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Lightning Strikes on Vehicles Transporting Explosives The police in one of the countries in which we operate has asked about the consequences of a lightning strike on a vehicle (box van) carrying detonators and explosives. We have assured them that there is not a problem but they require proof of this.

Jan 1, 2011

By B H. A Brown

The components of passive laser survey systems and their relative functions are presented. A general outline of the capabilities and the information available are followed by two case histories. These involve the use of such systems in quarry blasts where loading adjustments and drilling designs were required. Their application in blast casting operations, stockpile measurement, surface and underground construction, and general surveying areas are briefly covered, with comments on the potential for demonstrating a return on an investment in laser survey equipment.

Jan 1, 1990

By Kfw Eick

The paper describes the use of the Nonel millisecond delay blasting system in narrow, deep, tabular ore bodies and briefly describes the standard stoping method as used on Harmony Gold Mine and compares this with the new Nonel short panel system.

Jan 1, 1990

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

By Zhou Jiahan Wang Feng

This paper introduces the mechanism and the operating process of dike building by silt squeezing blasting. DBSSB (dike building by silt squeezing blasting) has the following advantages: shorter construction period (the construction period is decided only by the speed of rock materials filling)greater consolidation of the body of the dike, more structural stability, smaller settlement. Therefore by conventional standards the same dike can be designed with a smaller cross section than other construction methods, and at a reduced cost when enough rock materials can be provided in site.

Jan 1, 2006

By T I. Jerman

The Du Pont "Detaline" nonelectric initiation system utilizes a low energy detonating cord. It is compatible with conventional detonating cords and shock tube downlines as well as nonelectric in-the-hole delay caps. "Detaline" millisecond surface and in-hole delays offer a great degree of flexibility in developing effective delay patterns for improved fragmentation and reduced vibration. All components are easily assembled in the field.

Jan 1, 1982

By S Lukovic, Vishwa Bhushan, Calvin J. Konya

Effect of each of these variables has been well characterized for ANFO. This paper presents results of underwater energy measurements for one watergel and one emulsion type of slurry explosive which were initiated by 3 types of initiators (one electric and two cords of different strength) in 2 and 3 inch diameter steel pipes. Results of this 2 x 3 x 2 factorial experiment show the effects of detonating cord on energy released by the watergel and the emulsion explosive. Effect of diameter and its interaction with cord strength have also been characterized for the two explosives.

Jan 1, 1986

By R W. Givens

This paper discusses emulsion performance and characteristics. Also presented are pattern design equations by a weight strength method, a "Q" factor method, and a coupled energy powder factor (CEPF) method. Pattern expansion by replacing ANFO with emulsion is presented along with quality control checks for emulsion products. The predicted performance of the calculated burden and the equivalent powder factor as a function of the emulsion percentage, as determined by the three methods, is compared. Field results indicate that of the three methods the weight strength is the moot conservative, the "Q" is overly optimistic, and the CEPF more accurately predicts the effect of coupling and is more consistent with a variety of emulsion and heavy ANFO products.

Jan 1, 1989

By Kamal Wadhwa

Ever since the introduction of Liquid oxygen explosives in India in 1927, these explosives are being extensively used in the various mining industries such as coal, ironore, limestone, bauxite, magnesite etc. The earlier LOX compositions were based on cellulosic material of Weberlox series of French origin. They contained the basic ingredients of saw dust with an admixture of cork dust, some hydrocarbons and some metallic powders. However, there were some inherent defects in the soaking characteristics of these compositions, in as much as, absorption and retention of liquid oxygen in the cartridges were not properly regulated in the fine pores and in the inter-granular spaces inside the ingredients in a uniform manner.

Jan 1, 1989

By P Cotton, N Cox

The Brisbane City Council has implemented a program of continual improvement at its Mount Coot-tha Quarry in the heart of Brisbane, Australia. The program has been underway for the past 6 years, and has resulted in very significant improvements in terms of both the cost effectiveness of its operation, and in terms of its environmental impact on nearby residents. The work has included a focus, amongst other things, on blasting efficiency, and has challenged conventional thinking in terms of the size of blasts fired, the frequency of firing, the diameter of blastholes, and the use of bulk emulsion or slurry explosives.

Jan 1, 1995

By Dale S. Preece

A Discrete element computer program named DMC (Distinct Motion Code) has been developed for modeling rock blasting. This program employs explicit time integration and uses spherical or cylindrical elements which are represented as circles in 2-D. DMC calculations have been compared with measurements on bench blasts in the field with relatively good comparison. Structural geology and joint sets have a significant impact on any blast and DMC has not, until now, included these effects. This paper discusses a recently added DMC capability for treating joints and bedding planes in bench blast simulations.

Jan 1, 1995

By Dwayne Tannant, Jeffrey Loeb

Blasting techniques and protective measures exist that can mitigate risks associated with flyrock and the nuisance of vibration, and overpressure. However, these are often misused or not used because there are no prescriptive regulatory requirements and typically urban blasting guidelines do not exist. The relationship between the increasingly negative publicity that the urban blasting industry receives and the existing state of regulatory control on blasting in urban environments is presented.

Jan 1, 2012

By Dr. Kyle Perry, Ryan Sibley

Rock blasting is an inherently difficult field to quantify independent & dependent variables and the specifics of how the energy interacts with the material for a number of reasons. Independent variables such as geology are innumerable and stochastic, thus, on a laboratory and full-scale basis these variables are assumed to be homogenous across the desired rock boundary. Dependent variables are difficult to quantify in the laboratory based on the specific aspect of the fracture mechanisms that caused the fracturing. The same variables are difficult to quantify in the field because of the shear amount of material being blasted. The energy interactions with the material are difficult to quantify due to the rate of the reaction and the lack of quantification of independent variables. The second main issue with laboratory scaled rock blasting is the nature of the small form-factor explosives required for use in a scaled setting. These explosives that are utilized, traditionally PETN detonating cord, have a greater ratio of potential energy converted to shock energy rather than gas energy when compared to traditional field explosives, such as emulsion or ANFO. Research over the past decades has indicated that gas pressure has the greatest contribution to rock blasting performance, such as fragmentation and material throw. The factor of varying ratios of energy production has not been discussed in any of the reviewed publications. Publications discuss dimensionless scaling, dynamic similitude, and length-based scaling, however, none of these scaling methods discuss the ratio of energy production. The main focus will be correlation of energy production ratio of shock versus gas to dependent variables. This paper analyzes previous publications within rock blasting and related field as they pertain to scaling procedures and will highlight the similarities and differences in the various publications and detail the observed omitted variables that possibly lead to skewed data.

Jan 21, 2025

By D T. Froedge

The state of Kentucky is making some changes in it's blasting program namely instituting a training program for blasters and instituting a new classification of blaster titled "Class A Kentucky Blaster". These changes will take place within the next year and are felt to be of great interest and benefit to those in the blasting industry.

Jan 1, 1978

By John W. Brown

During the summer of 1994 the mining industry experienced numerous accidents involving blasting related incidents. The Tri-State Chapter of Explosives Engineers planned a meeting to discuss three of these accidents.

Jan 1, 1995

By Ann Barron, Paul Downing

Those employed in the explosives industry must have a keen familiarity of the explosives products they handle, the safety pro c e d u res they must follow, and the increasing number of laws and regulations governing blasting operations in order to perform their duties satisfactorily. For this reason, companies must make certain that their employees have the necessary knowledge and full understanding of their blasting and non-blasting responsibilities. Consequently, training is one of the most important elements in any company’s safety program.

Jan 1, 2004

By V R. Sastry, D P. Singh, N R. Thote

Rock parameters which are uncontrollable impose restrictions on the procurement of desirable fragmentation. Blast design parameters which are controllable prove to be important tool in blasting operations. An attempt was made by the authors to investigate parameters which causes big oversize boulders in overburden blasting. A case study of coal mine is discussed in this paper.

Jan 1, 1995

By James R. Houston, Wendel Clay Chaffin, John Loviza

During the spring and summer of 1993 the largest pipeline in Tennessee was installed as part of the upgrading of Nashville's sewage needs through the year 2035. This new 3.3 million dollar outfall project is able to carry 330 million gallons of treated sewage water daily. Special projects required special equipment as this project was safely and quickly installed.

Jan 1, 1995

By Mark S. Stagg, David E. Siskind

The Bureau of Mines arranged to have a wood-frame test house built in the pat of an advancing surface coal nine so it could investigate the effects of repeated blasting on a residential house. Structural fatigue and damage were assessed over a 2-yr period. The house was subjected to vibrations from 587 production blasts with particle velocities that varied from 0.10 to 6.94 in/s. Later, the entire house was mechanically shaken to produce fatigue cracking. Failure strain characteristics of construction materials were evaluated as a basis for comparing strains induced by blasting and shaker loading to those induced by weather and household activities. Cosmetic or hairline cracks 0.01 to 0.10 mm wide occurred during construction of the house and also during periods when no blasts were detonated. The formation of cosmetic cracks increased from 0.3 to 1.0 cracks per week when ground motions exceeded 1.0 in/s. Human activity and changes in temperature and humidity caused strains in walls that were equivalent to those produced by ground motions up to 1.2 in/s. When the entire structure was mechanically shaken, the first wallboard tape joint crack appeared after 56,000 cycles, the equivalent of 28 yr of shaking by blast-generated ground motions of 0.5 in/s twice a day.

Jan 1, 1985

By Tristan Worsey, Nathan Rouse, Daykin Schnell

The authors were retained by a proposed underground metals mine operation to evaluate the potential blast vibration amplitudes that could be generated at surface structures above the proposed mine. Literature reviews of published blasting documentation gave little information, data, or models on surface blast vibrations produced by underground mines. At the client’s request, the authors contacted a number of underground mining operations to evaluate interest in sharing blast vibration data with the authors so that the authors could develop an underground-to-surface blast vibration regression equation. The authors worked with three underground metals mining operations to collect surface blast vibration data produced by heading blasts and stope blasts. The data included blast vibration amplitude values, seismograph records, blast design geometry, charge weights, and detonator delay and sequence designs. The total amount of information was used to produce a regression equation and summary dataset that could be used by the proposed underground mining operation to evaluate blast vibration amplitudes that will be generated on the surface. This work is published and presented so that operations with proposed underground mines or proposed underground mine extensions can use these equations to predict vibration amplitudes on the surface above the mine workings before any blasting occurs.