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By Jerome S. Brower

Quadrex-L is a two component liquid explosive which was developed by J. S. Brower & Associates, Inc. to facilitate handling and shipping, and use in unique applications, while emphasizing safety. It may be advantageously used for all explosive applications. Quadrex-L can be introduced into a preinstalled container configuration and may be easily drained or flushed from these containers when necessary to do so. This characteristic can be effectively utilized to reduce the hazard period during assembly or disassembly operations.

Jan 1, 1975

By G Alan Foster

Because of the marked human response to blast effects and inherent defects present in many modern structures the real possibility of being named as a defendant in a law suit faces most blasters. Until recently even frivolous law suits involved a great deal of expense since legal costs were inevitably incurred whilst waiting for your day in court, which typically occurred some 2-4 years after the alleged damage took place.

Jan 1, 1989

By A Lance McAnuff, Andrew Curic

Until relatively recently, underwater blasting operations for channel deepening, dock construction and pipeline crossings of lakes, rivers and streams were conducted without much regard for the potential side-effects on aquatic organisms.

Jan 1, 1997

By Marlyn G. King, Robert L. Martin

Blasting activities in all four pits at Thunder Basin Coal's Black Thunder Mine are focused on cast blasting. With widths varying from 190 feet to 265 feet and bench heights varying from 90 feet to 175 feet, casting efficiencies vary with different geometry's. For example, the percent cast to final in the 200 foot pit is on the average higher than the 270 foot pit. The powder factors are somewhat higher in the narrower pits, thus increasing the cost of blasting. This leads to a very detailed look at the actual benefit of cast blasting and the associated cost of these benefits.

Jan 1, 1995

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 G Alan Foster

This paper discusses the cause of air blast and modern techniques to reduce this at the source. In addition it raises the problem of their marked variability due to prevailing weather conditions and how weather data can be obtained and used in the control of air blast.

Jan 1, 1975

By R Keller, R Law

In the rush to beat the clock before the handover of Hong Kong back to China in June of 1997, an unprecedented amount of infrastructure work is being undertaken at a breakneck pace. In the middle of this construction explosion, on this island of barren granite , stands some of the most concerning and restrictive slope stability measures. So conservative, these measures impact blasting and vibration control to an extent unmatched anywhere in the world.

Jan 1, 1996

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 Jim Davis, Calvin J. Konya

The methods used to confine the gases within a borehole can influence the amount of useful energy obtained from the explosive charge. Improper confinement not only wastes energy and raises cost but also can result in airblast, excessive ground vibration, flyrock and boulders. The type of stemming material and amount of stemming used will definitely influence the degree of confinement and the efficiency of the blast. In order to extract the maximum energy from the expanding gases, the stemming plug should never blow out and allow the gases to escape prematurely.

Jan 1, 1978

By David A. Smith, B L. Jr Lindsey

Arkansas bauxite varies enormously in its consistency and composition which makes blasting a very difficult operation. Blasting rounds have to be designed based on each particular mine's ore characteristics. The variances are so great in some mines that blasting procedures have to be changed almost daily.

Jan 1, 1979

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 Robert L. Brooks

Blasting liability problems are frequently compounded by a company's inability to effectively communicate with concerned property owners and the lack of adequate complaint documentation. Often, by the time the insurance carrier becomes involved in a blasting claim, the situation has deteriorated to the point that a solution agreeable to both parties is virtually impossible to reach. The insurance carrier, wishing to minimize their lose potential may decide to pay on a somewhat questionable blasting claim rather than be drawn into lengthy civil proceedings that would ultimately end up in front of a jury with little chance for a successful outcome.

Jan 1, 1992

By Wang Xuguang Shen Yingfeng

Structure is the main aspect affecting the performance of emulsion explosive. Calculation of such structure parameters as osmosis pressure, interface area per unit volume etc. must be helpful to the understanding of the structure of emulsion explosive. This paper has solved the Laplace-Young Equation for simplified monodisperse emulsion system by Galerkin method, and gained the relationship between mean curvature, contact angle, volume fraction, fractional film area and interface area per unit volume. The paper also presents a new expression of osmosis pressure at non zero contact angle.

Jan 1, 1998

By Curtis Garner

Griesemer Stone located in Springfield, Missouri has supplied aggregate in Southwest Missouri since 1946. In 1954 the decision was made to mine the formation and utilize the mined out area for warehouse space. As advancement proceeded, entrances and small diameter air shafts for ventilation were needed and had to be added. It was decided in 1989 to sink an 8' diameter air shaft designed to move 200,000 cubic feet of air per minute with the help of (4) four 50,000 CFM Loren Cook Fans.

Jan 1, 1991

By Adrian J. Moore, Alan B. Richards, Rob Evans

Air and ground vibration from blasting is influenced by the delay pattern that is used. Wavefronts from blastholes fired in a blasting pattern can combine in certain circumstances to give increased blast vibration levels. A simple computer model has been developed which shows the combined effect of wavefronts from a multi-hole blast and identifies if wavefront reinforcement occurs, and permits delay patterns to be designed which will avoid or reduce wavefront reinforcement.

Jan 1, 1994

By Ed Jr Smith, Calvin J. Konya

The purpose of this paper is to describe the case history of a blasting project conducted jointly by Precision Blasting Services and Cherokee Explosives. It is the intent of the authors to show how blasting could be done in controlled fashion near very expensive computer controlled machinery. The job was done in minimal time with no complaints or allegations of damage in spite of the fact that blasting was conducted within five feet of the equipment and with the 32 acre plant fully operational, with machine operators working within 10 feet of the blasting site.

Jan 1, 1986

By J S. Kuszmaul

The economic development of modified in situ oil shale retorting will benefit from the ability to design a blasting scheme that creates a rubble bed of uniform permeability. Preparing such a design depends upon successfully predicting how a given explosive will break rock. Numerical models are used to make predictions of the extent of damage caused by an explosion.

Jan 1, 1985

By Carl R. Peterson, Robert G. Lundquist

The development of a remotely-controlled drill and blast excavation system is desirable both because it is potentially more economical than mechanical tunneling in hard rock and for safety. A serious impediment to such development is the problem of relocating and reentering previously drilled blast holes to place the explosives.

Jan 1, 1983

By William Yutmeyer, Meredith Hardwick

Since 1996 there have been at least two teams formed within the U.S. Government to develop a consistent set of risk-based standards to be used to govern safety. The first of these was the Risk and Lethality Commonality Team which developed risk criteria associated with protecting personnel during launches at the national test ranges. The second team titled the Risk-Based Explosives Safety Criteria Team (RBESCT) is the subject of this paper.

Jan 1, 2007

By Steven V. Crum, David E. Siskind

In response to its own concerns and those of the public, industry and regulatory agencies, the Bureau of Mines is studying the impacts of low-frequency blast vibrations on structures. Previous research has identified potential problems associated with low-frequency ground vibrations and also found that their existence was not particularly rare, given large surface mine blasts and certain geologic conditions. Only a limited amount of data existed in the blast vibration literature on structure response to ground-vibration frequencies below 6 Hz.

Jan 1, 1993