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By John R. Holliday, William Marcum

Apogee Coal Company, DBA Arch of West Virginia, faced the challenge of drilling and blasting over one million cubic yards of high temperature overburden at its Ruffner surface operation near Logan, West Virginia. The overburden was removed above the Upper Five Block seam that was previously deep mined, abandoned, and later engulfed by fire. Borehole temperatures were measured above 700° F.

Jan 1, 1996

By D D. Garg, D A. Wasson

Open pit blasting in India uses two types of explosives. First there are bulk explosives for wet and dry holes, and there are packaged explosives. The Indian open pit coal mining is projected to use 190 thousand metric tons of explosives in 1995. This volume is projected to grow for the next ten years, whereas the underground coal mining will hold fairly constant.

Jan 1, 1995

By Eduardo Berger

This paper describes a mechanized loading system, the HYDRODOSE, which allows the use of pumpable emulsions in underground mining. It also describes a pumpable emulsion explosive for small diameter holes, HYDROMITE PDB. Included are test results carried out in two Chilean underground mines.

Jan 1, 1991

By Kai Nielsen

Drilling and blasting design results in a fragmentation that will have an important economic influence on all subsequent operations such as loading, transport secondary blasting and primary crushing.

Jan 1, 1987

By Donald F. Rapp

Improvements in non-electric initiation systems have given the blasting industry more choices than ever in controlling blast results. By incorporating blasting requirements and system attributes, timing patterns are only limited by the creativity of the shot designer. This paper will discuss the basic groups of non-electric initiation systems, their attributes, and how to select the optimum system for the job.

Jan 1, 1991

By Norman S. Smith, Troy D. Harris, Richard L. Ash

In open-cut bench blasting drilling boreholes below grade level is normally considered essential to insure toes do not remain. The extra drilling and use of explosive below floor level are not only expensive but on occasion cause serious problems including severe floor damage and excessive ground vibrations. It has been reported that under certain circumstances explosive in the subdrilling has been successfully substituted by broken rock with its associated benefits.

Jan 1, 1978

By Jerry Bennett

A recant Bureau of Mines analysis has shown that failure of blast area security systems is the mayor cause of mine blasting accidents. Accidents occur during scheduled blasting because of failure to clear the blast zone, inadequate guarding, and failure of personnel to follow instructions, retreat to a safe location and/or take adequate cover. The high incidence of blastslte security-related accidents could be considerably reduced by increased attention to improving minesite blast-guarding practices.

Jan 1, 1984

By Gerald R. Coonan

Early in the open session of the 1979 SEE Fifth Conference panel discussion, someone asked a question of the panel concerning the future intent of the Office of Surface Mining and the regulatory limits established for ground vibration and air blast. The "gist" of the question was: "What assurances do we have that OSM will not promulgate a limit of 0.5 inch per second ground vibration, or some other number within the next two years or so."

Jan 1, 1979

By George Pittman, Dan McCutchen

When an explosive manufacturer in the USA wants to put a new explosive formula or detonator design in the toughest proving ground in North American, it is Florida. Florida conditions have baffled many creditable blasting experts. This paper deals with some of the methods used to overcome these problems.

Jan 1, 1995

By Zhang Shixun, Wang Xuguang, Zhong Yinting

The Mongol-Russian Joint Mining and Processing Cu-Mo Corporation Erdenet signed a contract with BGRIMM for building a plant to produce 10,000 t/y multitype emulsion explosives by using BGRIMM emulsion explosives manufacturing technology. In order to ensure the realization this contract, we have done a series of studies on the design of technological process and the selection, layout of the production equipment, and made a success.

Jan 1, 1997

By He Guangyi, Han Zhilong

This paper introduces the new technology of deep-hole blasting with water-soil mixed stemming to exposed stonework. Nine aspects of advantages are drawn in the paper based on tests of different types of charge and stemming under the conditions of different geology, height of bench and diameter of drill.

Jan 1, 1998

By Paul Downing

A major component of an effective blasting company safety program is the self-audit. A self-audit can help reveal hazardous conditions that should be corrected and training needs that should be addressed before accidents occur, insurance claims are filed, and/or fines are levied. Such audits, when they lead to appropriate corrective action, can provide significant economic benefits for employers by reducing the costs associated with insurance claims, accidents, and injuries.

Jan 1, 2001

By Feng Shuyu Yang Nianhua

According to the results of high speed photography tests, particle velocity measurement tests and the digital calculation with TP2 software, the shape of shock wave, the declined laws of the shock wave propagation speed and the peak particle velocity are described and analyzed in detail. New viewpoints about the theories of blasting fragmentation based on analysis of the progressive pictures of the fracture region are given. The formula for calculating the depth of fracture regions is established on the basis of the new viewpoints.

Jan 1, 1997

By J T. Keim

Members and guests of the Society of Explosive Engineers, it's indeed a pleasure for a longtime practical user such as myself to have the ears of so many explosive experts for a few minutes just to express my feelings and concerns on blasting as well as the feelings and concerns of many other users and operators.

Jan 1, 1978

By G Dean Barrett, Ed Jr Smith, Calvin J. Konya

The purpose of the project was two fold: 1. To determine whether Pyrodex, a propellant, manufactured by the Hodgdon Powder Company, could be used as a substitute for high explosives for presplitting in granite and other materials. 2. To determine if Pyrodex, a slow reacting propellant which produces no stress waves in rock because it reacts subsonically, could cause the rock to crack similar to the results achieved with high explosives.

Jan 1, 1986

By Kazuyoshi Kawami, Fumihiko Sumiya, Kunihisa Katsuyama, Yuji Ogata, Koichi Kurokawa, Yuji Wada

When explosives are detonated in the borehole where there is an air gap between the explosive charge and the borehole of inner wall, the shock cave in an air gap travelling ahead of the detonation front sill be generated. This shock wave is called the precursor air shock wave (PAS). The explosive is precompressed by the PAS, and as a result of that the detonation failure occur on occasion. This phenomenon is well known as channel effect.

Jan 1, 1994

By Jack Eloranta

Proper selection of stemming has a profound effect on blast performance. This paper describes several methods of evaluating stemming performance in 16-inch blastholes. Tests are done on stemming ranging in size from nominal 1/4" crushed rock up to railroad ballast size rock (2 1/2" > diameter < 3/4"). Concrete plugs (both pre-cast and poured) are evaluated as well as air decking.

Jan 1, 1994

By Randall M. Wheeler

Computer analyses of single hole signatures are often used to help blasting operators predict the type of ground vibration effects that may be produced from production blasts incorporating various delay intervals. Frequency analyses of single hole waveforms and subsequent multi-hole waveform simulations can allow an operator to determine the best type of delay intervals to use in order to minimize low frequency ground vibrations.

Jan 1, 1989

By Trevor Garbutt, Peter Bellairs, Jason Sander, Glenn Shaw

The Yarrie Iron Ore mine is located in the Pilbara region of Western Australia some 200km eastsoutheast of Port Hedland, the closest large regional centre. The mine is owned by BHPIO who has contracted a large Australian mining contractor Roche Bros to be responsible for the total mining, crushing and trainloading functions. This paper describes a drill and blast optimisation program, resulting from the introduction of a new emulsion matrix called Titan@ Red used to manufacture both HANFO and pumped emulsion ANFO blends.

Jan 1, 1999

By J P. F Warkentin, A W. Bauer

Recently, significant improvements have been made in both blast design methods and blasting accessories. The introduction of extremely accurate blast delays now allows proper implementation of advanced blast designs. Thus the onus for future blasting improvements has moved from blast design to the need for ensuring that explosives quality is of the highest order. One measurement commonly used to assess explosive performance is the velocity of detonation (VOD).

Jan 1, 1991