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By Agus Setiabudi

East Pit Wira II Project in South Kalimantan, Indonesia with a radius of <500 meters (1,640 ft) from residential has about 454,168 tonnes of coal reserves, with a total remaining reserves of 3,369,383 tonnes (topography per end of June 2011). Thus, reserves may be lost as much as 13.48%. Therefore, it is needed to determine safe blasting technique which meets the Indonesian National Standards (SNI) No. 7571:2012 of vibration threshold, the maximum vibration of 3 mm/s (0.118 in/s) and air blast of 120 dB.

Jan 1, 2014

By Dwayne Tannant, Jeffrey Loeb

Blasting techniques and protective measures exist that can mitigate risks associated with flyrock and the nuisance of vibration, and overpressure. However, these are often misused or not used because there are no prescriptive regulatory requirements and typically urban blasting guidelines do not exist. The relationship between the increasingly negative publicity that the urban blasting industry receives and the existing state of regulatory control on blasting in urban environments is presented.

Jan 1, 2012

By Curtis Garner

Griesemer Stone located in Springfield, Missouri has supplied aggregate in Southwest Missouri since 1946. In 1954 the decision was made to mine the formation and utilize the mined out area for warehouse space. As advancement proceeded, entrances and small diameter air shafts for ventilation were needed and had to be added. It was decided in 1989 to sink an 8' diameter air shaft designed to move 200,000 cubic feet of air per minute with the help of (4) four 50,000 CFM Loren Cook Fans.

Jan 1, 1991

By J R. "Dick" Daniel

Over the past several years, the Hercules Technical Service Group for the Explosives Department has produced a series of programs for the TI59 programmable calculator dealing with explosive application problems. These programs have been made available to both our internal staff and to the Hercules explosives distributor organization. Several of these programs have found good acceptance and wide usage.

Jan 1, 1984

By Mark S. Stagg, Steven V. Crum, Stephen A. Rholl

As part of its ongoing research concerning rock fragmentation by blasting, the Bureau of Mines has undertaken a series of test blasts where six cylinder-shaped pieces of granite rock were fragmented using high explosives. The tests were intended to: 1) Establish a dataset that could be used in the development and verification of theoretical models that simulate rock blasting and 2) To add to the fragmentation data currently being collected by Bureau researchers. The cylindrical geometry was chosen so that the fragmentation could be directly compared to two-dimensional computer simulations that assume an axisymmetric configuration as well as more sophisticated three-dimensional models. The granite cylinders, Carnelian granite and Charcoal granite, ranged in size from about 0.46 meters (18 inches) to 0.58 meters (23 inches) in diameter by 0.91 meters (36 inches) to 1.52 meters (60 inches) in length. Physical rock properties tests performed on the Charcoal granite cylinders indicated that the rocks did in fact have similar physical characteristics. PETN-based detonating cord and dynamite were used as the explosive charges and estimates of the values of some important physical properties are given. For the first five tests, the blasted rock was contained by a heavy rope mat suspended inside the Twin Cities Research Center's blasting shelter. The fragments from each of these shots were sorted and weighed to determine the corresponding fragment-size distributions. Even though different types of granite and cylinder sizes were used, similar fragment distributions were produced from shots that used a similar explosive, in this case the PETN-based detonating cord, and comparable burden-to-charge diameter ratios. Significantly coarser fragmentation was produced from a blast that used dynamite as the explosive charge. Fragment velocities were calculated using photographic data from the sixth test which was shot unrestrained in a quarry and filmed with high-speed cameras.

Jan 1, 1990

By Paul Downing

A major component of an effective blasting company safety program is the self-audit. A self-audit can help reveal hazardous conditions that should be corrected and training needs that should be addressed before accidents occur, insurance claims are filed, and/or fines are levied. Such audits, when they lead to appropriate corrective action, can provide significant economic benefits for employers by reducing the costs associated with insurance claims, accidents, and injuries.

Jan 1, 2001

By Laurence Neufville

Proper risk assessment and blast design are very desirable to the execution of a blast. Not only will this ensure that it achieves its desired outcome, but the probability of complaints and litigation will be reduced. Blasting engineers rely heavily on site-specific data for analysis and input to the blast design equations, and therefore data collection is critical to this process. The traditional approach to data collection is to carry out site-specific reconnaissance by visiting the site, but the time spent doing so can be reduced if a remote sensing approached is adopted.

Jan 1, 2009

By Ronald Thomas

The scope of this paper is to examine the growth of safety in an individual and offer new goals in that development. The paper will examine the individual's natural growth and show how it parallels the individual in a safety environment. An individual's new goals for safety include more than the standard accident-free conditions. The new goal strives for a safer working environment where unsafe acts are eliminated through independent knowledge and an individual's growth of interdependency in safety related areas of concern. It will explain how this goal cannot be reached unless driven from the top down in an organization but empowered from the bottom up. Various reference or support organizations will be covered. These organizations deal with safety in mining and explosive use of manufacturing. Other support organizations exist but since this paper is "Back to Basics" only a few major groups will be covered.

Jan 1, 2001

By Don Houston

Vertical crater retreat mining (VCR) requires initiation methods that minimize debris in the borehole. The use of detonating cord and shock tube detonators eliminates debris that could interfere with subsequent loading operations and avoids the cost of using drilling equipment to clear the debris. The explosive must not be sensitive to the strength of detonating cord used, otherwise timing will be affected. “Slicing and Dicing” of product before “Air mailing” down boreholes may facilitate loading, especially in wet holes, and can result in product surrounding the detonating cord. Cord sensitivity testing confirmed that having the detonating cord surrounded by product significantly increases the likelihood of an energetic reaction. Careful formulation and testing, based on a thorough knowledge of the application and the role of ingredients in affecting performance, ensures reliable initiation and avoids cord sensitivity. The use of certain metallic nitrate salts, even in relatively small amounts, was found to significantly increase the cord sensitivity of watergel formulations. Evidence of increasing cord sensitivity includes increasing amounts of damage to product and packaging, to ejection of product from the test pipe, then cracking of the pipe, followed by deflagration then detonation of the product. Predictably, the likelihood of an energetic reaction increases with product temperature, cord strength, and borehole diameter, while it is inversely related to product density.

Jan 1, 2002

By Robert Hopler

INTRODUCTION NOT so very many years ago the farm was about the last place where one would expect to find up-to-date mechanical appliances. Steam, explosives, electricity—the factors which have made the world in general, and America in particular, what it is today— were indispensable for the railroad and the steamboat, the factory and the mine, but the farmer’s work was generally run on a comparatively small scale, and was mostly done by the muscles of men or draft animals. Today, however, the farmer as well as the manufacturer, the contractor and the miner, fully appreciate the value of labor-saving devices. Every up-to date farm, large or small, has modem machinery that tends to reduce the cost of production or to improve farm products.

Jan 1, 2011

By Frank Lucca

This study is based on a six month study performed for Lee County, Florida. The study was based on blasting for land development and how this type of blasting affects structures. The study is investigates peak particle velocities and the relationship to other environmental and manmade forces that affect structures. The study also explores the effect of geology on blast vibration. After completion in Lee County, the study was then continued in the quarry environment in Vermont and extremely tight blasting environment of New York City. Charge diameters were 127mm (5 inches) or less.

Jan 1, 2006

By He Guangyi

During rock blasting in extending deep cutting from Jiu Li Mountain to Dong Zhuang Village in Jiao Zhi Railway line, we have drilled deep hole with large scale diving drilling machine and successfully carried on controlled blasting. This has provided new experiences for rock blasting in extending existing cutting. The aim of this article is to provide an introduction to bench height, blast holes arrangement, powder charge calculation, and detonating technique during blasting.

Jan 1, 1997

By S. Nakamura, H. Taniguchi, K. Noguchi, H. Sugihara, T. Matsuzawa

It has been reported that expanded poIystyrene and ANFO prills ‘were mixed on a blasting site for controlled blasting (ISANOL). Although there seems to be few possibility of their segregation because mixing on a blasting site is done, there is a great possibility of segregation in packing, transportation and loading of the product due to the different densities of the two ingredients in Japan where mixing on a blasting site still remains inoperative. The fiee-flowing property of ANFO prills was lost with the passage of time because the Abel oil infiltrated into the expanded polystyrene and that gave the product high viscosity.

Jan 1, 2001

By Blair Jackson, Tjaart Louw

Martha Mine, owned by Newmont Mining, Australia appointed Macmahon Contractors (NZ) Ltd as the mining contractor to drill, blast, and crush and convey ore for processing, followed by construction of a tails dam facility from the waste material. The open pit is located 140km(90miles) south east of Auckland, New Zealand in the middle of the township of Waihi (the main street of the town with a population of 3,500 is 90m from the perimeter of the open pit mine). Mining must proceed at 325,000m3 (of which involves blasting approximately 11,000 holes per month, in order to ensure continued ore supply.

Jan 1, 2003

By Anders Nordqvist

LKAB operates an underground iron ore mine in Malmberget in the northern part of Sweden. Twelve different orebodies are mined today using both longitudinal and transversal sublevel caving as mining method. The town of Malmberget is located close to the mining area. The need for urban transformation, moving people and houses, is evident for many reasons. The mining methods used have inherent subsidence issues and there are also vibrations from blasting and mine induced seismic events.

Jan 1, 2018

By Bin Feng, Xiang Fang, Tao Guo, Fandong Lu

Abstract: Rough set theory (RS) can find useful information from a large number of data and generate decision rules without prior knowledge. Support vector machines (SVM) have good classification performances and good capabilities of fault-tolerance and generalization. To effectively control blasting vibration effect, prediction model of blasting vibration parameters based on rough sets and support vector machines are established. Particle swarm algorithm (PS) is used to dynamically discretize attributes. Then, according to the optimal particle calculated by the PS algorithm, the decision table is established. After eliminating less importance attributes and data, then SVM is trained and established for prediction. The model can deal with both quantitative and qualitative factors such as aperture and cast direction, and analyze their importance to peak vibration acceleration value. The improvement of prediction accuracy is verified by testing data.

Jan 1, 2014

By J. Aravena, S. Gajardo, M. Ayala, P. Salinas

Both, Teck Carmen de Andacollo (Teck CDA) and Orica, work hard in the implementation of new technologies available in the explosives industry and drilling and blasting techniques, with the objective of sustainable development of their operations, regeneration, and protection of the environment, also considering the welfare and relationship with the surrounding communities. The open-pit Carmen de Andacollo mine is located adjacent to the town of Andacollo. Therefore, both companies together have developed the implementation of different techniques and technologies to mitigate the impacts of mining operations in the community, considering an important part of this challenge to minimize the impact of their perception of blasting by reducing the level of vibrations and sound pressure (airblast), in addition to the control of dust and smoke, strengthening sustainable production in harmony with communities. The technologies and techniques that have been implemented are the installation of airblast and vibration monitoring stations stands out, whose database has records since 2011. Using the vibration database, different models were developed to predict the vibration level of blasting in its design phase, achieving a difference of 4.1% between the estimated and measured values in the last year. Two techniques stand out to minimize the ejection of material, "Hydraulic Dome" and "Dual layer blasting", the first consists of water irrigation on the surface to be blasted and the second is an unconventional blasting technique, which was awarded in 2015 for its results in the environment. Also pre-splitting engineering has been modified in a positive evolution, where through different configurations, the airblast has been reduced by 15% compared with records from 2011 to 2022. Finally, due to the impact of operational restrictions, such as days available to blast, number of holes, and powder factors, the wireless initiation technology was implemented, which allowed reducing the limitations in the loading, generating an improvement in terms of blasted materials over conventional systems. Understanding the restrictions and challenges in terms of impact on communities, the correct implementation of all these techniques is important, and in conjunction with collaborative work, it has been shown and validated that producing in a sustainable and sustainable manner is possible.

Jan 1, 2024

By David Kosnik

This paper describes the technology and methods deployed in the continuous autonomous remote monitoring of cracks in interior and exterior walls of a residence near a limestone quarry. The objective is to quantitatively compare crack response due to blast-induced ground motion to that induced by diurnal temperature changes, weather fronts, occupant activity, and other phenomena. The remote monitoring and communication technology developed to obtain and disseminate crack response data for this study may provide the means to mitigate the effect of public concerns about potential impacts of ground vibrations inherent in construction and production of raw materials; it is critical to address these concerns because subsequent litigation may result in delays and increased costs.

Jan 1, 2009

By J Silva Castro, Braden Lusk

Information management is important in all disciplines. In mining; collection and analysis of information before, during and even after mining is a keystone to performance. During mining, information is useful to optimize the resources and make appropriate decisions. Current technologies allow for collecting information in real time. Records of blasting activity at the mine are common practice in surface coal mining operations. The most common blast information recorded contains the location of the blast, scaled distance, geometry of the blast, weight of explosive used and quantity of blasted rock. Sometimes due to the proximity of protected structures, seismograph evidence of the particle velocity and airblast levels is required. However, in the majority of cases, the seismograph information is not linked to the blast information. Blast related information is recorded separately from the seismograph information and seismograms are little more than an attachment to the blast record. This fact makes simultaneous visualization and analysis of the technical details of the blast with the vibration and airblast information difficult.

Jan 1, 2012

By M Scoble, J Szymans

During the past year, the Canadian Centre for Automation and Robotics in Mining (CCARM), McGill University, Montreal, has been involved with INCO Ltd.'s Manitoba Division in investigating the extent and mechanisms of blasthole deviation. Drilling accuracy can well be regarded as perhaps the single greatest "controllable" factor influencing dilution in INCO's open sloping operations. As INCO and other underground mines seek to minimize dilution, while attempting to maximize productivity, issues of drilling accuracy become increasingly significant. It is important therefore, that means exist by which true blasthole trajectories can be determined, so that if needed, modifications to hole loading instructions or redrilling of holes can be ordered, thus avoiding poor blast results.

Jan 1, 1991