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By Carlos Agreda

"It is widely accepted that the rock blasting results are a function of several stochastic variables given by: -The natural geological structure of the rock mass (joint spacings, discontinuities length orientation and characteristics, physical-mechanical properties, such as: ultimate strengths and elastic properties, etc.).-The detonation and explosion parameters of the explosive mixture (V.O.D., P2, T2, Q3, etc.).-The drilling and blasting pattern dimensions.-In this paper the most important stochastic variables regarding with the rock mass and the blast design dimensions before mentioned are identified, described and discussed.A non linear programming method to calculate the optimum burden Bo) is proposed and discussed.The great impact of the stochastic variable called burden (B) on the rock blasting results is emphasized. A comparison between burden theoretical calculations and some field blast results is also shown."

Jan 1, 1996

By Lawrence Mirabelli, William Hissem, Gary Veltrop

Capital Quarries Company, Inc., Jefferson City MO produces aggregate products for road base, asphalt, concrete and concrete block. With their production quantities small in comparison to those produced by the goliaths of the aggregate industry, they find it necessary to constantly stay on the leading edge of best practices for cost control, process and production improvement to sustain a successful business. In the words of Eric Strope, President, “The safety of our employees is foremost. They all work hard each day. They are focused on keeping our cost to manufacture down. As I see it, we cannot work any harder so we must work smarter!”

Jan 1, 2009

By John A. Huber

At an underground limestone mine in the Central United States; there were plans for the installation of a limestone processing plant. The special design and layout of the plant called for the installation of a tunnel from the underground mine to the surface above. The dimensions of the tunnel would be 10 feet high, 20 feet wide, and would be 500 feet long on a 17 degree incline. The tunnel would be used for the transportation of raw stone to the surface by a conveyor. A second conveyor would transport processed limestone into the mine for storage, that would be loaded out for shipment later.

Jan 1, 1995

By Clarence Zink

The need for continual process improvement and innovation to reduce operating costs in the mining industry extends to the first significant encounter all production miners have with the rock: drilling blastholes. Material and design advances alone have greatly increased the productivity of today's tricone blasthole bit over bits used just a few years ago. Significant additional operating savings are being realized by utilizing improved air practices on blasthole drills, and by selecting drilling equipment designed to provide optimum air volume and pressure at the blasthole bit.

Jan 1, 1997

By Alain Blanchier

Because in Europe and in many other countries as well every new project (quarry, mine, public work) needs a risk estimation to prove its feasibility, a model to estimate flyrock risks became necessary. This paper presents the basic hypothesis which should underlay such a model to estimate statistical flyrocks range for not only some single blasts but a whole project and in particular the way to take into account rockmass or blast pattern parameters variability. It describes a first usable quantitative flyrock model based on the characteristics of the blasting plan and of the generic laws utilised in casting and selective blasting operations and on a statistical approach of rockmass. In a second step, this paper discuss an approach of risks estimation compared to the classical one used in pyrotechnics studies for explosive magazine risks assessment.

Jan 1, 2013

By Rob Farnfield, Mike Kelly, Toby White

There are a variety of sources of dynamic stress which can affect a building and give rise to cracking. A two-storey house, situated in the middle of a surface coal mine was monitored for a period of 30 months to attempt to identify the major causes of cracking. The factors described as environmental include internal and external temperature, humidity, wind speed and direction, rainfall and water table level. These were monitored using a weather station and piezometer and recorded every 20 minutes. The other factors are vibratory and include normal household movement (walking, shutting doors etc.), vehicle vibration and blast vibration. All the significant vibrations in the house were recorded using four sets of velocity transducers and accelerometers.

Jan 1, 1993

By Earl C. Hutchison, John Loviza

At the Metropolitan Nashville International Airport, with its more than 600 scheduled daily flights from American Airlines hub operations, other scheduled airline flights, Tennessee Air National Guard operations, as well as numerous industry air flights, the excavation of 300,000 cubic yards of rock was required without disrupting airport operations for a cut and cover underground tunnel with a 4 lane US Highway and new airplane runway to extend across it's top. In addition to the excavation, the removed rock was to be broken to specification type that was clean and of small size for fill in another area of the airport property. The blasting was limited to two 1/2 hour windows per day and stiff monetary penalties were in place for schedule slippage of each phase of the project.

Jan 1, 1992

By Wang Zhong Qian, Liu Hui

The paper proposed a fractal and damage model for rock-breaking by blasting, which assumed that the process of rock-breaking results from intrincent fractal development and the accumulation of damage. Remarkably, the process is of fracture character. Based on the model, a computer program is compiled to calculate the 3-dimension damage distribution in blasting crater. Trial results agree well with the predicted results, showing the model set up in the paper is sound.

Jan 1, 1997

By Anne Charline Sauvage

Blast designers and blasters need to know the rock mass influence on blast to increase explosive effi-ciency and to optimize costs, but also to succeed in limiting blast emissions (vibration, overpressure, flyrock) This paper presents an applied approach which makes it possible to structure the information con-cerning the rock mass and the blasting.

Jan 1, 2013

By Leslie Taylor, W. Fourney, Uli Leiste

This paper presents the results from a series of tests conducted to investigate the total vertical impulse delivered to a target plate by a buried explosive charge. The tests were conducted at a very small scale but previous work has shown that small scale testing can predict impulse applied to plates in full scale. Non-deforming plates were used to determine the change in impulse delivered to targets as a result of changes in standoff distance and burial depth changes.

Jan 1, 2009

By Robert S. Mayo

Tunneling, for transportation, began in France with the Milpass Tunnel on the Lanquedoc Canal in 1680. Of course, the ancient miners had been driving tunnels in search of minerals since the dawn of history but this Milpas Tunnel was the first tunnel exclusively for transportation. In England in 1760, the Duke of Bridgewater opened a canal from his coal mines to Manchester, 10 1/2 miles away. At the mine, he drove a tunnel into the mountain so that the miners could shovel the coal directly into canal boats. James Brindley, an untutored genius, was his engineer and this whole transportation system was an instant success and very profitable through the years. Within a dozen years the Duke, again with James Brindley, opened up the Grand Trunk Canal, 139 miles in length with five tunnels. There was one major tunnel on this system, the First Harecastle Tunnel, 1 1/2 miles in length. But this tunnel was too small. It was only large enough for one 7-ft wide boat which had to be "legged" through by boatmen laying on their backs. By 1824 a second tunnel was driven parallel to the first one, but it had a towpath through it for horse haulage. This was the beginning of the " Industrial Age" and tunnels became a very important part of that era.

Jan 1, 1979

By Martin Chenoweth

The Metropolitan Water District of Southern California (MWD) is undertaking one of the nations largest water management projects. The Eastside Reservoir Project is being built to insure a supply of water to Southern California in the event of earthquake damage to the aqueducts supplying the region. An 800,000-acre-ft lake will result from the three dams, closing off the valley between two parallel ridges. The single largest contract of the project, the West Dam, was awarded to the joint venture of Atkinson Construction Co., Washington Construction Co. (Morrison Knudsen Co.), and HB Zachry Co. Over 50 million bank cubic yards of rock must be drilled and shot on this contract alone. AWZ relies on the TechBASE database management system for documenting drilling and blasting. The database format of TechBASE allows all production parameters to be linked to the location of the activity. This allows parameters such as drill penetration or boulder production to be analyzed for geologic trends that can either be exploited or dealt with. Shot locations are stored as 3D polygons in a polygon table. Production and cost data are stored in flat tables. Shot names are unique and link the polygon table to the flat table. This allows typical database queries to be made by date, location, cost or any production parameter. The output from these queries can be presented in table, graph and as map formats. The map output is particularly helpful in quantifying geologic conditions and blast performance. The ability to transform the data into information has been very helpful. The ability to present this information graphically has been invaluable.

Jan 1, 2000

By Dr. Zach Agioutantis, Elliott Morgan

The explosives, mining, and heavy civil industries consistently battle the uncertainty that is associated with working with a heterogenous medium like rock in blasting. This has led to studies to increase fundamental understanding of material response under dynamic loading that is associated with blasting. This study looks at the dynamic strain associated with blasting the lab Split-Hopkinson Pressure Bar (SHPB) testing while also building off of previous studies with the goal of better understanding the dynamic forces that are enacted on a geologic body during a blast loading event. This is required in order to advance geologic blast response modeling. This is achieved through analyzing the stress and strain values for each specimen that are calculated from strain data collected with a SHPB. Based on this data, the dynamic material response characteristics are able to be determined. Tests were conducted on five Berea Sandstone specimens with a rough length to diameter ratio (L/D) of 1.0. The strain data from these tests were then used to create stress strain curves as well as charts depicting failure stress to both strain rate and failure particle velocities. The tests conducted returned similar results to previous tests results on Berea Sandstone while also showing a correlation between strain rate at failure and failure particle velocities. While further research is needed, there is evidence that SHPB test data could be used in conjunction with the MBF model. The MBF model states that the peak particle velocity (PPV) of blast vibrations can be correlated with deformation (strain) at a given point. With a further understanding of dynamic material response correlated to PPV measurements, further refinement could allow for better prediction of blast performance.

Jan 21, 2025

In this work, is being described the developing of the study for the demolition by controlled blasting project of a building of reinforced concrete, in the center of a spanish city. Synthetically, it is being analyzed the timing of the fall of the parts of the structure. This documentation is completed with a group of four photographs of the falling sequence and a film about several demolitions and the particular one described in this paper.

Jan 1, 1977

By NA NA

None

Feb 6, 2023

By TTE-Europe GmbH

A few years ago, the term Track & Trace for explosives was only known in Europe and Brazil at most; the introduction of this technology is experiencing an undreamt-of boom worldwide. More and more countries are enacting legislation to introduce Track & Trace of explosives and follow Europe and Brazil on this path. At present, the world's leading manufacturers are already using such solutions, are in the process of implementing them, or are in the planning process. However, based on the experience gained in Europe, there are outstanding challenges for all manufacturers. These are questions of compliance, logistics, distribution, and, of course, especially, the necessary adaptation of the production environment. However, this development involves considerable effort on the part of the manufacturers. New devices for marking the explosives and digitally recording the data are integrated into the production process. This should be done as cost-effectively as possible, without restricting production capacity and speed, and with as few process changes as possible. This paper uses real-life customer experiences examples to explain paths from project design to real implementation. Lessons learned from the experience of European explosives manufacturers are presented, missteps are described, and solutions are identified. Individual steps along this path are explained, and solutions are told to avoid pitfalls and bottlenecks. Finally, it refers to the risk analysis and concrete examples in implementing the planning into production. Methods of marking various explosives are shown, and the use of Track & Trace to solve logistics tasks in picking and shipping explosives, including the data exchange with ERP (Enterprise Resource Planning) systems.

Jan 26, 2026

By Qingshou Chen, Paul N. Worsey

It has been recently argued that rock strength has little effect on the final results of pre-split blasting and is of only minor importance when blasting rock in general. However, it can be shown that the maximum borehole separation for optimal perimeter blasting results with constant borehole and loading configuration is strongly dependent on the tensile strength of the rock.

Jan 1, 1986

By Lauren Shields

This paper discusses the application of current fragmentation models for underground blasting, establishes a conceptual fragmentation model for underground operations, and discusses the applicability of the mine-to-mill approach for underground blasting. Additionally, this paper also discusses selected case studies where the mine-to-mill approach is applied to underground mining operations.

Feb 1, 2020

By Bert Bahnson

As farms decrease and subdivisions increase there is a continuing demand for easy and safe silo removal. A few years ago I attended one of the Omni istribution explosive classes and was impressed by a product designed by Omni owner Bill Nixon called the Omni Breach. Its original purpose and main current use is law enforcement; specifically door breaching and tactical operations, with most of the force coming from water using a minimal amount of explosive component. I experimented with various charge strengths on concrete and found that it can be easily shattered with little flyrock or airblast. A neighbor of mine had an old silo within a foot of a barn that he was rebuilding and inquired about its removal. His property was sandwiched between an elementary school and Interstate 40, so I told him that I would do some test shots and if the results proved satisfactory, I would take the job for free to test the following theory.

Jan 1, 2006

By Charles Clark, Mark Mukhija, Jaime Klein

Comminution – the reduction in size of solid materials – is the most energy intensive component of the mining process (Bauer, 2015). It is estimated that comminution consumes around three percent of all electricity generated in the world (Ceecthefuture.org, 2017). On an energy equivalent basis, downstream processing consumes six times more energy than drilling and blasting (Kanchibotla, Sarma et al., 2014).

Jan 1, 2018