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By Ery Wardhana, Stefanus Jagad, Relinda Sanistya, Hasucita Tausi, Rido Situmorang

The blasting process is one of the most high-risk activities in mining operations. Shotfirers and blasting crews face hazards from slope failure, toxic gas and fumes, or unstable ground condition every day of the blast. But on the other hand, to ensure all of the holes are detonated, shotfirers are required to reenter the location to check. With advances in technology, nowadays the use of drone in mining is not something that is rarely seen. It has been used for mapping and slope-monitoring. This paper will discuss the application of drone for blasting process in a mining pit in East Kalimantan, Indonesia. By using drones, it is not only safety factor which can be improved but also operational efficiency and technical analysis. The duration it takes for post blasting process can be reduced because the drone can directly enter the location after blast. The technical analysis for the blast can also become more comprehensive, as the before-after photos and video documentation can be taken with wider view. It helps with fly rock calculation and fragmentation analysis too.

Feb 6, 2023

By Norman S. Smith, Troy D. Harris, Richard L. Ash

In open-cut bench blasting drilling boreholes below grade level is normally considered essential to insure toes do not remain. The extra drilling and use of explosive below floor level are not only expensive but on occasion cause serious problems including severe floor damage and excessive ground vibrations. It has been reported that under certain circumstances explosive in the subdrilling has been successfully substituted by broken rock with its associated benefits.

Jan 1, 1978

By Lina Lopez, Jose Sanchidrian, Manuel Lopez, Pablo Segarra

Previous work in which rock properties and blasting parameters (geometry, charging and timing) were reported together with truck filling times, is taken as a starting point for a thorough analysis of the influence of the former on the mucking velocity. The experimental set was composed by 11 blasts made in an open pit mine. Non-parametric, distribution-free statistics is applied. The mucking rates (in bank cubic meters per unit of bucket volume and per hour) appear to be clearly dependent on the explosive energy and powder factor, both magnitudes combined as energetic powder factor (energy per unit of rock volume). The mucking rate is a non-monotonic function of such factor in the range of the blasts analyzed. The determination of the function is optimum when the fraction of the explosive below grade is not considered and when the explosive energy is qualified as that delivered at a partial detonation regime. Different types of loaders seem appropriate for different energy levels. At low levels both front loaders and rope shovels obtain small productivities without a statistically significant difference in their performance. At high energy levels, front loaders qualify higher than rope shovels. Mucking velocities can be equally small at low energy powder factors and at high ones if rope shovels are involved.

Jan 1, 2008

By Joshua Hofman, Braden Lusk, Erin Morris

Explosions in urban environments, whether of accidental or malicious cause, often result in extensive injuries, loss of life, and property damage. The ability to predict the damage inflicted by these events is highly sought after; in order to predict damage, the behavior of blast waves within these environments must be quantified and understood. Urban constructs such as buildings and roadway intersections affect the natural propagation of a blast wave, intensifying or rarefying the wave depending on their arrangement.

Jan 1, 2012

By Gungor Tuncer, Ali Kahriman, Umit Ozer, Abdul Karadogan, Mehmet Aksoy, Ertugrul Kaya, Deniz Adiguzel

This research was performed on the quarry that will be opened to produce aggregates and rock filling material at Catalagzi region at Zonguldak providence. Excavations will be done by drilling and blasting. However, there are some structures which can be adversely affected by blasting at the quarry. These structures are a methane exploration drill hole and a house at the distances of 340 m and 390 m, respectively. The one of the main goals of this study is to perform a preliminary assessment of possible damage effect of ground vibrations induced by blasting on these structures by risk analysis based on ground vibration measurements.

Jan 1, 2009

By John Platt, Mark Stephens

"When blasting is required in critical areas and anticipated shot movement and quick cleanup areessential to the success of the project it is extremely important to use the best technology available to achieve the goals expected by the customer. Wampum Hardware was given such a challenge in 2014-2015 when the PA Turnpike and New Enterprise Stone and Lime hired the company to do presplit blasting along the PA Turnpike. The face height averaged 45 feet (13.72m) and the shots had to be controlled to stop within 60-75 feet (18.29-22.86m) of the face or in this situation before they entered the travel lanes on the PA turnpike. In many if not most blasting environments, it is essential in controlling the movement of a blast, to make certain that the face holes are drilled at exactly the right place, with the proper amount and type of burden in front of and to the sides of the borehole. Profiling is an important first step to insure that the holes are drilled at exactly the right place and showing us the correct amount of burden in front of each and every drill hole."

Jan 1, 2016

By Dale S. Preece, Stephen H. Chung

"In bench blasting, the distribution of loaded explosives with respect to the burden rock has strong effects on digging especially at the toe area. Blast design often focuses on other results such as percent-cast or fragmentation, sometimes leaving a diggability problem at the toe of the blast that is not discovered until excavation. A method for assessing the influence of blast design on diggability has been developed. This method relates the kinetic energy and rock displacement experienced by the material in the muckpile to its diggability. Simulation of the blast along with the calculation of kinetic energy and diggability is done with the discrete element computer program DMC_BLAST(DMC: Distinct Motion Code)."

Jan 1, 1999

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 R Holmberg, P A. Persson

Recent developments in the methods of measuring rock motion close to the contour at the moment of blasting have given an improved understanding of the extent of rock damage caused by different charge systems. The paper presents the new results and the methods of prediction of damage zones which are used in Sweden for the design of contour blasting rounds. A survey is given of the tools and the techniques for smooth blasting that are now used on a routine basis in Sweden.

Jan 1, 1978

By O E. Jr Crenwelge

Recently promulgated regulations governing blast induced ground vibrations in the mining industry contain a frequency criterion as one option for verifying compliance. This criterion is based upon an oversimplified method which assigns the entire peak particle velocity amplitude to one frequency. Depending upon the nature of the vibration time history, it is possible that this frequency may not even be one of the predominant frequencies of the signal. In addition, the criterion does not specifically define the data analysis approach to be used by the industry for obtaining either the amplitudes or the frequencies of the vibration components. And because personnel in this industry generally have little understanding of vibration phenomena, a number of different approaches are currently being used for satisfying the criterion. This paper presents a method for obtaining both the Fourier amplitude-frequency spectrum and the integrated predominant amplitude-frequency components for the vibration record. The method is both physically and mathematically correct and is in common use in a number of other industries. Therefore, it should be of help to regulators, blasters, and consultants charged with developing, enforcing, or implementing ground vibration criteria.

Jan 1, 1988

By Charles G. Wade

In the ensuing years nitroglycerin-based dynamites will continually be replaced by water-based explosives. Until recently, the choice of a high explosive water-based product was limited to some type of water gel. Now, there is another choice. New emulsions are available having several degrees of sensitivity over a wide range of diameters. This paper discusses the properties of these new emulsions, e.g., physical and thermochemical; the relationship between diameter and explosive properties; and the effects of aluminum on total energy. There is also discussion of some of the unique properties of emulsions, their advantages, and how they differ from water gels.

Jan 1, 1978

By Dale Preece, Stephen Chung

Development of DMCBLAST-3D is continuing and now includes the capability to simulate the detonation of multiple blastholes in multiple rows that make up a conventional bench blast, either in a rock quarry or a surface coal mine. DMCBLAST-3D is a three-dimensional extension of the proven twodimensional 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, 2002

By Pierre Mousset-Jones, Geraint W. Harris, Robert Karlin, Jaak Daemen

In order to minimize the ore dilution induced by blast movement in surface mines it is necessary to quantify such movement. This will make it possible to more accurately locate the grade boundaries on the surface of a blasted rockpile prior to excavation. This paper describes the development and testing of a method to accurately measure the direction and magnitude of sub-surface blast movement. The technique involves the use of magnetic "radiometry, using a cesium vapor "radiometer and real-time differentially corrected, GPS system, to locate the post-blast position of magnetically enhanced target objects, whose pre-blast locations are known, without disturbance of the blasted rock. The objective is to design an accurate and efficient technique which can be integrated into a mines production cycle.

Jan 1, 1997

By J P. Tidman

The problem of blasting fragmentation has received a good deal of attention in recent years. Progress by the scientific method requires a good set of experimental data as a benchmark to test models. Recent models have become so complex that it is not possible to use the results of field data because the complete set of parameters needed to describe the rock and/or explosive are not available.

Jan 1, 1991

By D. Goodings, W. L. Fourney, Bonenberger, R., Uli Leiste

The problem of the maximum depth at which a mine buried in the surf zone or beach zone is a threat to landing vehicles is being studied by Naval Surface Warfare Center (NSWC), Indian Head Division, Naval Research Laboratory (NRL), and The University of Maryland Dynamic Effects Laboratory. The problem was divided into two parts: The first part involves determining how deep a pressure plate mine can be and still detect a vehicle passing over it. This requires determining the distribution of stress within dry and saturated sand when a vehicle passes over a buried mine. The results obtained from that study are presented in a related paper (1). This paper will cover the second part, which entails determining the impulse delivered to the vehicle. This is equivalent to determining the impulse delivered to a plate suspended above the detonating explosive charge and includes an investigation of the distribution of the impulse over the plate. The purpose of the research is to develop a scaling law and/or computational capability which will permit predicting impulse to be expected in the field from tests conducted in the lab. The computational effort is aimed at the development of and confidence in computer codes that can be used to predict stresses and strains in plates due to the detonation of buried mines.

Jan 1, 2004

By G J. Kulbieda

The Empire Mine initiated production in 1963. Since then the unit operations of drilling and blasting have evolved continually in order to meet the increased mining requirements demanded by plant expansions in 1968, 1973 and 1980. Additionally, advance mine planning has become an integral part of proper pit development and is necessary to insure uniform blending of the distinct ore horizons contained within the mine area. Blasting practices have been modified to facilitate the autogenous grinding system utilized at Empire and pioneered in the Iron Ore Industry. Technical innovations in the explosives industry, as well as, progress regarding on site blast engineering methods have substantially increased the use of ammonium nitrate explosives and helped to establish efficient charging procedures. In addition, the recent introduction and use of ammonium nitrate fueled with nitropropane and methanol indicates that it is a viable substitute for aluminized ANFO.

Jan 1, 1981

By S A. Steyn, I P. Douglas

Duvha Opencast is a large South African dragline operation supplying coal to the Duvha Power Station which is operated by Eskom, the state power utility. For Duvha to remain competitive with other collieries, it has proved necessary to continuously examine and investigate methods of reducing costs. With explosives representing a major portion of the total working costs, blasting is an obvious area of investigation.

Jan 1, 1991

By Ankit Jha, Sudarshan Rajagopal, Purushotham Tukkaraja

Geologic structures are one of the crucial parameters in blast design. Structural geology and rock properties influence drilling patterns, blast layout, and initiation systems. A comprehensive understanding of structural characteristics is essential to achieve the desired blasting objectives. This paper aims to identify geologic features in a bench using images obtained from the drone. Images obtained from mine site are annotated for geological features such as faults and joints. Semantic segmentation of images is achieved using an encoder and decoder structure available in the machine-learning pipeline. The encoder consists of initial convolution and pooling layers to capture essential features of the geology and rock patterns from two-dimensional RGB images. Batch normalization is used to put all the features on the same scale. These images are then inputted as training data for the machine-learning algorithm. Machine learning model is trained on sub-section of interest to achieve reasonable accuracy. Initially, 1000 best annotations were used to train the model and additional samples were added later to achieve more accuracy and avoid iteration of machine learning model in wrong convergence. After the model achieves reasonable accuracy, it is used to recognize geological features on new data. Geological features identified on the new data can be used by the blasting crew in blast design and keeps the geological maps updated that can help the geotechnical team.

By D P. Proudfoot, S G. Keith, D P. Onagi

A number of aspects of the Canadian concept for nuclear fuel waste disposal are being assessed by Atomic Energy of Canada Limited (AECL) in a series of experiments at its Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, Canada. One of the major objectives of the work being carried out at the URL is to develop and evaluate the methods and technology to ensure safe, permanent disposal of Canada's nuclear fuel waste.

Jan 1, 1996

By Michael Wieland

Delay blasting in underground coal generates shock waves and rifting forces that damage charges remaining in the blast pattern. Damaged charges detonate poorly, raise fume toxicity and reduce coal breakage. Such circumstances could be prevented by using explosives resistant to cross-hole interaction damage. The design of rugged explosives is fraught with contradictory requirements, but tradeoffs related to hard-particle size characteristics prove useful. Hard particles, related voids or trapped bubbles represent reaction nucleation centers which strongly influence the performance of coal mine explosives.

Jan 1, 1992