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By Bryan J. Lane, Paul N. Worsey

The recommended maximum explosive weight for boulder blasting using internal charges is 0.1 O-kg/m” (3.5 oz./yd) (Olofsson, 1988). Normally this charge results in excessive scattering and flyrock, creating increased liability for the operator, especially in congested areas. An alternative technique using smaller explosive charges is being developed at the University of Missouri - Rolla. It is designed to reduce boulder scatter, flyrock and fumes and allows shooting in close proximity, using common blasting products.

Jan 1, 1999

By Doug Anderson

Two quantities, Peak Particle Velocity (PPV) and Scaled Distance (SD), have controlled aspects of many blasting projects and operations for a long time. Vibration criteria typically use both PPV and SD because they are simple to measure, and simple to calculate. Their use in regulations worldwide is fairly ubiquitous, in efforts to limit damage to structures in the neighborhood of a blasting operation. PPV and SD are also used to determine likely blast damage effects in mining operations.

Jan 1, 2018

By Jennifer P. Harrell, D. Joseph Hagerty

In many areas of the eastern United States, especially in the Midwest, past mining activities have left large and extensive underground openings. Now, renewed mining is occurring in such areas in surface pits. Also, construction blasting often occurs in rock over such old openings. Within the last fifteen years, some attention has been given to the interaction between surface blasting and underground cavities; concern has been expressed about the possible changes in vibrations transmitted through areas underlain by old mine workings (Siskind, Stachura and Nutting 1987). Previous studies also had indicated that underground openings could influence transmission of surface mine blast vibrations (see, for example, Woodward-Clyde Consultants 1977). The principal concern is that underground openings under surface blasting may intensify low-frequency vibrations. If such intensification occurs, use of available equations to predict peak particle velocities and to design blasting patterns and select blasting parameters could lead to possibly damaging ground shaking.

Jan 1, 2002

By Jorge Flores, Benjamin Cebrian

Blast Optimization at a high altitude mine operation involves not only the selection of the right drilling designs and explosives but also the circumstances of operators working at low oxygen levels and low temperatures.

Jan 1, 2015

By Advanced Initiation Systems Inc

10 years in R&D Last 5 years available commercially Worldwide Met strict approvals for manufacturing and use

Jan 1, 2004

According to the Directive 93/15/EEC, given on 5th of April 1993, all the commercial explosives placed on the market and transfered in European Union and EFTA countries have to be certified and contain the CE-marking. Before the products can be awarded by the CE-marking they have to fulfil the Essential Safety Requirements (ESR) of Appendix 1 of the Directive. From the beginning of last year the commercial explosives could not have been be sold in Europian Union countries without the CE-marking. The legitimacy of the Directive 93/15/EEC encompasses High Explosives, Detonating Cords, Safety Fuses, Gun Propellants and Detonators. At the moment in Europe, there are seven Notified Bodies (NB) working in the field of commercial explosives. They are in Spain (LOM), Germany (BAM), France (INERES), England (HSL), Netherlands (TNO-PML), Sweden (SP) and in Finland (PvTT). The Swedish SP has qualifications only for the detonators and the Finnish PvTT for High explosives, Detonating cords, Safety Fuses and Gun Propellants, but not for the detonators. The role of the NB is to work as a third independent body between the client and the manufacturer testing, studying and certifying explosives by the commission of the manufacturer. The Notified Bodies are operating independently competing the clients, the explosives manufactures.

Jan 1, 2004

By J. -P. Tshibangu, E. Lefebvre

ABSTRACT : The Tournai’s region in Belgium is characterized by outcrops of limestone that were mined out long ago by different companies for cement and crushed materials. The region is densely populated and the vibrations generated by blasts in the quarries are of big concern. The occurrence of electronic detonators and development of computer sciences brought a new expectation in controlling the vibration level and, hence, carry out bigger blast operations. In this paper we present the results of two experimental blast programs that have been carried out by the Nobel explosive Belgium Company on the Gaurain-Ramecroix quarry to understand the effect of the delay on the vibrations generated in the neighborhood. The first program has been implemented during the early use of electronic caps in Belgium (1996) by performing some unit shots. An attempt to model the effect of the production blasts by the hybrid method (Hinzen 1988) gave promising but poor results compared to infield measurements. A new program (more than ten blasts) has been implemented in 2006 in which the delay and blast firing sequence (i.e. the order in firing adjacent holes in a row) have been changed; a new attempt is made to build unit signals by deconvolution and then try to model production ones. A comparison of the two approaches is made.

Jan 1, 2008

By C W. "Mickey" Bradley

Thunder strikes terror in the hearts of man and has since the advent of time. We all fear the unknown; even the Greeks created a god, THOR, to be responsible for the thunder and rain. Thunder, by itself, can't hurt anyone; it is simply hot air moving very fast. Thunder, however, is caused by lightning and lightning is what we need to fear and rightfully so. Annually, lightning kills hundreds of Americans, injures another 2,000, damages or destroys approximately 30,000 structures, 1 starts thousands of forest fires and strikes mine properties over 100,000 times.

Jan 1, 1992

By NA NA

Copyright © 2020 International Society of Explosives Engineers

Feb 1, 2020

By Larry Schneider

In the construction field and to a lesser degree in mining, flagman are often necessary to move traffic and or pedestrians through work zones. Everyone readily recognizes that they are essential for the safety of the general public and the employees on the job. What is not often considered is the safety of the flagmen themselves. Actually, let’s call these employees “flaggers” recognizing the fact that there are as many women as men doing this job. The first problem we need to overcome is the misperception that flagging is a low skill function that can be done by any untrained employee. The reality is that the flagger works in a very hazardous position with serious responsibility for the safety of his fellow employees and the public at large. And to do this job properly re q u i re s that the flagger receive sufficient training before being sent out to the highway. It is also necessary to convince the flagger of the value and importance of their job in order to motivate them to do a professional job.testing, documentation of both, and accurate re c o rdkeeping are key aspects of HM126F. Of course, training and documentation requirements will vary depending on the type of operation involved, and there may be some differences in the application of requirements depending on your jursdiction. Nonetheless, failure to train and properly document such training can result in heavy fines and/or penalties.

Jan 1, 2004

By Robert Hopler

A detonator is a copper tube about a quarter of an inch in diameter and an inch and a half long, closed at one end and containing in the closed end a small charge of fulminate of mercury, which has been found to be the best explosive for detonating dynamite. The fulminate charge is a very powerful explosive very sensitive to friction, lows or heat and very poisonous. When exploded it has an intense local action, shattering things in its immediate vicinity, but not extending very far away from the explosion. This kind of detonator is intended to be exploded by a spark from burning fuse.

Jan 1, 2014

By M. Khaled, K. Abdel Rahman, M. Khattab

Helwan limestone quarry is located at a distance of 35 km (21.7 miles) to the south of Cairo downtown. Drilling and blasting operations are used to extract the limestone for the Helwan Cement Company (HCC). In 1980’s a new urban community was constructed adjacent to the quarry. This situation led to shifting of the old quarry 5.0 km (3.1 miles) to its current location, to avoid causing blasting problems to the new community. Unfortunately, the new quarry is opened in a highly faulted area, with weak zones of brittle materials. The drilling and blasting crew is facing many difficulties due to the geological complexity along these zones. Moreover, the extension of this community towards the new quarry makes the control of ground vibrations is very important.

Jan 1, 2008

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 Jacques Monette, P K. O'Connell, Keith Boyle

The mine contracting industry in Canada is no different from any other industry in its quest for productivity improvements. Dynatec Mining Ltd. has focused on drilling and blasting of rounds as an area for improvement. This paper describes the development of blasting long rounds in shaft sinking as well as a description of the lateral excavation system as applied at Aur Resources Inc., Louvicourt Project.

Jan 1, 1994

By J S. Brower

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

Jan 1, 1978

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 J Paul Tidman, Stephen H. Chung

One of the requirements in open pit gold mines is to minimise the mixing of ore and waste. Dilution can be reduced by choke blasting and control of the initiating sequencing. The authors have used the DMC computer model (developed at SANDIA) to examine the effects of timing and charge distribution on ore dilution. The model has been calibrated by measurements of vertical uplift derived from high speed videos made at the Dome Super Pit in Timmins.

Jan 1, 1997

By Tom Short, Bill Beam

Some of the weapons testing shafts at Mercury, Nevada require depths of 1000ft and diameters of 10 feet. The top 40 feet to 65 feet is drilled, blasted and excavated by Large caisson type augers in order to provide vertical working room for the placement of large, oil field type, drilling rigs and the required drill collar.

Jan 1, 1991

By R Frank' Mammele Chiappetta, Conny Postupack

A major problem that has continued to plague the surface coal industry is blast induced damage to the coal seam. Atlas Powder Company has addressed this situation through seven years of field research in full-scale production environments. Many operations across the United States have been evaluated.

Jan 1, 1988

By Richard Arsenault

The production of oil & gas from wells requires method of flow from the producing formation into the well bore. Once the well is drilled it will have casing pipe installed to protect the integrity of the well formations and means of delivery to the surface. Once casing pipe is installed it will be cemented in by pumping cement through the annulus of the casing pipe down to the bottom of the well and allowed to flow outside the casing pipe up into the formation.

Jan 1, 2007