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By Carl Hendricks, Malcolm Scoble

There currently exists no viable means of obtaining continuous, quantified feedback on blast efficiency. This paper describes the adaptation of a loading shovel to serve as a diagnostic tool in evaluating the success of ground preparation practices. Work undertaken in a large western Canadian open pit involved microprocessor-based instrumentation for the performance monitoring of an electric mining shovel. The monitored shovel responses proved to be reliable indicators of variations in muckpile d&ability. This approach is considered to provide a very comprehensive survey of post blast conditions since the shovel must physically interact which every cubic yard of blast fragmentation.

Jan 1, 1991

By Douglas Anderson

Even though there is always a feeling of anticipation before a blast is detonated, most blasts are part of a day’s work. Once in a while there is an event that impresses even the most jaded blaster. Few blasts have had the impact of the Kingdome implosion in March of this year. Fortunately for both the Seattle area and the explosives community, the “impact” of the implosion was far less than many local residents had feared. This outcome, of course, was not by chance, but the result of careful planning and design. An urban implosion requires a mix of engineering, logistics, and public relations. Unique challenges on this project tested the resourcefulness of the entire team.

Jan 1, 2001

By A B. Opperman

For many years explosives energy has been utilized in mining and construction as well as many other applications which are vital to our way of life. Many types of explosives have made their contribution as technology has moved forward. One of the best known was dynamite, which for many years was the mainstay of explosives users. Although dynamite had many advantages over its predecessors, it had the principal shortcomings of being somewhat hazardous to handle and was known as a headache producer.

Jan 1, 1975

By Douglas Bartley, Robert McClure

This paper discusses the advances in programmable, testable high accuracy electronic detonator technology. The operation and safety of electronic detonator systems are required to meet rigid safety standards and withstand the demanding environment of in-field applications. These requirements are discussed through comments on existing safety requirements in Europe.

Jan 1, 2000

By Brian W. Stump

"Seismic waves from explosions can be used to characterize physical processes in and around the source. The quantification of absolute levels of ground motion is important for minimizing impact on nearby people and structures. We contrast work in characterizing seismic radiation from contained nuclear explosions with ground motions from multiple explosion quarry blasts. A physical basedunderstanding of the explosion source function allows prediction and extrapolation to new environments where experimental data may not exist."

Jan 1, 1990

By Boris Belenky, M M. Graevsky, R I. Semigin, A E. Frantov

"In the mining industry, most of stripping and rock fragmentation is performed by blasting. The academician N.V. Melnikov has projected that blasting methods would be used to crush 20% of soft rocks and 80435% of medium and hard rocks. Thus, the volume of blasting will continue to increase.This is especially true for electrical blasting, since this method has a number of well known advantages, and in some cases (e.g. for underground blasting in coal mines) it is the only acceptable method."

Jan 1, 1995

By Richard R. Brochu

At the International Society ofExplosives Engineers Annual Conference held in Nashville, Tennessee in February 1995, a Seismograph Standards Committee was established. The purpose of this wmmittee was to develop objective performance specifications for vibration measurement instrumentation and field use practices. It was also understood that due to geology, temperature, and moisture in the soils, it is not possible to design and build an instrument to give ‘results which are absolutely comparable for ground vibration. It was, however, considered essential to standardize instrumentation by which vibration can be measured under closely defined conditions so that results obtained by users of seismographs are always the same ,&thin stated tolerances.

Jan 1, 1998

By Jean-Guy Levaque, Robert Ethier, Ron J. Elliot

This paper presents data gathered during a comprehensive study on the impact of improvements to fragmentation in a major Limestone quarrying operation. The full impacts of gains in fragmentation are tracked through the mucking, crushing, and grinding phases of the operation.

Jan 1, 1999

By Randall S. Marks

Bonneville Dam, completed in 1938, included the smallest and busiest lock on the Columbia and Snake River Navigation System. To expedite barge traffic through this restriction, a new larger lock was designed and contracted by the U.S. Army Corp of Engineers.

Jan 1, 1997

By Ali Kahriman, Alper Celtikc, Serdar Celik, Tuncer Gungor

This paper presents the results of ground vibration measurements carried out in Gülyali Hisarcik Basalt open pit mine located on the north side of the Anatolia near Ordu province in Turkey. Within the scope of this study in order to predict peak particle velocity level for this site, ground vibration components were measured for 5 shots during bench blasting. In blasting operations; ANFO (blasting agent), gelatin dynamite (priming) and delay electric detonators (firing) were used as explosives. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured for all blast events using 5 different vibration monitors (4 White Mini-Seis and 1 Instantel Minimate Plus Models). The absolute distances between shot points and monitor stations were determined using GPS. The equation of square root scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity.

Jan 1, 2013

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC-BLAST (Distinct Motion code) has been under development since. 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in two dimensions (2-D). DMC-BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1998

By Brian Gar Wingfield

"The introduction of the QuarryMan laser profile system in 1987, along with the development of the corresponding 3-D software, gave a qualified operator pertinent information about dimensions of quarry highwalls, pattern and hole loading design, stockpile profiles, etc . . . Attributes helpful for this endeavor included surveying, computer, and blasting knowledge. Since not all operators had theseskills, a simpler model, the QuarryAce, was designed to look a t highwall dimensions in 2-D view . Al though less sophisticated than the QuarryMan instrument and its software, it is simpler to instruct in its use and has the ability to determine burdens at different depth levels . An in-house user f r i e n d l y computer program was designed to utilize QuarryAce depth vs. burden data . This program was created to enable laser and computer novices to generate information useful to the everyday blaster."

Jan 1, 1992

By William Stewart

Recitations were taking place in the red schoolhouse at Orneville, Maine. It was winter and the snow lay deep on the ground, but some of the scholars were in bare feet, and only half as many hats hung on the pegs as there were potential wearers in the seats. That was forty years ago; and the pioneers of northern New England were more noted for their industry than for their possession of the fruits of it.

Jan 1, 2007

By Stephen H. Chung, Kevin Atherton

The main purpose behind this preliminary study was the reduction of costs while maintaining productivity. Finding a way to achieve this balance without compromising controls on safety and quality of blasting results is of continual interest to the mining industry and of particular interest when ore of lower grade is being mined.

Jan 1, 1998

By Stephen Chung, Graham Mustoe, Joe Haid

In an open cast coal mining operation, a 305 m (1000 ft) long by 49 m (160 ft) thick overburden cast blast can produce more than a million cubic yards of broken muck that needs to be removed before the coal recovery process can start. In the Powder River Basin of Wyoming, it is common to see 30 to 40 percent of the overburden cast to a spoil that does not require rehandling with heavy equipment. Therefore, the higher the percent cast, the better the cast blast is rated. However, depending on the shape of the muck profile, there is often 20 to 30 percent of the muck standing in front of the high-wall. This portion of muck would require a number of dozers to push down to the dragline pad level. From the mine operator point of view, it is believed that for a given muck profile, there should be an efficient dozer pushing method such that a dragline pad can be developed in the shortest time. As a tool for analyzing this dynamic problem, a 2-D discrete element model, i-PushTM, has been developed to simulate a dozer pushing operation. This mechanistic model takes into account the dozer blade geometry, the dozer operating procedure (e.g. cut-depth, blade fill distance, forward and reverse speeds at specific slope angles), material density and cohesion. To demonstrate how i-PushTM can be used to help determine the most productive push routine, this paper presents three dozer push methods to compare the effectiveness of pushing at 3:1, 4:1 and 5:1 push angles.

Jan 1, 2006

The common approach of designing blasts on a trial and error basis is quickly coming to an end. When utilizing the full scale blast environment, trial and error can quickly become cost prohibitive and leaves much to be desired in terms of true blast diagnostics. In these situations testing is usually only continued until a perceived improvement is achieved and when the gross undesirables in blast results are removed. This does not preclude, however, that further improvements of up to 100% or more can not be obtained.

Jan 1, 1994

By J W. Simmons, T H. Antoun

"Rock fragmentation is an important component of explosive mining and excavation techniques andis the culmination of a damage accumulation process dominated by crack propagation. During the past 20 years, improved computer modeling of this process has resulted in new and promising computational tools for improving explosive mining and excavation procedures. This paper discusses one of these new computational tools, a computer model called BFRACT."

Jan 1, 1995

By C. Pelley, S. Kelebek, P. D. Katsabanish, M. Pollanen

A series of small scale tests have been conducted to evaluate the effect of blasting on the grinding resistance of rocks. The samples consisted of homogeneous blocks of granodiorite and limestone while blasting was performed using single and multi hole configurations. Grinding resistance was evaluated using relative ball mill tests, rod mill tests and the SAG Performance Index test (SPI) developed by Minnovex. It was shown that the grinding resistance was affected by blasting. However the effect depended on the final product size. In the case of the coarse grained granodiorite, a negligible effect was observed for grinding below the natural grain size of the rock, while the fine grained limestone exhibited more significant changes, in the range of 13-16%. Grinding of granodiorite in the coarse size range indicated a general reduction of its work indices, as evidenced by the results obtained from the ball mill, the rod mill and the SPI tests.

Jan 1, 2004

By Thierry Bernard, Jean Marc Laboz

This paper explains why and how integration of EIS (Electronic Initiation System) with dedicated software tools can increase benefits to blasters and at the same time simplify the design of blast sequence

Jan 1, 2000

By Dale S. Preece

The computer program. DMC Qistinct Motion &de), which w&s developed for simulating the rock motion associated with blasting, has been used to study the intluence of row delay timing On rock mOtiOn. The munerical simulations correspond with field observations in that vmy short delays (< 5Oms) and vety long delays(> 3oOms) produce a lower percent-cast thao a medium delay (100 to ZOO ms). The DMC predicted relatio&lp between row delay timing and percent-cast is more complex than expected with a dip in the auve where the optimum timing might be expected. More study is required to gain a full undasranding of this phenomenoo.

Jan 1, 1994