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By Duan Baofu, Wang Xuguang, Song Jinquan

In this paper, the model of optimizing selection on preparation of Powdery Emulsion Explosives(PEE) is established by the Neural Net Theory(NNT). On the basis of some data in the study of PEE, the training, prediction and optimizing selection of the Neural Net (NN) model are finished by a compiling procedure. The results indicate that the model is helpful to the preparation of PEE and worthy to extend and apply broadly. KTYWORDS Neural Net Powdery Emulsion Explosives Preparation Optimizing Selection

Jan 1, 2003

By Gregory Hempen, Thomas Keevin, Russell Wilcox, William Wild

The Department of Defense Strategic Environmental Research & Development Program (SERDP) awarded funding for evaluation of procedures to mitigate peak pressures and energy flux density in the water column from ordnance being detonated on the ocean floor. The research purpose was to conduct scaled testing to resolve whether a theoretically-viable covering technology was operationally effective in reducing blast effects and the impacts of shrapnel. An additional objective was testing effectiveness of this method for hard-bottom units (rock or coral) and (unconsolidated) sediment substrate.

Jan 1, 2011

The following situation was submitted as an ethics case study for inclusion in the Journal. To the best of our knowledge, they are based on actual circumstances encountered in the field. Blowing the Whistle Protecting Confidentiality or Doing the Right Thing? This case centers around a construction job and involves a contractor, subcontractor/blaster, and a farmer/homeowner who lives near the job site. It is essentially a study of professional ethics versus morality, our professional code of conduct versus what is right or wrong.

Jan 1, 2007

By Luis Valentim, Terry Cousins

The goal of a mine is to produce ore at the lowest possible cost with due regard to safety of pemonnel and equipment. The mining process consists of a number of discrete operations such as planning, drilling, blasting,excavation, transportation and crushing. These processes are interrelated and cannot be considered as separate activities when optimising output and minimising cost. In order to optimise the global costs it may therefore be necessary to increase cost in one area such as blasting design and management beyond the norm.

Jan 1, 1998

By Michael Peterson, Robert Davinroy, Robert Rapp, Gregory Hempen, David Herzog, Thomas Keevin

Fish sampling in a deep-water, high velocity, environment is extremely difficult. Conventional techniques such as electro-fishing and netting have been limited to depths generally less than 7 meters (m) and velocities below 1 meter per second (mps). The goal of our study was to sample a bendway weir field on the Mississippi River to assess the effects of the weir field on the fishery. In a bendway weir field, depths can exceed 20 m, and velocities can exceed 3 mps, making conventional sampling techniques inefficient.

Jan 1, 2002

By Shao Li, Chen Zhiming, Wu Jihong

In this paper,powder emulsion explosives,which have high sensitivity and strong detonation force,have been studied by applying emulsion technology to the production of the present powder ones.Under the condition of #8 industrial detonator initiation,the distance of air gap propagation is 110~180mm,brisance !3.5mm, lead block test value 325ml and detonation velocity 3000~4000m/s for small diameter (35mm) explosive cartridges.In addition to these,the factors effect on are investigated by experimental study and theoretical analysis.

Jan 1, 1991

By AN Gupta, N V. Srinivasa Rao

Initiating devices like detonators use sensitive primary explosives. Successful detonation of secondary explosive is achieved by suitable source of energy from primaries. The most widely used primaries contain toxic lead azide and lead styphnate, dinitrodiphenol or tetracine. All these primaries are very sensitive to friction, impact and heat. The handling of these chemicals is very hazardous and many accidents reported in detonator manufacturing were from these primaries only. In addition to this high sensitivity, lead azide and lead styphnate contain lead which is toxic.

Jan 1, 2014

By Lawrence Cheng-Kwang Hu

"Since the only available delay detonator in Taiwan is electric delay detonator, which can beaccidentally initiated by fire, i impact force, friction, static electric, lighting, radiotransmitter, and stray current etc., that always represent fatal threatens to the blasting crew.Fire, impact, friction can be Prevented by handling carefully; lighting also can be detectedwith proper instruments. But when a blaster find an unknown extraneous current in his welllaid down blasting cable; what a horror scence will be expected especially the electricdetonators have been connected already."

Jan 1, 1993

By Douglas Anderson

In the early 1980s, a method for controlling blast vibrations other than by modifying the Scaled Distance came into use. Research studies had indicated that blast vibration could be simulated by detonating a signature hole with the vibration monitored at critical locations, and then using a computer to superpose the waveforms with varying delays. By choosing delay times that create destructive interference at frequencies that are favored by the local geology, the “ringing” vibration that excites structural elements in houses and annoys neighbors could be reduced.

Jan 1, 2008

By R A. Farnfield

Measurement of the environmental impact of ground vibration from blasting operations is based almost exclusively on the peak vibration level generated. This measurement is known as the Peak Particle Velocity or PPV. The recorded PPV is used to assess the impact of the vibration both in terms of structural damage and human response. Limits for vibration are almost universally quoted in terms of PPV levels and, as a consequence, blast design for vibration control is centred around techniques for the control of this peak value.

Jan 1, 1996

By L D. Lawrence, W B. Sudweeks, J Bailey

Modern era urbanization is presenting at least one category of explosive consumers with a growing concern for ecological and environmental problems associated with their blasting processes. The construction industry is now, more than ever, being closely monitored with regard to its use of high explosives. In particular, contractors excavating the countless thousands of miles of various trench lines required for virtually every major new construction development taking place in America are being more closely scrutinized by local, state, and federal authorities with regard to blasting practices.

Jan 1, 1988

By Alex Jankovich, Darren Thornton, Sarrna Kanchibotla, Cam Grundstrom

The Porgera joint venture and Dyno Noble have commissioned a joint project to optimise the drill and blast operations to increase the overall profitability of the mine. One of the aims of this project is to increase the throughput of semi autogenous (sag) mill by optimising the blast fragmentation, The work done so far clearly indicates that significant improvements in sag mill throughput can be achieved by optimizing the blast fragmentation. This paper discusses the planning, implementation and results achieved so far in this project.

Jan 1, 2001

By Tom McDonald, Rodney Burke

As mining progresses in the West, the depth of material has increased, making highwall stability a major factor in safety and production. The Jim Bridger Coal Mine has made highwall stability a priority, concentrating on safety as well as increasing and improving production. Overburden depths are increasing dramatically; the geological environment consists of medium to soft material, faulting, water, and current pit alignment not favorable to joint planes. Angle drilling the presplit at 20 degrees became necessary as vertical presplit drilling produced wall failures.

Jan 1, 1997

By E W. Kohler

Geophysical wireline logging of blastholes provides useful geological data and has considerable potential to improve overall blasting control and costs. This paper uses case histories to show how logging techniques have highlighted certain problems, and discusses the various in-hole tools available. In particular, the issue of the effects of hole diameter on explosive column height,and the importance of this when deck charging is addressed. The suitability and cost-effectiveness of currently available logging technology to the wide range of blasting applications is discussed.

Jan 1, 1988

By Kenneth Eltschlager, Steven V. Crum, David E. Siskind

The Bureau of Mines was funded by the Office of Surface Mining (OSM) to determine how blast vibrations from a local surface coal mine were affecting homes in the towns of Daylight and McCutchanville, located in southwestern Indiana near Evansville. Although Daylight was about two miles from the blasting and McCutchanville four to five miles away, many residents claimed that blast vibrations were damaging their homes. At least one citizen felt that the vibrations worsened at the time the mine began cast blasting.

Jan 1, 1992

By Koichi Kurokawa, Takeo Ueda, Yoji Tasaki, Masashi Nakano

We have developed a new firing system which simplifies the handling and extensively increases the safety in electric blasting operations. Based on the principle of the transformer, this system is operated as follows: When a high frequency alternating current pulse (70-110 kHz) is applied to the lead wire and connecting wire (primary circuit), magnetic flux is generated in the transcore, and an induced current flows through the looped leg wire of the detonator (secondary circuit). Then the detonators are ignited by the induced current.

Jan 1, 1986

By Michael Wieland

Delay blasting in underground coal generates shock waves and rifting forces that damage charges remaining in the blast pattern. Damaged charges detonate poorly, raise fume toxicity and reduce coal breakage. Such circumstances could be prevented by using explosives resistant to cross-hole interaction damage. The design of rugged explosives is fraught with contradictory requirements, but tradeoffs related to hard-particle size characteristics prove useful. Hard particles, related voids or trapped bubbles represent reaction nucleation centers which strongly influence the performance of coal mine explosives.

Jan 1, 1992

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 Y. Idrogo

Electronic delay detonators have been used in most types of blasting application with great success, with the accuracy and precision being used effectively to control negative environmental impacts like vibration. They have also provided consistent repeatable fragmentation and heave results. With the very wide choice in delay period and powerful timing design software, the choice of firing times to optimise blast results is not always clear to the designer. So the improved results achievable from the use of electronic delay detonators are often not optimally achieved.

Jan 1, 2018

By Tom C. Palangio

Commercially available online particle size analyzers (OPSA) are in their third decade of development (Palangio, T.C., 1985), (Franklin, J. A., Maerz, N.H., 1987), (Maerz, N.H., Franklin, J.A., and Coursen, D.L., 1987). The installed base of operating analyzer numbers is in the hundreds. This paper takes a look at five critically important relationships that users have discovered through the use of OPSA systems. The two key attributes of these systems are: 1) consistency and, 2) historical context compared with traditional practices.

Jan 1, 2016