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By Young-Dong Cho, Han-uk Lim, Bok-Ki Park, Sang-Eun Lee

Many methods and techniques have been developed to reduce ground vibrations. Some of them are an adoption of electric millisecond detonators with a sequential blasting machine and an improvement of initiating system with an adequate number of delay intevals.

Jan 1, 1995

By R J. Hill

Blasters are well aware of the problems and expense faced when trying to load in wet bore holes; problems of poor coupling and poor density, as well as the expense of higher priced cartridge product. In answer to these problems, I developed a system for dewatering using nozzles with lay -flat plastic liners which I have used successfully over the last few years. I found the system not only gave me better shots than I could have expected in the circumstances, but also dramatically decreased costs. The system has been adopted by two large roading contractors and a quarry operation in Eastern Canada.

Jan 1, 1986

By Robert B. Hopler

The Hercudet™ non-electric delay blasting cap system has exhibited outstanding performance and economic results in surface work. The versatility inherent in the system, which allows the combining of the built-in cap delays with the tubing delay (i.e.: the travel time of the gas reaction through the tubing), has resulted in outstanding blast results. Examples of blast patterns used, details of the blast design process, and recently-developed methods of use of Hercudet for surface initiation of detonating cord downlines are given in the paper.

Jan 1, 1978

By Gungor Tuncer, Erhan Bakirci, Ali Kahriman, Atilla Ozmen, O. Nuri Ucan, Savas Gorgun

There are several methods for demolition of structures but most of them depend mostly on conventional ways of using machines for breaking and crushing structural elements. However the need for lots of work force, expense and extreme amount of time for demolition, made most of these methods non-popular nowadays. Therefore, trials to accomplish a more economic and less time taking method lasted with the use of blasting. By applying controlled blasting on a suitable structure, the structure can collapse and break down to pieces in very short period of time, with no extra work force and cost. In spite of advantages of explosive demolition, the potential danger of explosives and the damage that the blasting may cause to surrondings, if not controlled properly, made people timid to the method especially in urban areas. Therefore, the pre-assumption by computational analysis has become an essential matter in the process.

Jan 1, 2002

By Philip M. E Thomas

For over sixty years man has struggled to defeat the natural swamp lands known as the Florida Everglades as demand for land to support the burgeoning population growth in the state continued almost unchecked. Over the past ten years there has been a growing awareness that this land development could wipe out a whole ecosystem in a very short time unless steps were taken to reverse the trends. In 1991, a state law called the Marjory Stoneman Douglas Everglades Protection Act was enacted giving power to the South Florida Water Management Board to condemn certain lands for conversion to manmade swamp lands, designed to filter polluting run-off water from the agricultural lands around Lake Ockeechobee.

Jan 1, 1994

By Mark S. Stagg, Siskind David E

The mining industry occasionally blasts near pressurized transmission pipelines and has requested guidance on safe vibration levels and setback distances. The Bureau of Mines and the Indiana Department of Natural Resources cooperated with AMAX Coal Company on a study of coal mine overburden blasting. Five buried and pressurized 250-ft pipeline sections were specifically installed on the Minnehaha Mine highwall near Sullivan, IN for testing to failure. Four welded steel pipes ranging from 6- to 20-in diameter and one 8-in PVC water supply pipe were monitored for vibration, strain, and internal pressure for a period of 6 months while production blasting advanced up to the pipeline field. In contrast to previous studies of small-scale blasting representing construction activities, these tests involved overburden blasts of up to 2100 lb per delay in 12-1/4-in diameter holes.

Jan 1, 1993

By Robert Hopler

Complying with our request in the February issue of the AGRICULTURAL BLASTER for items that would be of interest to other blasters, Mr. Thomas H. Benton of Tennessee sends us an article in which his methods of securing contracts are explained:

Jan 1, 2013

By Virgil J. Stachura, Calvin L. Cumerlato

The Bureau of Mines conducted a series of tests to develop a blasting method that would reduce overbreak and rockfall hazards at a limestone quarry in northeastern Wisconsin. Reductions in overbreak were achieved by shortening the main explosive column and reducing the explosive load in shortened stemming zones in shotholes which were to form the highwalls. Two blasthole diameters, 3 and 4 inches, were used with 7 by 7 foot and 9 by 12 foot burdens and spacings respectively. ANFO, Comsol 300, or PowerAN were used in the body of the shots and Gelmax or 40 pct extra dynamite cartridges were used in the reduced load zones. Smoother highwalls were visually apparent, however further analysis by seismic refraction techniques were performed as an aid to studying overbreak within the rock mass.

Jan 1, 1989

By Ali Kahriman

This paper presents the results of ground vibration and air blast measurements from tunnel blasting activities during the construction of the Beylerbeyi-Kucuksu waste water tunnel under a residential area in Istanbul, Turkey. Within the scope of the study, the blasting pattern of the tunnel was engineered using Tunnel2000 design software and field studies and measurements for evaluating the productivity and safety of shots were realized for 136 rounds. During the study, the advance of the tunnel, face condition, ground vibration, air blast and neighbours’ complains and comments after every round were observed and the tunnel pattern was improved. Finally, an empirical relation for this tunnel route was developed between scaled distance and maximum amount of explosives, to continue activities in a safe and productive manner.

Jan 1, 2006

By D O. Tan Sky

This paper will describe the mechanisms involved in delay blasting and how they are applied with the use of D.S.B. It will examine the control of potential damage resulting from detonations, and show how good fragmentation and efficient recovery of this material blasted can be achieved.

Jan 1, 1980

By Zuhair Ibrahim, Dan Tillema, Ali Reza

This paper details the investigation of a fatal explosion that occurred on April 8, 2011 at a magazine used to store fireworks in Waikele, HI. The fireworks had been confiscated by the Bureau of Immigrations and Customs Enforcement after they were informed that a container shipped to the United States contained illegal fireworks. Four groups of cardboard cartons that were marked as 1.4G (consumer fireworks) were determined to be consistent with the more explosive 1.3G type, commercial display fireworks. The subcontractor retained to destroy these fireworks stored the shipment in the subject magazine and was in the process of disassembling them on the day the explosion occurred.

Jan 1, 2014

By Thomas H. Kleine, Alan R. Cameron, William W. Forsyth

In general the software required by a blast designer includes tools that graphically present blast designs (surface & underground), can analyze a design or predict its result, and can assess blasting results. As computers develop and computer literacy continues to rise the development of and use of such tools will spread.

Jan 1, 1995

By Shawn Kirkpatrick, Yang Ruilin, Tamara Whitaker

In order to manage blast vibration in soft ground containing large diameter holes and large charge weights, a number of issues must be considered. This paper describes techniques to control and reduce near-field blast vibrations absorbed by highwalls in soft ground. Sympathetic detonations need to be controlled. Sympathetic detonations can cause excessive vibration due to an unknown number of charge weights firing out of sequence. The excessive vibration can cause damage to the ground. Sympathetic detonations can be controlled through proper design of blast patterns and, in some cases, through the use of specialized electronic detonators.

Jan 1, 2009

By Andrew F. McKown

This paper will discuss the mechanisms of potential damage from close-in construction blasting, concentrating on two mechanisms: elastic ground vibrations and non-elastic (permanent) ground deformations. The latter will be shown to be the most dangerous for close-in blasting. With respect to elastic ground vibrations, discussion will center on the differences in vibration frequencies and impacts between typical close-in construction blasting and typical mine and quarry blasts, and how using vibration criteria derived for residential structures near mines can lead to very conservative criteria for close-in construction blasting. The effects of high frequency vibrations seen in close-in blasting will be commented on. Factors affecting the magnitude of ground motions will be discussed. Simple, practical techniques will be presented to minimize the potential for damage from close-in blasting, by minimizing the potential for rock block movement or ground heave. Case histories will be presented to illustrate some of the techniques discussed, and give examples of successful close-in blasting projects.

Jan 1, 1991

By Leslie Taylor, W. L. Fourney, Uli Leiste

Over the past few years, our laboratory has been investigating the loading on vehicles due to the detonation of buried explosives. We have been using target plates to represent the bottom of the vehicles that were being subject to the forces from the detonating explosives. Parameters shown to be important in the blast loading were type of soil, stand off distance (distance from the surface of the soil to the bottom of the target plate), and depth of burial (distance of the charge center of gravity to the sand surface). We conducted over the first year of our work a large number of tests which looked at the impulse being applied to the plates as a function of depth of burial, stand off distance, and type of soil. Of the three parameters we found stand off distance to be most important, depth of burial to be the next most important parameter, with type of soil least important. We also found that impulse could be scaled with explosive size quite accurately and that results (for impulse) were quite repeatable from one test to the next.

Jan 1, 2008

By N K. Jain, Rajesh Jain

This article has been written indicating the present trend in Blasting all over the World, so as to help in planning production and development of Industrial Explosives for the development of industries in all the countries in general

Jan 1, 1992

By Jerry R. Wallace

Infrastructure improvements and industrial plant expansion and modernization often require rock blasting within 20 feet of existing structures. In many instances trenchlines must cross beneath existing in-serv1ce utility lines.

Jan 1, 1994

By Paul D. Dupree

This paper discusses the drilling and blasting techniques used in blast casting at a large western coal stripping operation.

Jan 1, 1986

By Mark Bauckman

Discussion Topics • Market Needs • Technology Developments & Best Practices • Industry & Government Developments • Future Possibilities & Your Role

Jan 1, 2006

By Heins Walter Wild

Detailed investigations on various configuration kinds of cut with respect to drilling-technological and blasting-technological properties as well as with respect to cost effectiveness have been carried out in Germany.

Jan 1, 1995