Search Documents

By Enver Alan

This Research & Development (R&D) study was conducted in the field of applied blasting engineering in Ethiopia, within the AKH Railway Project, which was built in Girena, within the boundaries of the province of Mersa, in the Basalt Quarry at km 346, Ashangi Formation, occured in Eocene geological time in the aphanitic trachibasalt.

Feb 1, 2020

By Adrian J. Moore, Alan B. Richards

Responsible blasting requires that rock throw be controlled to ensure that no danger will result to people and property. This paper describes the development and testing of empirical field calibrated formulae that can be used to evaluate rock throw, provide an early warning of when reduced burden will endanger people and property, and prevent flyrock incidents. Inputs to the formulae are charge mass, burden or stemming height, and a site constant that lies within a general range that can be tightened by site calibration. The output is the distance that rock will be thrown, and this ‘design your own flyrock’ quantification can be used to establish both safe clearance distances, and the critical range of burdens and stemming heights where the situation changes rapidly from safe to hazardous. Examples are given of the use of the model to control flyrock in open-pit mining and quarry operations, in situations which are controlled by both burden and stemming height.

Jan 1, 2004

By P McConnell, T Garrigan

Tara Mines Limited, in Ireland, is Western Europe's largest zinc mine. Annual metal production, from 2.5 million tonnes of ore, consists of 180,000 tonnes of zinc and 34,000 tonnes of lead.

Jan 1, 1989

By Nikolaos Petropoulos, Ulf Nyberg, Daniel Johansson

A series of signature boreholes were blasted to observe any difference between confined and free face blasts. Four geophones were used to capture the compressive wave. The conventional approach, i.e. the calculation of vectorized peak particle velocity (vPPV) did not show any difference. Also a wavelet transform was tested.

Feb 1, 2020

By Viktor Aranovich, Thomas E. Brown

The Almalyk Integrated Mining and Metallurgical Plant is located near Tashkant in Uzbekistan and is one of the former Soviet Union's largest copper producers. Almalyk consumes about 10,000 metric tonnes of explosives annually and expects this requirement to double by the end of the century as they implement a program to boost mine output.

Jan 1, 1998

By Alan Hooper, James E. Mischler

Construction began in 1984 for a 5 megawatt hydroelectric power retrofit at the O'Shaughnessy Dam for the City of Columbus, Ohio. The construction necessitated excavation of limestone bedrock up to 27 feet below the normal water level of the river downstream of the dam. Proximity to the river and difficult terrain resulted in an interesting and challenging construction project.

Jan 1, 1986

By Lynn Long

We have seen many new developments in the explosive and blasting accessory category, but one of the most useful items is the blast control plug. Blast control plugs are cone shaped units that are placed in the stemming just above the explosive load. They are placed about 8 to 12 inches up into the stemming material.

Jan 1, 1996

By Jerry Wallace

Two recent-release boulders posed serious threats to public transportation and utilities in Washington State. Both required challenging drilling and blasting solutions.

Jan 1, 1997

By Catherine Johnson, Kelly Williams

Advances in high-speed video imaging make it possible to see the refraction of light due to the high-density gradient at the shock front without the need for parabolic mirrors or additional light sources necessary for Schlieren or shadowgraph imaging. The average shock front velocity between two points can be calculated by dividing the change in position by the elapsed time between the images. Using the Rankine-Hugoniot relationship demonstrated by Swisdak the peak overpressure of the shock wave can be calculated from its velocity eliminating the interference of the gage and mount

Feb 1, 2020

By Sebastián Seria, Jorge Álvarez, Diego Cáceres

The capacity to break the rock into adequate size fragments and in a cost-effective way is one of the main challenges in large open pit copper mines in Chile. That capacity is often compromised by the accuracy of geological estimations and the resources allocated by the mine site to update those models, making the blasting design highly dependent on that input and in consequence, blasting results. Given these opportunities, having an alternative method to input estimated key geological parameters allows blast designers to modify their designs and apply the appropriate energy to achieve the desired results. By using measurement-while-drilling data from boreholes and a few samples of actual, widespread, hardness measurements on site, we can deliver an updated cost-effective hardness estimation that is used as an input to improve the blasting design and its results on fragmentation. This estimation is delivered as a hardness interval – often in MPa units- related to the position of actual drilling measurements. In addition, having a sufficiently large drilling dataset allows us to predict hardness in new, undrilled areas near already measured boreholes, serving as a prior estimation available before pattern design. The use of these estimations, applied to several copper mines in Chile, allow us to more accurately determine explosive amounts and borehole drilling, which directly contributes to more productivity and efficiency in mine site operations. The results are often related to narrowing the gap for fragmentation results, even so, in some cases that will be related to direct savings in Drilling & Blasting process in a range 5-10% of the budget, due to powder factor changes.

Jan 26, 2026

By M. S. Dotto

The knowledge of the explosive/ rock mass interaction process is important in predicting blast performance. It includes understanding rock properties, energy usage, and attenuation in the rock mass. The paper proposes a method to quantify blast-induced rock mass damage from the field measurements and apply it to modeling blast fragmentation.

Feb 1, 2020

By Yogesh Narula

Nevis Bluff Landslide - On September 17” 2000, a rockfall measuring lO,OOOm3 at Nevis Bluff, New Zealand, triggered a loday emergency. It ended when a hazardous column of rock that towered over State Highway 6 was finally shattered. The operation called for unusual and unique solutions using aerial bombing and inverted blasting techniques, not known to have been attempted before under these conditions, anywhere in the world.

Jan 1, 2002

By Ronald W. Roberts

For years, blasters have experienced near-misses, injuries, and yes, even fatalities as a result of the dangerous nature of our business. Yet, some blasters continue to portray the immortal attitude: nothing-would-or-could-ever-happened-to me syndrome. As we all know, that attitude can become disastrous to yourself or colleague(s).

Jan 1, 1996

By Nikolaos Petropoulos, Changping Yi, Daniel Johansson, Håkan Schunnesson

The effect of jointing on fragmentation by blasting was investigated experimentally and numerically. Firstly the experimental results were presented. Then the numerical modelling based on the experiments was performed. The same conclusions can be obtained based on both experiments and numerical modelling.

Feb 1, 2020

By Douglas Bartley

As the economy continues to slowly recover, our industry continues to finds ways to increase productivity while being forced to cut costs. The drilling and blasting process is the starting point of any aggregate or mining process. Many people refer to it as the “Primary Crusher” as it will always be more efficient to crush rock with explosives energy than it will be mechanical energy. It is the more efficient use of this energy that is addressed in this paper.

Jan 1, 2012

By Pavel A. Torres, Darwin Torres, Sandro Huaman

Given the limited efficiency of blast-induced ground vibrations prediction empirical models, due to the complex geological system from a Peruvian mine. An artificial neural network was built in order to get better results. More accurate and precise predictions allowed the generation of blasting domains for future designs and decision making.

Feb 1, 2020

By Darío Innamorati, Jorge Oliva

Cerro Vanguardia is a known gold and silver deposit located in the province of Santa Cruz, Argentina. The mine has been in operation since 1998 and is thought to be one of the most important mines in Patagonia. More than 102 epithermal quartz veins have been identified in the area, with variable lengths, thicknesses, orientations and dips that constitute what is possibly one of the most extensive outcropping vein systems on earth. Veins are vertical and have variable depth. For this reason, the deposit is currently mined with a variety of extraction methods. This operation is made up of more than 60 open pits and 20 underground access ramps to exploit the deepest high grade narrow veins. This study is focused on the combination of underground exploitation with open pit blasting. That is, those production stopes in the upper levels of underground mines and their interaction with the damage levels in the final slope of open pit mines, as well as in the study of the impact of the generation of vibrations from the blasting of open pit mines and their influence on underground mines. Considering the current stage of the mine, after 20 years of operation, Cerro Vanguardia faces the need to mine deeper deposits in the face of increasing costs and declining grades. For this reason, it is essential to study the interaction of these exploitations. From a personnel safety point of view, this interaction must be well coordinated so as not to affect people and equipment. Likewise, the generation of vibrations due to blasting must be studied, which would produce new cracks, potentially generating overbreak and dilution. The main objective of this study is to determine the possible causes and influences of the blasting interaction in open pit and underground mines, seeking an optimization of the blasting process and a safety standard for personnel and equipment. To achieve these goals, this study includes a vibration monitoring plan to analyze the charge performance and determine rock constants. With the use of specialized software, damage modelling and simulations are used to determine values of damage in order to reduce overbreak. In addition, this plan contemplates the estimation of flyrock in blasting where underground work is connected to the surface, determining safety distances when carrying out a blast.

Jan 21, 2025

By Ruilin Yang

Kinematic approach of blast modeling refers to using the velocity, strain, or displacement as controlling parameters to model blasting, rather than the stress and the material constitutive relations. The rock stiffness or constitutive relations is very hard or impossible to obtain due to the complexity of the rock mass property.

Feb 1, 2020

By S B. Richardson, D Mead, N T. Moxon

The use of air-decks to reduce explosive costs has become very topical in recent years. The majority of the research in this area has been arried out between the Soviet Union where reductions in explosive consumption of between 10-30% have been claimed with apparent benefits being gained in both fragmentation and movement. Work carried out by the University of Maryland using thick plexiglass blocks has supported these findings and indicated that air-decks in measetbe duration of action of the shock wave on the surrounding material by a factor of 2 to 5 (see Figure 1). Although the fracture network resulting from this mechanism is not as intense as that produced adjacent to the explosive charge it does appear to act over a larger volume of material. Although the mechanism attributed to air-decking has been studied in some detail the effect of this mechanism on the size distribution of material produced during a blast does not appear tot have attracted much attention.

Jan 1, 1991

Controlled Blasting, Inc. (CBI) located in Norcross, Georgia recently teamed with the Dekalb county fire marshals office to stage a mock disaster to test new trainees of Community Emergency Response Team (CERT). It as an interesting example in which industry can help out the community and government through the use of explosives.

Jan 1, 2010