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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 Tom Donnelly, Roger C. Ilsley

Remote telecommunications seismographs were used to monitor blast vibrations at two historic structures in Cedarburg, Wisconsin during adjacent sewer line construction. The purpose of the vibration monitoring program at the historic structures was to maintain blast vibrations below limiting tolerances established by the Wisconsin State Historic Society.

Jan 1, 1991

By Syed M. Tariq, John W. Wilson, Paul N. Worsey

The position of a major joint in relation to a blasthole has a significant effect in presplitting. Broad research into the combined effects of firing two decoupled blastholes has been performed in the past. The effects of joints simulated between two blastholes has also been evaluated. However, no attempt has been made to investigate the splitting effects produced by firing a single decoupled blasthole. This paper presents the results of such an investigation.

Jan 1, 1996

By R J. Roach, D Roy

After months of discussion on ways and means to improve productivity in the shaft sinking process, it was decided to look at those areas where, historically, methods have been stagnant for many years. These categories included drilling, hole diameter, drill patterns, explosive types, explosive loads, initiation techniques, cut design, wall control, fragmentation and heated magazines.

Jan 1, 1997

By Thomas P. Dowling

Since the 1950's, blasting practices have undergone many revolutionary changes. Some of the more radical departures have involved, in addition to high speed drilling equipment, a myriad of new explosives, blasting agents, boosters, initiators, initiating systems and delay devices. The introduction of ANFO in the mid 1950's as a blasting agent seems to have instigated a trend toward the development and use of less sensitive blasting agents. The evolution of slurries or water gels has produced dense, high strength, water resistant products which has further promoted this trend away from the more sensitive, conventional explosives.

Jan 1, 1975

By John J. Barnes

The advent of more powerful explosives, increased bench heights, and larger diameter blastholes has necessitated the use of presplitting techniques in sub-bituminous coal mines. The combination of these factors has increased the energy concentration during blasting, producing severe overbreak problems in the final pit walls. Presplitting with large diameter blastholes has proven to be the most viable method of reducing back break in sub-bituminous coal mines.

Jan 1, 1988

By Brent Blanchard

An emergency demolition project related to a bizarre plane crash has reportedly set a new world record for the tallest structure ever explosively demolished. On Sunday, April 22, 2001, 38-year old Gilbert Paquette was killed when his singleengine Cessna 150 struck a 1,217-foot tall communications transmission tower while flying in heavy fog over a remote region of upper Quebec Province.

Jan 1, 2002

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 Jeffrey A. Straw, Joseph P. Jr Shinko

Ground vibration produced by blasting operations within South Florida, due to saturated soil conditions, generates surface vibration waves that may be measurable over distances of 3 - 5 miles from the source, and perceptible at distances of up to 2 miles. Structures above ground usually receive the most of the attention from the effects of high vibration levels. During construction of the Trilogy Development of the Swerdlow Companies, blasting was completed in a lake excavation immediately adjacent to the City of Pembroke Pines Utility Department, Deep Injection Wells No. 1 and No. 2.

Jan 1, 1994

By Gerald R. Coonan

I'm really here to talk about my pet subject of government relations. I've been in Peabody's Environmental Quality Department, working on regulations, for over five years, and I have seen a number of individuals in the coal industry who were completely stunned when a new regulation was brought to their attention. Their first reaction was, "where did this come from"?

Jan 1, 1980

By Ken C. Pruss

Seismic studies have proven that the frequency with which shock or vibration waves are reacting on a structure, in correlation with the amplitude of those waves, has a definite affect of structural damage. Different structures will react to different frequencies. In the past few years, some major coal producers in the midwest United States have shown that with the use of highly accurate detonators and exotic timing patterns they have effectively been able to adjust frequencies and this has enabled the operators to continue their excavation of overburden in environmentally sensitive areas.

Jan 1, 1989

By Charles R. Welch, Charles E. Joachim

Underwater blasting causes not only ground shock but water-shock. Underwater shock attenuates less with range from the explosive source than ground shock and has the potential for killing fish or marine mammals or for damaging marine structures. The collapse and subsequent oscillation of the gas cavity surrounding the detonation can sometimes produce a greater impulse than the initial shock wave from the detonation. The airblast from underwater detonations can range from nuisance levels to damaging levels.

Jan 1, 1997

By James Barker, David Leidel, Don Crawford, Daniel Dorffer

This paper describes the test processes performed to ensure the suitability of an RF-safe detonator for use in oilfield explosives operations on land and offshore locations where RF silence cannot be implemented or the distances from explosive systems arming operations to the RF source or sources are too close for conventional resistorized hot-wire detonators based on the safe distance tables. The test program for the detonator assembly was based on MIL-STD-461E, “Requirements for the Control of Electromagnetic Interference Characteristics of Subsystems and Equipment”, 20 August 19991.

Jan 1, 2008

By E Emery Gray, Gary Ard

Each year when hundreds of Engineers and Specialists in the explosives industry meet for the SEE Annual Conference, new ideas are exchanged and new business relationships formed. Harbert Construction Corp. and EGA, Inc., a company specializing in drilling and bIasting, formed such a relationship through mutual interest in such a manner.

Jan 1, 1981

By Bill Romanchuk, Real Doucet

Suncor Inc. has been operating the first commercial tarsand open pit mine in the world since 1967. Drilling and blasting operations are required to facilitate overburden removal and tarsand mining by bucketwheel excavators.

Jan 1, 1985

By Eugene Baker

President George Bush signed the Safe Explosives Act (SEA), which amended the Organized Crime Control Act (OCCA) of 1970, into Law on November 24, 2002. As a result of this legislation, new restrictions on who could legally receive or possess explosives in the United States went into effect, resulting in a profound impact on the commercial explosives industry. The law went into effect in two key phases. The first phase, which went into effect on January 24, 2003, resulted in additions to the categories of persons who are prohibited from receiving or possessing explosive materials in the U.S.

Jan 1, 2004

By Winfried Rosenstock

Following successful trials at Chuquicamata / Chile from February to May 2000 and from February 2001 onwards at Burton Coal Mine, RAG International/Thiess Pty Ltd., Queensland / Australia a significant advancement in blasting technology was achieved using electronic detonators. The mine now uses electronic intiation for the majority of overburden blasting.

Jan 1, 2002

By Jerry R. Wallace

This project consisted of blasting for expansion of a major interstate natural gas transmission pipeline pump station. The pump station handled 400-500 million cubic feet (11-14 million cubic meters) of gas per day.

Jan 1, 1996

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 Anne Charline Sauvage

Blast designers and blasters need to know the rock mass influence on blast to increase explosive effi-ciency and to optimize costs, but also to succeed in limiting blast emissions (vibration, overpressure, flyrock) This paper presents an applied approach which makes it possible to structure the information con-cerning the rock mass and the blasting.

Jan 1, 2013