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By Stafan Rose, Art Madsen

Four years ago, Peabody’s North Antelope Rochelle Mine (NARM) site started experimenting withANFO and Liners in its Cast Blasting operations. The motivation to use ANFO was based on the following:1. ANFO generates more gas thereby resulting in greater heave/movement. 2. ANFO is a more consistent product because there are less components/ingredients. 3. ANFO when protected from water contamination does not produce NOx smoke.

Jan 1, 2007

By N L. Thomas

Hole size affects many factors which directly influence fragmentation in the muckpile and hence, the cost effectiveness of the entire operation. These factors include production capability, explosives and accessories efficiency and usage and drilling accuracy. In addition, hole size should be chosen to suit the geological conditions. The paper concludes that the optimum hole size is generally the largest that can be used commensurate with production and environmental considerations.

Jan 1, 1986

By Steven P. Case

To meet salt production needs over the remaining life of the Cayuga Mine at Lansing, New York, the Salt Division of Cargill, Inc. decided to build a new underground screening plant. The new plant required a chamber 50 feet wide by 250 feet long and nearly 70 feet high. On advise of their mining contractor, Dynatec Mining Company, the company chose an ingenious excavation method similar to sublevel stoping. This method eliminated the need for an access ramp, reduced equipment needs and excavation time substantially.

Jan 1, 1996

By Ken Tunnel

In the spring of 2005, the Lake Superior Chapter of the ISEE invited me to speak about raw materials used for blasting, anhydrous ammonia and the effect of this important feedstock on the cost of ammonium nitrate.The invitation was extended because our company is involved in trading ammonia and the production of ammonium nitrate. In a response to a request to update that presentation, it struck me how events such as hurricanes Katrina and Rita can change the landscape of our businesses.

Jan 1, 2007

By Roger L. McCarthy, Ali Reza

The use of an ammonium nitrate-fuel oil (ANFO) explosive in the Oklahoma City Federal Building bombing has led to a renewed interest in using additives during the manufacturing process of ammonium nitrate to render it non-detonable. Suggested additives include calcium carbonate, which is already used in some European countries, and mono-ammonium phosphate (MAP) or di-ammonium phosphate (DAP), which are the primary desensitizing agents claimed in US patent 3,366,468, Method for desensitizing fertilizer grade ammonium nitrate and the product obtained, issued Jan. 30, 1968 (Porter, 1965).

Jan 1, 1999

By R Holmberg, C Sjoberg, B Larsson

This paper describes the excavation of an underground naphta storage facility at Stenungsund in Sweden. The main purpose with this paper is to give an overall view of how the excavation was carried out and in what type of bedrock the storage was built. Emphasis has been done to highlight the importance of using cautious blasting to avoid blast damage in the remaining rock. Attempts has also been done in order to evaluate what the degree of Swedish cautious blasting has meant for the rock support costs during the construction period.

Jan 1, 1984

By Francisco Sena Leite, Vinicius Miranda

Mine blasting is directly associated with ground vibration. If these affect critical structures (buildings pit walls, etc.) they must be mitigated to reduce the environment and social impacts. Vibration monitoring and control is one of the most important procedures in blasting because it will impact short and long term incidents associated with this blast effect. Technology moves ever forward, and today we have personal devices that are equipped with an array of sensors, for that reason the authors decided to investigate the possibility of using a personal device to do vibration control. This case study compares the same blast measured with a traditional seismograph and a smartphone. To validate this new methodology, attenuation laws were built with data from a traditional seismograph and a smartphone application. Predictions were also made prior to a set of blasts. Residual analysis was used for data validation from the two different sources. From the performed analysis, to prove the validity of this new methodology, the normality tests for statistics residues analysis proves that it is possible to infer that the model has a null residual mean and a small residual error. The achieved results show the accuracy of these devices, the authors pretend to show the potential of this equipment and open a completely new door for vibration analysis.

Jan 1, 2018

By Huang Fenglei, Jin Qiankun

A new linear charge method has been applied in coyote blasting for highway excavation in which presplitting boreholes are set along the designed rock slope with some empty chambers at the end of linear charges whose axes are perpendicular to the axis of the highway. Three-dimensional nonlinear finite element analysis for this method has been conducted using LS-DYNA3D. The results indicate that the blasting damage to the rock slope is reduced greatly using the new linear charge method in coyote blasting.

Jan 1, 1998

By Robert G. Lundquist

This paper is a brief summary of work done on mining applications of high energy projectiles. Full scale field testing already completed has used cannons to drive a tunnel, drill large diameter holes, do secondary breakage in an open pit mine, and scale loose rock from inaccessible pit walls. Other applications are suggested in driving development openings, particularly raises. The method will be economically feasible only if cheap liquid propellants are developed.

Jan 1, 1977

By Karl Ingmarsson

A model for drilling productivity and total drilling cost is presented. It specifically addresses down-thehole drilling, but also covers other drilling methods. The important factors are: 1, productivity in tons drilled; and 2, total cost per drill ton. For non-blasthole applications these factors are measured in drill feet and cost per foot. The model focuses on the entire system and allows the operator to optimize the system based on individual drilling conditions.

Jan 1, 1998

By D. Scott Scovira, Rick Webber

The Iron Ore Company of Canada [IOC] is a global leader in Arctic mining applications, and the blasting crew have something to be very proud of. On Wednesday 21 Dec 2005 at 3:28 PM the largest single bench blast in the company history was detonated. The successful firing of this 5.0 million tonne [5.5 million ton] blast surpassed the previous company record of 3.8 million tonnes [4.18 million ton].

Jan 1, 2008

By Leslie Taylor, Kevin Genson

This paper reports on an experimental study of the effect that bottom shaping might have on the impulse delivered to a light armored vehicle due to a buried mine detonating beneath the center of it. The study was restricted to explosives buried in saturated sand and three parameters were varied within the study: bottom angle (0 degrees to 21 degrees), depth of burial of the explosive (1.02 mm to 12.7 mm), and stand off distance (0 mm to 38.1 mm). Six hundred and thirty six milligrams of explosive was used as the explosive load. It has been shown in previously published work [1,2] that Hopkinson scaling works well for the determination of impulse loading on a semi-rigid target plates. Therefore in terms of a full scale test using 4.54 Kilograms of explosive the parameters investigated would cover a DOB of from 19.56 mm to 243.84 mm and a Stand off distance from 0 to 734.06 millimeters. These values nicely cover those of interest to the Marines with regard to the AAV (amphibious assault vehicle). Four angles were investigated at all DOB’s and Stand off distances – 0 degrees, 7 degrees, 13 degrees, and 20 degrees. The results show that reduction in impulse delivered to the target is achieved with an angled bottom on the target plate with a major reduction occurring before the 13 degree angle is reached. Hence vehicles with quite modest bottom angles could help greatly in load reduction with very little loss in utility.

Jan 1, 2008

By Thomas Palangio, Lyall Workman, Jack Eloranta, Tom C. Palangio

The fragmentation distribution of the blasted ore is an important descriptor of blasting results. Traditionally it has been hard to measure quantitatively. Developments in image analysis over several years makes it more feasible to measure fragmentation before crushing on a continuous basis. Post crushing, mill feed distributions can also be measured.

Jan 1, 2007

By Peter G. Bellairs

The traditional concept of Optimum Drill and Blast is that it is achieved when ore is produced at the lowest unit cost and due to the complexities of most mining operations represents a band which extends either side of an overall cost minima. The above definition implies that Optimum Drill and Blast is static and once blasting is within the band around the cost minima then the process is optimised. However mining operations are not static with many events both long and short term impinging on the cost structure and productivity.

Jan 1, 1995

By Jerry W. Schweiker

An extensive computer program has been developed which will store and analyze pertinent blast related parameters such as date, time, shot coordinates, charge, delay times, etc. In conjunction with these blast parameters, measured ground vibration information can be stored. In addition to actual seismograph data, predicted ground vibration in terms of velocity (inches/sec) can be generated for selected receiver locations. The magnitude of the blast generated ground vibration is based on scale distance relationships. The program can be used for planning blasts, to satisfy local environmental regulations and for insurance and/or legal purposes.

Jan 1, 1984

By Ingvar Hansson, Bjorn A. Jonsson, Bernt Larsson

In the Kiruna Research Mine, Sweden, four large open stopes have been mined, leaving intermediate piIlars and crown pillars. At the final stage of mining mass blasting of the crown pillars above two of the stopes was carried out. The crown pillars contained some 290,000 tons of iron ore. In the mass blast a new initiation technique was used, utilizing the new non-electric system NONEL ? UNIDET. The blasting technique including vibration control is described. The mass blast resulted in high recovery, good fragmentation and low vibration levels.

Jan 1, 1986

By Donald J. Moore

It has become more important today than ever before to reduce costs and improve equipment utilization. One area where such improvement can he achieved is in the use of explosives. Effective blast design for efficient use of explosives as well as optimum fragmentation can achieve this. Towards this end we must have available to us a practical design method in which experience and observation can be translated to engineering concepts. We must he able to communicate the design data to field blasting personnel as well as management in an understandable way.

Jan 1, 1975

By Lewis L. Oriard

Some two million cubic yards of sandstone and orthoquartzite were blasted and excavated at Upper Stillwater Dam, located high in the Uinta Mountains in northern Utah. The material was processed to produce concrete aggregate for the construction of the largest roller compacted concrete (RCC) dam ever constructed, and one of just a few in existence. The dam cross-section is shown in Figure 1. The aggregate was sound rock produced from required dam foundation excavation and from a quarry located about 1/2 mile from the dam site. Representative compressive strengths of the sandstones and quartzites were in the range of 20,000 to 30,000 psi.

Jan 1, 1993

By Kevin Dunfield

The Deltadet System is composed of: The Deltadet II electronic Detonator. A Field Terminal to create, modify or simply execute an existing blasting sequence. The radio remote controlled option is composed of a Base Station to program, calibrate and initiate the EDDs plus a Blasting Box to send commands to the Base Station. Blasting lines to connect the EDDs to the Base Station (100m) and Visual Blast software to create or modify a blasting sequence.

Jan 1, 2004

By Dale L. Ramsey

The Pinkerton Tunnel Open Cut Project is part of the National Gateway Clearance Initiative improvement project to achieve a minimum of 6.4 meters (21 feet) of vertical clearance along CSX Transportation rail corridor so that double-stacked intermodal railcars can be transported between Mid-Atlantic States and their ports to Midwest Markets in the U.S.

Jan 1, 2014