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By Yves Lizotte, Malcom Scoble, Pierre Michaud

The concept of optimum fragmentation in surface mining operations, i.e. the degree of fragmentation to which corresponds the lowest overall associated costs of drilling, blasting, loading, haulage and crushing, was developed more than thirty years ago. Recent field investigations using novel technologies, which have been completed by ICI Explosives Canada and by others, indicate that this ultimate goal of optimum fragmentation is closer to becoming reality.

Jan 1, 1997

By R M. Bhatawdekar, A I. Theresraj, H S. Venkatesh

Wadi Limestone Quarry is one of the largest captive mines of Associated Cement Companies Ltd, India. The mine management wanted to extend the excavation as close to the plant as possible for maximum exploitation of the deposit. The National Institute of Rock Mechanics and the management of Wadi Limestone Quarry carried out comprehensive investigations to evolve a methodology to control vibration and flyrock within safe limits.

Jan 1, 1999

By Jack Elorenta

A recent forum of mine operators revealed a continuing strong interest in alternative methods of freeing rock. A Rand Corporation report lists a continuous mechanical machine that would replace drilling and blasting as a priority for mine operators. Meanwhile, mounting evidence documents a dramatic cost benefit in processing where increased blast energy is available. The reasons for this dichotomy may be due to a number of factors.

Jan 1, 2002

By Dale S. Preece, Steven Knudsen

A discrete element computer program, DMC (Distinct Motion Code) was developed to simulate blast-induced rock motion. To simplify the complex task of entering material and explosive design parameters as well as bench configuration, a full-featured graphical interface has been developed. DMC is currently executed on both Sun SPARCstation 2 and Sun SPARCstation 10 platforms and routinely used to model bench and crater blasting problems.

Jan 1, 1994

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 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 James Rowland, Richard Mainiero

When most people think of explosives transport they think of a hazardous operation. We all know that we aren’t allowed to transport explosives through tunnels and are discouraged from traveling through heavily populated areas. Popular opinion suggests that explosives transport is a very risky operation. The authors decided to look into this a little more thoroughly and found just the opposite to be true.

Jan 1, 2008

By Dick Green

During the recent troubles in Northern Ireland due to terrorist activities, there have been many buildings demolished or damaged by improvised explosives. This article explains about the Demolition of Churchill House in Belfast, the first controlled use explosives to demolish a high rise office building since the recent troubles started, and a further indication that normality is returning to the lovely city in Ireland.

Jan 1, 2006

By Dale Preece, Stephen Chung, Qian Liu

Stoping is one of the widely adapted methods in underground mining. In this method, fanned or parallel holes are often drilled from a top sill down to a sub- level in the ore zone and blasted ring by ring into a stope for excavation. At Brunswick Mine of Canada, this technique has been used daily in conducting production blasts. However, when mining into the West Ore Zone, it has been identified strategically that a mass stope blast, involving the blasting of rock from the 3-sub level down to the 1-sub level, should be considered to ensure the safe operation and regaining of access to the trapped main ore zone. The challenge of this mass blast lies in the control of ground vibration and precise timing for blasting 800 holes drilled in six blocks from three different levels within 6.5 seconds, to allow sufficient void to be created in each level for the muck moving in order from the upper to the lower levels without bridging. This paper describes stope blast simulations using a discrete element computer code for modeling blast-induced rock displacement in conjunction with a precision electronic programmable delay timing system for various stope geometries including a drop raise blast at the start of the mass blast. The modeling concept is also described in the paper.

Jan 1, 2003

By Sheila Luchansky, F M. Babcock, Daniel M. Sanders

A cooperative effort between a blasting vibration consultant, a blasting contractor, and personnel from the City of Las Vegas has dramatically reduced complaints from residential areas near developmental blasting projects. The principal methods used involved the preparation of an informative video recording which presents various aspects of the blasting operations, the design of a distinctive flyer which is attached to residential doors, and pre-blast meetings for information dissemination.

Jan 1, 1993

By Calvin J. Konya

Precision Blasting has designed easy to use, yet, highly powerful databases for storage and retrieval of blasting data. Three different Databases are available for blasting data management. The Vibration Data Management is a complete vibration record keeping system. The Blasting Data Management will record the information from the blasting report as well as the vibration data. The Explosives Inventory Control makes the control of explosives and initiators quick and easy.

Jan 1, 1991

By Norman S. Smith, Troy D. Harris, Richard L. Ash

In open-cut bench blasting drilling boreholes below grade level is normally considered essential to insure toes do not remain. The extra drilling and use of explosive below floor level are not only expensive but on occasion cause serious problems including severe floor damage and excessive ground vibrations. It has been reported that under certain circumstances explosive in the subdrilling has been successfully substituted by broken rock with its associated benefits.

Jan 1, 1978

By Evan Boone, Peter Bellairs

A technical services visit was conducted to determine the initial parameters to successfully presplit several benches for an input crusher installation at the Wolffdene quarry. The paper details the preliminary design utilising both detonating cord only and specialised presplit product charges and compares these to the final designs utilised based on site experience. The role of accurate drilling, explosive loading and geology in obtaining successful cost effective presplits is highlighted.

Jan 1, 1998

By J P. Tidman

The problem of blasting fragmentation has received a good deal of attention in recent years. Progress by the scientific method requires a good set of experimental data as a benchmark to test models. Recent models have become so complex that it is not possible to use the results of field data because the complete set of parameters needed to describe the rock and/or explosive are not available.

Jan 1, 1991

By Francis O. Otuonye

An application of a time series and systems analysis modeling technique to blast vibration data is discussed. The vibration data was taken from a rock support structure and the surrounding rock mass at distances close (less than 15 feet) to a blast. The analysis technique provides quantitative information on the frequencies of ground motion as well as the frequencies and damping ratios of a near-field support structure.

Jan 1, 1994

By Roger L. Keller

This paper examines the aspects of differing types of blasting cuts in underground headings with consideration to the reduction of number of holes and costs. At least one comparison study is related where costs per advance meter were significantly improved. The technical aspect of the paper covers a study of the effects of various blasthole delay intervals on resulting crater volume, ground vibration, and fragmentation for six hole V-cuts.

Jan 1, 1989

By Abdel Rahman, M. Khaled, Abo Makarem

There are four large limestone quarries, located nearby Cairo metropolitan. Drilling and blasting operations are used to extract limestone for the cement industries. In these quarries, the blast vibration should be kept below a certain limit. One of these quarries is Tourah Portland Cement Company (TPCC) limestone quarry which, lies near important and historical large caves, within Tourah Mountain. Therefore, control of blast vibration level becomes very critical.

Jan 1, 2007

The use of angled shot holes can be extremely effective in blasting faces that either have a great deal of toe burden or where it is difficult to give a drill access to a face due to backbreak and face erosion. However many quarry operators are wary of using angled holes because of the perceived possibility of increased flyrock and uncertainty of the driller's abilities to drill at the designed angle.

Jan 1, 1994

By Sung Su, Jui-Lin Chang

A new technique of dimensional stones blasting for achieving directional rock cutting by conical shaped charges is proposed in this study. This technique has many advantages like precisely controlling numbers and propagation directions of cracks under blasting, having a complete rock excavation face, and maintaining surrounding rock and slope’s stability. So it can be applied to quarrying, underground excavation, tunneling, rock slope blasting, bench blasting and dimensional stone blasting.

Jan 1, 2006

By John T. Watson, Jim Bailey

Increasing public awareness is probably the single most important challenge faced by any blasting contractor today. This increased awareness usually results in an outcry for tighter regulations and restrictions on those in the blasting industry. Those affected do not often understand the dynamics of blasting and are simply fearful of the unknown. This reaction very often results in more regulations and restrictions which frequently fail to address the real problems.

Jan 1, 1990