5 million cubic yards of rock (fig. 1). The Redevelopment Site will be the future home for a large portion of the City of Grundy, Virginia. Additional work items include the construction and relocation of 3,000 feet of the Norfolk Southern railroad bed, the placement of 95,000 cubic yards of fill and the placement of 16,000 cubic yards of stone slope protection along the Levisa Fork River. Bush and Burchett received a notice to proceed with construction in July 2001. Currently, the contract is near completion. Current activities include: hauling of material from the Redevelopment Site to the disposal area; placing fill material on the Redevelopment Site, and placing Stone Slope Protection (SSP) along the Levisa Fork river. Approximately one year into the construction highly weathered rock, degraded to near soil- like condition, was encountered in the upstream portion of the excavation. Over one-third of the original cut slope was adjusted and the blasting specifications had to be amended to accommodate for the material that was encountered in this area.

Jan 1, 2005

By H. R. Maggard, C. M. Bollinger

Solving the problem of detecting underwater explosions from "dynamite fishing" can be done by using a system of sonobuoys programmed to detect the acoustic waves from underwater explosions. The system includes three anchored sonobuoys, which have radio communication to a central station. Each sonobuoy will detect the direction the blast occurred, and then send the magnitude of the acoustic waves and the blast direction to the central station where the blast distance will be calculated. The central station can the send the coordinates to the authorities who can find the location using GPS systems onboard their boats.

Jan 1, 2004

By Alastair Torrance

The performance of commercial explosives is clearly influenced by the conditions under which they are used. Mining companies are supplied with Technical Data Sheets which provide details about explosive properties and its suitable application. These are generally produced using laboratory techniques which may not accurately reflect the quality and performance of the product in the field.

Jan 1, 2013

By Ron Woolf, Corry Goumans

This paper describes rock slope remediation performed along America’s first Superhighway, the Pennsylvania Turnpike and in particular, the specialized drilling equipment designed and built by Pacific Blasting to complete this work. This S-month project was performed on an existing rock cut slope within the Bedford Narrows, a gap formed by the Juniata River through Evitts Mountain. These rocks are in the folded Juniata and Tuscarora Formations within the Valley and Ridge Province and strike northeast with near vertical to slightly overturned bedding.

Jan 1, 2001

By Scott Stephenson

Making a tunnel through solid rock can sometimes be a dangerous task. Many things must be considered in order to complete such a task safely, and efficiently. Prior to starting things must be known such as, the type of rock, the purpose for the tunnel, the destination point, then angle of decent (or ascent). Once these things are known, the method to proceed must be considered. Factors such as cost, feasibility, and time to completion must be taken into account.

Jan 1, 2009

By Richard J. Mainiero, Harry C. Verakis, John J. Mulhern

There are application in coal mines where it would be advantageous from a safety stand point to fire unconfined shots. However, the firing of mud caps (adobes) or other unconfined explosive charges in underground coal mines is not permitted because of the explosion hazards associated with methane gas and coal dust. Present safety regulations in Title 30, Code of Federal Regulations prohibit such Practices. Recently, MSHA proposed revised coal mine regulations for the approval and use of sheathed explosives for Public comment.

Jan 1, 1987

By Earl Cook

With all our power and hope, we are part of the natural system and subject to its laws. As Francis Bacon pointed out long ago, we must understand those laws and "obey" them if we wish to "conquer nature." Bacon was saying that if we plan and engineer in compliance with nature's laws, we'll get a lot more out of the natural system than if we don't, because then we can use the system instead of fighting it.

Jan 1, 1979

In this paper, the author points out the need to beware of simple time correlations as proof of cause and effect when comparing building cracks and blasting operations. There is a need to be aware of the many other causes besides blasting which affect buildings. Some of these have histories of cyclic behavior; others have a long-term increasing effect on aging and deterioration, often with poorly defined time histories. Many are so strongly site specific that generic relationships are difficult to quantify.

Jan 1, 1981