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By J L. Jethwa, A G. Gaithankar

The paper deals with a software method developed to design the optimum blast parameters for tunnels and mine roadways for a given set of geo-mining condition without any major discontinuity. The application of the software is presently limited to 8 D-ahaped excavation where inclined hole cut or four-section parallel cut is used with smooth blasting technique.

Jan 1, 1993

By Patricia Mendoza Watson, Lundquist Robert G

The velocity with which the burden moves after blasting is of concern for safety and economic reasons. Models developed for motion velocity by various researchers were reviewed and likely model parameters were used to develop statistically significant models. Regression analysis and residual analysis were used to determine the model coefficients and the accuracy of the models.

Jan 1, 1990

By Josh Campbell

Modern blast engineering involves the use of modern technology to provide more efficient blasts. Through the use of improved measurement techniques more information can be obtained on many of the physical variables of a quarry rock face. By employing this information, a more efficient production shot can be designed and loaded. Along with improvements in production, greater safety and improved environmental impact can be achieved. This paper concerns the employment of modern blast engineering at a granite quarry in the Southeastern United States. The test period extended over a period of approximately six months, and this paper will show the results achieved in that time span.

Jan 1, 1998

By Jeffrey E. Loney, Andrew F. McKnown

Recovery of contaminated groundwater migrating through bedrock can be very difficult due to the low transmissivity of many bedrock fracture systems. To overcome these difficulties, a system of controlled "trench" blasting has been used on several projects to assist in cutting off and collecting groundwater plumes in bedrock. By using a combination of trench blasting and presplitting techniques, linear "fracture" zones are created in appropriate locations to significantly increase flow into recovery wells and control plume migration.

Jan 1, 1995

By Michael J. Burrell

Sands Hill Coal, located in Wellston, Ohio produces coal for steam generation and crushed limestone for the aggregate market in southeastern Ohio. This paper concerns the blasting and production of the limestone which lies between the #5 and #4 coal seams. The limestone bed averages 8 to 10 feet in thickness and is overlain with 17 to 20 feet of shale from the floor of the #5 seam.

Jan 1, 1990

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 Christoper J. Hunter, Tony Mansel, Carl Kolada

With a current trend toward Bulk Mining methods utilizing both large diameter uphole and downhole drilling, corresponding loading equipment and technology is required to safely and efficiently load these blastholes. Such is the case at Inco Limited Thompson Mine.

Jan 1, 1990

By Qingshou Chen, Gongbo Li, Hengqian Ran

A method for safe fracture of rock, concrete and other brittle solid material using dynamic water pressure by explosion is provided. The propagation of the pressure is studied with Allievi water hammer theory. Wave equation and velocity formulas of the pressure propagation are shown. The dynamic water pressure is tested in the lab. The propagation of the pressure is simulated by MMIC-2D. The results of fracturing rock in the lab and on a quarry are presented.

Jan 1, 2000

By James E. Jr Hargroves

With the ever-increasing population growth and modern trend to urban development, the expansion of utilities is a stable, mad or, and constant source of income for many. Blasting is a "necessary evil" to the utility contractor. It can make or break even the most solvent. Housing development expansion and higher treatment of effluents are causing utilities to appear in more congested areas. This paper discusses some of the aspects of utility blasting in the State of Virginia. Consideration is given to bid procedures, pre-blast surveys, record-keeping and practical application.

Jan 1, 1977

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 Yuji: Wada Ogata, Kunihisa Katsuyama

It is well known that a compressed stress wave reflects at the free face, it propagates to the backward as a tensile stress wave, and cracks grow when the tensile stress becomes the dynamic tensile strength. The behavior of these cracks has been discussed through the observation of the dynamic photoelastic high speed photography.

Jan 1, 1993

By Scott Giltner, Allan Koski

Blasting is one of the lowest cost yet most critical parts of the mining cycle. This paper discusses the findings of an audit conducted on the blasting operation at an iron ore mine. The purpose of the audit was to review current blasting practices in order to identify opportunities for production/cost improvements. The approach taken in the audit was to observe general blasting practices, their related downstream effects and to compare current procedures to established best practices.

Jan 1, 2009

By Paul Worsey, Larry Kenchel, David Randall, Mark Schmidt

The University of Missouri-Rolla (UMR) has historically maintained a manual, paper inventory of explosives stored and used at the university. Although this system was accurate for inventory control and reporting criteria, it was labor intense and delays in record keeping were predominant. A directive from the university’s administration mandated the development of a precise real time system “on-line” to maintain and control the explosives inventory in line with the universities new chemical tracking policies.

Jan 1, 2001

By G E. Exedaktylos, Y Zhou

The complex and non-linear nature of blast fracturing has restricted common bract design primarily to empirical approaches. The code developed for this investigation simulates the pattern of interacting radial fractures from an array of blastholes, at various burdens and spacings, and in simultaneous and delayed modes. The resultant pattern is analyzed and a fragment adze distribution calculated.

Jan 1, 1989

By J S. Brower

Disposing of the AMDP-1, Jackup drilling rig in the Arabian Gulf.

Jan 1, 1978

By John Turner, James Lamb

The Minnesota Department of Transportation (MNDOT) has an extensive project to improve driving conditions and reduce hazards to motorists on US Highway 61 between Duluth, MN, and Canada along the north shore of Lake Superior. In 1991, the Lafayette Bluff Tunnel was completed just north of Two Harbors, MN, through a joint venture of Johnson Brothers Corporation of Litchfield, MN, and Obayashi Corporation of San Francisco, CA.

Jan 1, 1994

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 C H. Ryu

This paper presents a simplified two-dimensional numerical model of block fragmentation in a Jointed rock mass during the late or throw stage of a blast after wave effects have subsided. The model is based on the distinct element method. Examples illustrate the approach and allow for a comparison of effects of Joint patterns on fragmentation and resulting block motion.

Jan 1, 1986

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 E Emery Jr Gray

A need for more delay periods other than those normally manufactured throughout the explosives industry rarely occurs. This paper will discuss one such incident from an analytical view through practical application.

Jan 1, 1976