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By Charles Joyce, William C. Burkle, Dan Murphy

Rare indeed has a major cross country natural gas pipeline met and surmounted such obstacles as the Iroquois Gas Transmission Line from Canada to Long Island, New York. Of the 370 miles long length a fair estimate has been that 1/3 or 122 miles were across rock country. Spread One, Four and Five were particularly difficult. If is estimated that over 75% of the required blasting was on those three spreads. The term "spread" goes back to the old term of describing a ranch.

Jan 1, 1992

By Shao Li, Chen Zhiming, Wu Jihong

In this paper,powder emulsion explosives,which have high sensitivity and strong detonation force,have been studied by applying emulsion technology to the production of the present powder ones.Under the condition of #8 industrial detonator initiation,the distance of air gap propagation is 110~180mm,brisance !3.5mm, lead block test value 325ml and detonation velocity 3000~4000m/s for small diameter (35mm) explosive cartridges.In addition to these,the factors effect on are investigated by experimental study and theoretical analysis.

Jan 1, 1991

By Carlos Agreda

The rock blasting environmental impacts such as: flyrock, groud vibrations,airblast,and/or noise, dust and fumes are identified and mentioned. Some comments on the correction factors that might be taken into consideration to calculate the initial velocity and the maximum projection of the rock fragments are mentioned as well.

Jan 1, 1995

By Calvin J. Konya

For proper blast design, one must make the assumption that all blastholes release nearly ideal energy. In many types of blasting operations, blastholes release very little useful energy. These blastholes are called malfunctioning blastholes. Recent studies indicate that as many as 30 percent of all blastholes are malfunctioning. These malfunctioning blastholes are not an unusual occurrence.

Jan 1, 1988

By Eduardo Berger

This paper describes a mechanized loading system, the HYDRODOSE, which allows the use of pumpable emulsions in underground mining. It also describes a pumpable emulsion explosive for small diameter holes, HYDROMITE PDB. Included are test results carried out in two Chilean underground mines.

Jan 1, 1991

By E Emery Gray, Gary Ard

Each year when hundreds of Engineers and Specialists in the explosives industry meet for the SEE Annual Conference, new ideas are exchanged and new business relationships formed. Harbert Construction Corp. and EGA, Inc., a company specializing in drilling and bIasting, formed such a relationship through mutual interest in such a manner.

Jan 1, 1981

By T Michael LeBlanc

Drill trajectory deviation is a recurring problem in vertical retreat stoping operations. As a result of this deviation, 60 kilogram (165 millimetre diameter) and 103 kilogram (302 millimetre diameter) explosive charges are routinely detonated beyond ore/waste contact zones. Consequently, there follows a reduction in finished stope wall stability and an increase in ore dilution.

Jan 1, 1996

By E W. Kohler

Geophysical wireline logging of blastholes provides useful geological data and has considerable potential to improve overall blasting control and costs. This paper uses case histories to show how logging techniques have highlighted certain problems, and discusses the various in-hole tools available. In particular, the issue of the effects of hole diameter on explosive column height,and the importance of this when deck charging is addressed. The suitability and cost-effectiveness of currently available logging technology to the wide range of blasting applications is discussed.

Jan 1, 1988

By Dale Preece, Stephen Chung, Richard Jensen

DMCBLAST_3D is a three-dimensional extension of the proven two-dimensional rock blast modeling code, DMCBLAST. DMCBLAST has been under development since 1987 and has successfully predicted the physics, mechanisms and results of a number of different types of rock blasting including, coal mine bench blasting, mineral mine choke blasting and underground stope blasting. Substantial effort has gone into the qualification and verification of DMCBLAST by comparing computer code predictions with real blasts in the field. Comparison with field data has also provided significant guidance to the development of the code.

Jan 1, 2001

By Mark S. Stagg, Stephen A. Rholl

The U.S. Bureau of Mines has developed computer software which uses fast Fourier transform (FFT) techniques to evaluate blasting data. The software is useful because it allows blasters to evaluate 1) the frequency content of ground vibration time history data; 2) the effects of initiator scatter on the frequency spectra of ground vibrations; and 3) the fragmentation distribution of rock muckpiles from photographs. A one-dimensional version of the software was used in the first two cases. Monte Carlo techniques were used to simulate the scatter of initiators.

Jan 1, 1995

By Jeffrey A. Straw, Joseph P. Jr Shinko

Ground vibration produced by blasting operations within South Florida, due to saturated soil conditions, generates surface vibration waves that may be measurable over distances of 3 - 5 miles from the source, and perceptible at distances of up to 2 miles. Structures above ground usually receive the most of the attention from the effects of high vibration levels. During construction of the Trilogy Development of the Swerdlow Companies, blasting was completed in a lake excavation immediately adjacent to the City of Pembroke Pines Utility Department, Deep Injection Wells No. 1 and No. 2.

Jan 1, 1994

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 Ruilin Lang

This paper presents an application of 3-D plots and non-linear regressions to define a sitespecific form of the charge weight scaled distance. The PPV (PPA) of single hole blasts is normally considered as a function of two independent variables - the charge weight and the distance. It is of great importance to obtain the relationship of the function accurately for a concerned site in terms of blast vibration analysis and modeling. However, in pre-computer time it was difficult to plot 3-D graphs. Consequently, a charge weight scaled distance was used to plot the PPV (or PPA) against the scaled distance as 2-D graphs. Blast vibration investigators use several forms of the charge weight scaled distances to plot data. We can exemplify them with the cube root of charge weight scaled distance, the square root of charge weight scaled distance, and other forms (Hossaini and Sen, 2004). Each of these scaled distances assumes relative contributions of the charge weight and the distance to the vibration attenuation. For example, the charge weight is assumed to have a less contribution to vibration in the cube root scaled distance than it is assumed in the square-root scaled distance. In reality, for different sites the relative contribution of the charge weight and the distance may be different and site-specific. This may explain that in some cases, the blast vibration data plots using these charge weight scaled distances are scattered. This could be largely due to the fact that the definition of the form of the charge weight scaled distance is not adequate for the particular site condition.

Jan 1, 2006

By Jeff Gore, Jack Dermody, David Gribble, Brett Macaulay, Bart Sharpe, Paul Klaric, Paul Thornley, Ben DeVries

Optimal Fragmentation in Block Caving is difficult to achieve as it is generally defined by the rock mass itself and the way in which the cave is initiated. The lower portion of the cave has even less chance as the material has little time for self comminution. Blast Preconditioning of the Block Cave is designed to engineer the lower section of the rock mass to produce material of a suitable size to assist in the initial cave propagation and improve initial drawbell productivity. At Cadia East a plan was developed to drill 150-metre long, vertical up-holes from the undercut level and blast them fully confined to produce fractures in the rock mass. The blast itself was a simple undertaking. However, in the year preceding the first production blast, all aspects of the process were designed, tested and refined across multiple trials. As this type of challenging application had not previously been encountered in Australia there were many unique situations to address. Products and systems had to be developed and adapted to overcome these challenges. These included: Formulating and manufacturing an explosive that is robust and of a high VoD; designing and manufacturing easy to use electronic initiation systems; and, designing pumping systems to combat high head pressures to allow for successful and safe loading of the holes. Close collaboration with the customer ensured that the trials culminated in successfully blasting a hole containing almost 3.3t of explosive. These trials have since led to the blasting of four holes instantaneously, which contain almost 13t of explosive. This paper describes the various components of the system, the challenges and the final result.

Jan 1, 2013

By Saeed Karimifard, Saman Nouranian, Shahram Tafazoli, Bahram Sameti, Frank Chu, Caitlin McKinnon, Tetiana Konstantynivska, Glen Turner

We propose a particle size analysis solution for haul trucks that does not impact current operational workflows. Using artificial intelligence (AI) and 3D imaging technology, our solution reliably localizes and identifies haul trucks as they drive by, then accurately calculates the particle size distribution of the visible material in each truck load. In this paper, we identify the challenges of designing and implementing the proposed solution and explain the strategies we employ to overcome these. We also discuss a method for boulder detection that leverages the existing deep learning architecture to significantly reduce crusher downtime caused by oversized rocks

Feb 1, 2020

By Natalie Zeleznik, Brian Hawkins, David Bradley, Rachel Gooding, Patrick Wilson, Brian Somes, Kevin Wegman

"To perform a probabilistic risk assessment (PRA), a method of quantifying the risks associated withinfrequent high consequence events, consequence models that generate representative estimates of human health consequences for a wide variety of representative scenarios are commonly used. Criteria that suitable models must possess include: (1) input requirements necessary to generate large volumes ofprobabilistic simulations; (2) the capability to output injuries with the necessary details and resolution;(3) the ability to capture the variety of different scenarios inherent in an assessment; (4) acceptable cost and computational requirements; and (5) sufficient stakeholder buy-in for community acceptance."

Jan 1, 2017

By David Lilly, Robert Ethier, David Bremer

The Lafarge Ravena Cement Plant in Ravena, New York demonstrated continuous and extraordinary improvement in productivity during the past several years. The factors driving continuous improvement at the Lafarge Ravena Plant include: 1) Management techniques including regular scheduled and effective Blasting Optimization Team meetings. 2) A real time blasting database to guide blasting product and procedure decisions. Key decisions involved all levels of quarry and blasting supplier personnel and a close working relationship between production and blasting areas of expertise was demonstrated. 3) Blast optimization and optimization of quarry operating parameters such as blast location relative to crusher location, hours worked, etc.

Jan 1, 2007

By Dale Ramsey

Located in the Chestnut Ridge Mountains of Southwestern Pennsylvania, the Casparis mine named for the founder Kenneth Casparis operated from 1916 until the early 1950. producing crushed stone for construction and railroad ballast. The rock was transported by aerial buckets to a railroad tipple nearly 1000’ (304.80 meters) below the mine. The mine property is now owned by the Pennsylvania Game Commission and is located in the Loyalhanna limestone seam with 4 primary entries that are approximately 40’ (12.19 meters) high by 30’ (9.14 meters) wide and extend over 2 miles (3.22 kilometers) into the mountain.

Jan 1, 2006

By Shih Wen Wang, Ronald R. Rollins

A blast casting model is proposed to predict the burden velocity in bench blasting. This blast casting model is the first theoretical model that 1) explains the throwing procedures and mechanisms, 2) uses the explosion pressure as the primary source in throwing rock fragments, 3) applies them to field conditions successfully. Also the predicted burden velocities are based on the rock properties, the explosive properties, and the drilling and initiation patterns. This blast casting model is programmed into a computer software "ROCKFRAG". The comparisons between "ROCKFRAG" predicted values and two field test data are in good agreement.

Jan 1, 1992

By Dae-Woo Kang, Sang-Wook Kim, Shin Lee

The Air-tubes blasting method is provided in which a series of aligned boreholes are charged with explosive s and air tubes in a predetermined blasting pattern. The air tube is composed of cylindrical flexible tubes which have a predetermined width and length to be fit with the site boreholes. Within a preferred formation, each borehole is charged with the explo sives and detonators with an air tube installed just above the explosives. Stemming materials are filled above the air tubes. At the limestone mine of Sung-Shin Cement Co., in South Korea, these blasting tests were performed by a diameter 102 millimeter and 15 m long boreholes with the charging length of explosives was 8m to 10 m by the total weight of explosive 40 to 50 kg with 3m to 6m air tube which has a 76 mm diameter, and 1m to 3m stemming cover. Blasting results showed the about 10% to 30% explosives savings available and especially, the about 20% to 50% reduction of ground vibration with the low noise measures around 2dB to 5dB by this new blasting method which was compared with the conventional blasting methods. The explosives and air tubes may be alternately charged along the boreholes. The use of air tubes which were charged above an explosive layer allow to form the quantitative air decking in every blast hole. Therefore, the Air-deck effect can be easily obtained through this blasting method, and also easy to increase the fragmentation rate resulting in the more suitable mucking procedures at the working site with the minimum usages of explosives for the better economic operations in mine quarries.

Jan 1, 2005