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By J S. Kuszmaul

"A computational model of rock blasting is being developed to examine the blasting problems associated with in situ oil shale processing. This model, however, will also be useful as a design tool for the traditional problems in rock blasting. The model includes fundamental treatment of both shock-wave propagation and the accumulation of brittle fracture in the rock. As a result, the model accurately predicts the degree and extent of fracturing as functions of design parameters. The model has proven useful for making parametric studies and for evaluation of alternate blast designs. This paper demonstrates the use of the numerical model to simulate the fracturing induced by the detonation of a vertical explosive column near a bench. The fracturing induced by three differentexplosives indicate that (in the chosen geometry) the most efficient breakage is done by a column of ammonium nitrate and fuel oil mixture (ANFO) used with a toe charge of aluminized ANFO. There was too much unfractured rock left when ANFO was used alone; aluminized ANFO used for the entire explosive column caused excessive fracturing. A final case involves ANFO used alone to fracture a different rock type. This case points out that in a different rock type, the ANFO will not leave excessive unfractured rock."

Jan 1, 1987

By Uli Leiste

Two papers are presented which examine Air Deck Blasting, one from a computational aspect and the other from a shock aspect.

Jan 1, 2016

By Jair Alarcón, Lucas Steffen, Leopoldo Muñoz

Flyrock is one of the most significant hazards associated with blasting in open pit mining, especially for blasting operations near communities. Flyrock can lead to severe injuries, fatalities, and property damage, compromising the license to operate. For this reason, defining exclusion zones is critical to ensure the safety of people and equipment. A very large radius will reduce the risk of flyrock; however, excessive exclusion zones can significantly impact the productivity of the operation and, in some cases, compromise the extraction of ore in critical sectors. Many mine sites use distances derived from pre-established standards, experiences from other mines, or still use simple methods for analysis, like recording blasts with a terrestrial camera and performing deterministic calculations to determine exclusion areas, applying an arbitrarily safety factor for people and equipment. In this paper we present a new approach that allows the calculation of the exclusion zone by measuring critical flyrock parameters with a high degree of accuracy through a new video analytics technology, this data then is used as input to calibrate probabilistic flyrock models to have more robust calculations, allowing optimized and safe exclusion zones. The proposed methodology leverages high-accuracy data and continuous monitoring to dynamically adjust D&B designs and exclusion zones, ensuring maximum safety without unnecessarily restricting operational efficiency. A case study is presented where the application of these new digital technologies allows precise prediction and control of flyrock trajectories, enhancing the accuracy of exclusion zone boundaries. In this case we successfully reduced the exclusion zone radius to 100m, allowing the ore extraction in a critical region close to the community safely. The study shows notable improvements in safety and productivity, including zero flyrock incidents and enhanced protection for nearby communities. The adaptive nature of these digital tools offers scalable solutions for various blasting environments. The paper concludes by recommending the integration of these tools into standard blasting protocols, highlighting the potential for widespread adoption in the industry to mitigate flyrock risks effectively.

Jan 21, 2025

By Jim Breedlove, Stephen P. Case

When a major ground subsidence occurred in the AKZO Salt mine at Retsof New York, the company was forced to pick up their production from a lower mine level. Before full production on the lower level was possible, an escapeway and ventilation shaft would have to be constructed. Construction of a shaft under emergency conditions required some special techniques. Dynatec Mine Construction, Inc. of Lakewood Colorado was awarded a contract for the project.

Jan 1, 1995

By Alan R. Cameron, Alastair C. Torrance

An explosives underwater test facility has been established and commissioned in the Hunter Valley, New South Wales, Australia which allows the measurement of the actual shock and gas energies of the explosive

Jan 1, 1990

By Luis Huaroc, Augusto Sotomayor, Erick Rodriguez, Paulo Fernández, José Ricaldi, Luis Alejandro

The application of the Kuz-Ram model for the prediction of fragmentation is used worldwide, in Coimolache Mine it was used to determine blast domains and optimize the process by obtaining drilling patterns that meet a required X80 and reducing the uncertainty of drilling.

Feb 1, 2020

By Mark S. Stagg, Steven V. Crum

The Bureau of Mines is conducting research to develop methods to control fragmentation and improve productivity in surface mine blasting. As part of this research, PRONT02D, a two-dimensional finite element computer program developed at Sandia National Laboratories, was employed to model the fragmentation produced from RS-50, a single hole, reduced scale bench blast in a massive dolomite. The fragment size distribution obtained from the computer simulation was calculated using a submodel that utilizes the crack density and nominal flaw size values computed by PRONT02D.

Jan 1, 1989

By Roberto Folchi, Hans Wallin, Mara Battocchio

An understanding of explosives science and technology, and the competence to harness it is central to maintaining Explosives capability, national security, and in sustaining a competitive industry. A consequence of eroding this competence is the increased likelihood of explosives accidents. These are often catastrophic as demonstrated by accidents in Nigeria, Russia, Toulouse and Enschede. In addition to the serious loss of life there was the very significant damage to houses, domestic and industrial infrastructure and to the environment at a cost of many millions of Euros.

Jan 1, 2013

By Carlos Pañura, Michael Geldres, Alejandro Rojas

The vibration waves are produced by the detonation of the explosive charges of each blasthole, analyzing the vibration waves produced by each blasthole, allow us to determine the optimal time between the detonation of each blasthole to reduce the vibrations of the production shot. Once the optimal time is found, it is possible also, to predict the vibration of the production shot (considering times and sequences) using predictive models. The waveform recorded includes information regarding the particle velocity and the dominant frequencies of the vibration.

Feb 1, 2020

By Ye Yuan, Jaak Daemen, Shaguo Yuan

ABSTRACT: A 400m2 (480 yd2) heavily reinforced high-strength concrete slab 800mm (31 inch) thick had to be demolished. Underneath it was a 300mm (12 inch) thick underlying structure consisting of three layers: a cushion coat, a water barrier and a concrete layer that protected the water barrier. It was strongly desired by the owner that the underlying structure, especially the water barrier, remain undamaged during the blasting demolition of the reinforced concrete slab above it. This paper discusses the design of the demolition blast, problems encountered, and practical solutions to these problems. First, the impact caused by the charge explosion on the remaining structure was studied. In order to limit crack propagation in the concrete to the bottom of the concrete layer, the concrete isolation layer underneath the bottom of the slab to be demolished was left in place, to protect the water barrier and its protection layer. The effects of blasting vibrations on adjacent concrete were analyzed and precautions were proposed in the design. A safe blast design meeting the requirements to protect the water barrier below the slab was detailed. Rainwater collected and stored above the remaining underlying structure remained in place for two weeks, confirming that the design and blasting were successful.

Jan 1, 2010

By Michael D. McGill, John L. Turner, Don Sieger, Doyle Newhouse

Since its introduction by Atlas Powder Company in late 1986 as a means of highwall stabilization in surface coal mines (1), applications of the basic AirDek (2) blasting technique have multiplied rapidly.

Jan 1, 1991

By Detlef Sulzer, Winfried Rosenstock

"At the end of this century a great breakthrough in the field of blasting technology is finally going tobecome reality. That, in the true sense of the word, is the long expected and desired “HighTechnology Blasting”. So far trials have been carried out in Australia, Africa and Europe with remarkable results, that have been predicted by the authors. As a result, significant reductions of explosives and drilling expenditure are emerging for the future."

Jan 1, 1999

By Raúl Carretero de la Hoz, Leonardo Soares Chaves, João Paulo Soares Toneli, Francisco Felipe da Silva Dantas, Marcos Peres Lopes, Marcus Vinicius da Silva Gonçalves

The mining activity results in environmental impact and thus requires the adoption of techniques to minimize its effects. The rock blasting process is required to break up and move the rock enabling the haulage of the material, however, it might also cause undesirable effects such as flyrock, overbreak, excessive ground vibration or air-blast at the neighboring communities and damage to civil or geological structures located nearby. The Serra Sul mine, commonly referred to as S11D project, has obligations to preserve two natural tropical montane lakes and several maximum relevance natural cavities whose legal preservation radius represents constraints to the mine development and operation. Controlling measures are undertaken to ensure preservation of the cavities, especially during rock blasting stage, with limitations of the maximum instantaneous charge (MIC) and ground vibration control. The demand for high productivity and the large areas with hundreds of blastholes to charge are challenging factors to the charge control. This work presents the development and field application of a map for limiting explosive charges in the rock blasting process at the Serra Sul mine, used for the definition of maximum charges according to the blast location, ensuring the preservation and compliance with the defined ground vibration limits for each cavity. The map is applied at the mine for every blast and when there is a charge constraint, the map helps to define the areas with different charging profiles in the field contributing to higher charging productivity.

Jan 21, 2025

By Erica Lorenzo García, Benjamín Cebrian Romo, Antonio Morato Medina

This paper presents the results of a preliminary study on blast-induced vibrations conducted at a Radioactive Waste Storage Facility, located in Spain. The study was undertaken as a preparatory step prior to the blasting operations required for the construction of a new platform located near critical infrastructure housing very-low, low and intermediate-level radioactive waste. The primary goal was to establish a site-specific vibration attenuation curve to safely determine allowable explosive charges based on their distance to sensitive structures. The study followed the criteria defined in the UNE 22.381-93 standard, which regulates permissible vibration levels for different structural typologies. In this case, the existing facilities were classified as Type III structures, given their heightened sensitivity to vibrations. Two experimental campaigns were conducted. Test 1 consisted of a series of 10 individual blasts with increasing charges, monitored by five strategically placed seismographs to record seismic wave propagation and determine the attenuation parameters via regression analysis. Test 2 simulated a production blast using operational charges of 41.7 kg (91.93 lb), applying different delay sequences (42 ms and 25 ms) between holes to assess wave interference, resonance, and constructive effects. Data analysis showed that the longitudinal component dominated vibration transmission, and the predominant frequencies in the most critical zone ranged between 18 and 20 Hz. Based on these values, a conservative peak particle velocity (PPV) limit of 4.75 mm/s (0.19 in/s) was established for blast design. The recorded vibration levels during the tests remained within regulatory limits, with maximum values of 2.35 mm/s (0.09 in/s) and 2.86 mm/s (0.11 in/s) for the sequenced blasts, and peak acceleration of 0.0464g.

Jan 26, 2026

By Jorge Cárdenas, Luis Huaroc, Máximo Cari, Nestor Delgado

In Peru, after four years of pandemic, some mining companies have chosen to install integrated operating centers in central offices where through network technology and video surveillance it allows them to carry out their activities remotely, this has become a disruptive strategy to promote a safer and smarter mining industry. Our fundamental value is to improve the quality of life, safety and well being of our collaborators, that is why we have created the remote blasting engineering control center " Core" that allows us to humanize mining. Core is an integration of experience, security, technology, quality of life and artificial intelligence; it has media technology connected directly to the mining operation, specialist engineers and technical assistants in team they seek to create optimal proposals of drilling and blasting designs remotely that generate added value to customers. In the planning process the team suggests drilling meshes, in the loading process there are optimized, digitized designs and efficiency in the factory trucks finally in the safety process allows us to identify inadequate pipes within the blasting project, deviation of procedures, remote inspections, identify operating conditions to prevent future risks that may arise in the blasting process. The remote communication systems allow you to monitor mining operations remotely to identify and alert any operational or security deviation that was not identified by the personnel present in the operation, as well as to store images in case investigations are required. The results obtained have allowed us to reduce the exposure of personnel to any risk of the mining operation, to optimize times in the activities of our engineers who are in the mining operations since there is the permanent support of centralized specialists to face every challenge that arises in the operation, for the engineers who are in the offices of Core can be very close to the family and do not lose it, and for our customers it is to meet their needs with engineers specialists in the drilling and blasting process, as well as in safety to be able to proactively cope with any deviation that arises.

Jan 21, 2025

By D Schneider, H Elliott

The advantages and disadvantages of using inclined boreholes in blasting has been under discussion for a long time. Some recognized disadvantages are that drilling costs, both operating and capital costs, are higher for inclined holes than for vertical ones, and that drilling accuracy is more difficult to maintain. People who have used angled holes in practice, on the other hand, have claimed that the quality of blast results was improved. In fact, their popularity has increased, especially in Australia.

Jan 1, 1988

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 Mark Odell, Bruce Northrup

In the hill country of Austin, Texas, Tom Kite has designed a golf course to be built in conjunction with a housing development entitled "Riverplace". The topography in this area is almost solid limestone, which made it necessary to use several types of surface blasting: Pre-splitting, ditch-line, sump shots, not to mention "fairway" cuts and even a sand trap or two.

Jan 1, 1985

By Doug Johnson

This paper reviews the field implementation of R & F Coal's blasting optimization work concerning analysis, prediction, and control of overburden blasting vibrations using site specific measurements and state-of-the-art computer technology. Blasting personnel at R & F Coal had the opportunity to work jointly with Otto Crenwelge of Shell Development Company in his test studies and to later be instructed in the procedures involved in optimizing vibration frequency.

Jan 1, 1988

By A N: Zditovetsky Shishov, M G. Menzhulin

At present in a building industry demand for products from granite, gabbro and other rocks, steady to erosion, natural and chemical weathering, was essentially increased. It has caused the enlargement of exploitation of stone block deposits and necessity of creation of new technologies of hard stone cut.

Jan 1, 1996