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By Alvin D. Christmas

The missing link is a connector between the congested downtown area of Knoxville, Tennessee adjacent to the former World's Fair site, the I_40 I_75, and Western Avenue traffic arteries. This connecter was designed to accommodate the 37,470 motorists who presently travel through these highly congested narrow paths to be replaced by the 21.8 million dollar Henely Street Connecter. All construction and blasting was to take place while existing traffic was re_routed so as to allow access between the downtown area and the vital interstate corridor. To avoid major traffic problems, the project was to be accomplished in three phases: (1) the Western Avenue viaduct demolition; (2) two new viaducts to be constructed; (3) the open box cut at Henely Street next to the L & N Depot. Due to the past attempts by the Fort Sanders Community Home Owners group and the Historical Society to stop the Henely Street Connector, this project involved a very comprehensive blasting damage control program with special provisions of .5 inches per second measured at the foundation of the closest structure.

Jan 1, 1995

By Donald Hurd, James Rowland, Richard Mainiero

In previous conferences the authors have reported on toxic fumes generated by the detonation of ANFO. The research reported here extends the earlier work to include an emulsion blasting agent and ANFO/emulsion blends. Explosive mixtures were shot in 4-inch Schedule 80 steel pipe (outer diameter 4.50 in (11.43 cm), inner diameter 3.83 in (9.72 cm)) in a chamber in the experimental mine at the Pittsburgh Research Laboratory (PRL). Following each shot, the fumes in the chamber were analyzed using on-line instrumentation.

Jan 1, 2001

By Ian Bell, Shahram Tafazoli, Bahram Sameti, Aylin Azmin, Edmond Chow, Nima Ziraknejad

Image-based rock fragmentation analysis methods have been applied by blast engineers to estimate rock size distribution for over 25 years. These methods utilize a wide range of image segmentation techniques, from manual to fully-automated, to delineate the edges of the rocks in the image. In most commercially available image-based rock fragmentation analysis systems, rock delineation results are converted to physical rock sizes by introducing one or more reference objects (e.g., basketballs or other objects with known geometry) to the scene as size-scaling references.

Jan 1, 2014

By Larry D. Lawrence, Gerald W. Greenway

Corrugated boxes have been the dominant shipping container for packaged commercial explosives for the past 3 decades. Recent changes in shipping regulations have dictated to the industry the adoption of enhanced standards dealing with the construction of fiberboard shipping containers for explosives. Effective October 1944, all shipping containers used for explosives will require individual certification verifying that the containers conform to the United Nations performance oriented packaging standards. The U.S. Department of Transportation will continue to enforce compliance to the new UN standards. A renewed emphasis on the design of corrugated shipping containers to insure industry compliance to the UN standards has been a joint development program between the explosive manufacturers, fiberboard container suppliers and the academic community. Along with drop strength, leakproofness, and vibration resistance, the individual stacking strength of corrugated shipping containers has come under tight scrutiny based on the new UN standards.

Jan 1, 1994

By S. S. Jenkins Jr.

While the method is seldom used anymore, coyote blasting is an historically interesting way to blast large quantities of rock. It was used extensively in the days before modern fast drills were available and can be very effective in some formations that have a natural breakage pattern. This paper will cover the general principles, some blast design factors and point out several actual blasts including some very large ones.

Jan 1, 2005

By C. T. Aimone-Martin, V. L. Rosenhaim

Blasting near residential areas has become frequent in many locations throughout Brazil. It was deemed necessary by the authors to have a better understanding of how typical Brazilian structures respond to blast vibrations and compare this response to environmental forces that naturally act on these structures. Typical Brazilian structures are built with clay bricks and cement-mortar. Foundations comprise concrete beam perimeter walls and thin concrete slabs. Roofs are very heavy as they are construction with clay tiles over a wood frame. Typically, walls are cover with cement grout, spackling (or plastered) and then painted. Interior walls are made of clay bricks and mortar to divide in rooms inside the structures.

Jan 1, 2014

By Clay McNail, Paul N. Worsey, John Schillie

"This paper is the result of undergraduate student research over the period of 2 semesters at UMR, which was focussed on developing a practical way to pneumatically stem horizontal boreholes, mostcommonly used underground. The majority of dry horizontal underground boreholes are pneumatically loaded with bulk ANFO. ANFO is preferred due to its low cost and the ease of pneumatic loading. However, stemming underground in the United States is a rare practice. In sharp contrast, stemming material (crushed stone or drill cuttings) is virtually always used in surface holes. The purpose of stemming is to increase blast efficiency by containing the explosive energy in the ground and to reduce environmental effects such as air-blast. The problem with stemming horizontal boreholes are; gravity cannot be used to load stemming material and the ANFO does not have a good interface due to problems with withdrawing the hose and the loading itself. This work follows on from Wilkins’ work on stemming angled boreholes."

Jan 1, 1999

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 Tom Goforth, Rongmao Zhou

The interest of seismologists in mining explosions has increased substantially with the construction of the International Monitoring System (IMS). The IMS supports the Comprehensive Nuclear Test-Ban Treaty by providing global data coverage from seismic, hydro acoustic, infrasonic, and radionuclide sensors that will detect a host of natural and man-made events at regional (<2000 km) distances. Ideally, the recorded data can be used to identify those events that have explosive characteristics and therefore might be clandestine nuclear tests. The regional observations assure the detection of mining explosions, and these must be properly identified to avoid false alarms of the monitoring system. Cooperation with the mining industry, including documentation of the firing programs, provides critical information necessary to characterize the seismograms.

Jan 1, 2006

By Lawrie Logan, Mike Wiggin

This paper will be in two parts, a discussion of the benefits available from benefit sharing as a concept followed by an examination of how this approach was applied at Mesa J Mine and what improvements were made. The first part is an outline of the ways that both parties in a benefit sharing agreement can uncover additional wealth by bringing a new approach to the relationships between mine and supplier. The paper describes a partnering agreement recently established between Robe River Iron Associates (RRIA) and Dyno Nobel Asia Pacific Ltd (DNAP) to access the wealth locked up by the usual explosives supply contracts in Australia and elsewhere. The partners are acting cooperatively to maximise the benefits to both parties from optimising blasting practices at the Mesa J Iron Ore Mine in the Pilbara region of Western Australia.

Jan 1, 2001

By Dan McCutchen, Oettmeier

Kelly bar drilling and blasting is unique to Florida, the' Bahamas and other marine limestone areas in the world where blast holes are required but will not remain open for the loading of explosives. This type of rock formation usually yields 1.5 tons of recoverable rock compared to 2.2 tons per cubic yard for competent limestone. The loss of .7 tons per cubic yard is due to voids and sand in the formation. These deposits all contain water to the top of the blast holes which are collared only a few ft. above the ground water level. The working pit is a water filled lake which is excavated from the bank by draglines. These drills have been used in Florida for many years to depths of 65 ft or less.

Jan 1, 1991

By Florian Bauer

The Fording River mine in British Columbia produces hard coking coal in an open pit operation. Coal seams are exposed by blasting overburden and digging blasted muck with rope shovels. The drilling and blasting process presents a considerable cost factor to the operation. Reducing the amount of explosives needed therefore contributes considerably to costs saving initiatives. However, reducing the powder factor only makes sense if the subsequent loading processes by the shovels are not compromised in terms of productivity.

Jan 1, 2014

By Bryan J. Lane, Paul N. Worsey

The recommended maximum explosive weight for boulder blasting using internal charges is 0.1 O-kg/m” (3.5 oz./yd) (Olofsson, 1988). Normally this charge results in excessive scattering and flyrock, creating increased liability for the operator, especially in congested areas. An alternative technique using smaller explosive charges is being developed at the University of Missouri - Rolla. It is designed to reduce boulder scatter, flyrock and fumes and allows shooting in close proximity, using common blasting products.

Jan 1, 1999

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 Mark S. Rayson, Jessy Lee, David O. Johnson, Matthew R. Rawls

The ability to manipulate the structure of liquid chemicals in an explosive is important in mining applications, where precision blasting is crucial for the safe, reliable, economical and eco-friendly extraction of ores. Static mixers allow explosives, emulsion-based in particular, to be custom-made as they offer precise and reproducible mixing without the need for moving mechanical parts. In this paper, we perform numerical simulations on the laminar mixing of two nitrate-based fluids in a Kenics static mixer unit for various mixer parameters. Two numerical methods were investigated in the study of the mixing pattern: solving the mass transfer equation and using particle tracking. The former introduces artificial numerical diffusion which can lead to spurious smearing of the component boundaries, a problem that can be avoided with the latter technique. We have also demonstrated that the particle tracing method is capable of qualitatively predicting the blending patterns under the conditions studied.

Jan 1, 2014

By Matthew K. Coy, Paul N. Worsey

The work described in this paper comprised the master’s thesis work of the primary author and was conducted at the Missouri S&T experimental mine. The objective was to determine if rubber tractor treads could be used as an alternative material for blasting mats. These treads are made from steel cable and vulcanized rubber and are very tough. However, once they reach the end of their life on mobile equipment, they are destined for a landfill, or dump site, because they are too tough to recycle. A potential alternative use for them is as blasting mats. Several discarded treads were obtained from Kolb Grading in St. Louis.

Jan 1, 2015

By Luiz Felipe Mendonça de Amorim, Adimir Fernando Rezende, Gustavo Sampaio Lopes, Claudio Cesar Gajardo Arraño, Eltton de Sousa Veras, Manuel Villalobos Calderon

Many technical challenges were encountered while conducting near-field construction blasting between the critical intersection of Interstate 10 and multiple active railroad tracks in El Paso, Texas, for the Loop 375 Border West Expressway Project. Blasting was utilized for the removal of an andesite bedrock ridge in preparation for the construction of a new elevated super structure to be suspended over the existing railroad tracks. There was concern that the excessive vibrations and/or permanent rock deformation produced from the blasting within near proximity (20 feet, or 6.09 meters) of the railroad tracks would induce excessive stress and foul the tracks by shifting the alignment. This could result in a major loss of scheduling control between the two major railroad companies that operate in this area. There was also concern that the blasting may cause rock fragments to land on and interfere with critical interstate transportation. Blasts

Jan 1, 2019

By Derek Morris, Vito Saccheri

In the monitoring of seismic exploration (whether by explosive or vibratory energy sources), the intensity of shaking at neighboring structures can now be measured quite accurately and comprehensively with portable equipment. However, the interpretation of the results is open to considerable debate and mis-interpretation. One conventional approach is simply to compare the maximum measured peak particle velocity (PPV) with a permissible standard – usually 0.5 inches/sec (1.3 cm/sec) because this is the value generally referred to in the U.S. Bureau of Mines standard. This can be very conservative, both for surface structures, and especially for buried structures like pipes, for which absolute reliance on PPV obscures the true complexity of field problems. Quite apart from the fact that the full Bureau of Mines standard is actually a reasonably complex function of frequency (for the simple reason that in differing parts of the frequency spectrum, damage may be displacement or acceleration controlled), the effects of spatial direction and orientation are often ignored.

Jan 1, 2009

By P. Ross, O. Rielo, P. Katsabanis

Selection of delay times to optimize fragmentation has been a controversial topic among researchers and blasting practitioners. The paper reviews all available experimental information, ranging from small and medium scale tests in geologic materials to small scale tests at the laboratory and synthetic materials, simulating rock. Tests have been re-analyzed and discussed in terms of the information they present and the limitation of the testing environment in representing actual conditions. New results obtained from blasting experiments in specimens made of a grout have provided a clear picture of the effect of delay on fragmentation. The grout used has a strength of 60 MPa (8700 psi), density of 2.5 g/cm3 and P-wave velocity of 4000 m/s (13100 ft/s). Each block was placed in a yoke to eliminate unwanted reflections and the desired delay was obtained using the appropriate length of detonating cord between holes or sub-millisecond electronic detonators. Delays ranged from 0.1 ms/m (0.03 ms/ft) of burden to 16 ms/m (4.9 ms/ft) of burden. Fragmentation was obtained using screen analysis of the collected fragments. Delay time has been shown to be a significant parameter affecting fragmentation and back break. Generally larger fragments and less back break was observed at short values, while fragmentation somewhat deteriorated at significant delay times, compared to what was observed at intermediate delay times. The work is now extended to include the effect of energy partition on fragmentation as well as the effect of initiation point and coupling ratio.

Jan 1, 2014

By Juan Pablo Guevara, Victor Munoz, Rob Bush, Gonzalo Marias

Cerro Negro Mine, property of Goldcorp Inc., is in the process of developing four separate underground access ramps for the exploitation of high grade, narrow vein gold deposits with vertical to sub-vertical dips. The Mariana Central, Mariana Norte, and San Marcos accesses are primarily in the development stages, while the Eureka access began production stope blasting in April of 2013. Mariana Central will also begin production in May or June of 2014.

Jan 1, 2015