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By Fred Drury

I spent 38 years in the Industry in a variety of sales, technical and management positions. I started out with Hercules, then was one of the founders of ECONEX, a large regional Distributor, and finally served with Dyno Nobel as a global Vice President, based in Oslo, Norway. When I retired in the fall of 1998, I looked forward to spending a lot less time traveling and a lot more time around home. After 4 years, I’m still traveling and still wondering how to find a few more hours in the day.

Jan 1, 2003

By Ron Gilbert

Every day, demand increases with over all population; supply must follow. People must have more food, shelter, and mobility. Raw materials must be mined. Roads, trenches and foundations support the quality of life.

Jan 1, 1996

By R W. Thomas

"This paper explores the possibilities of generating radical improvements in the drihing costs andproductivity of blastholes through the efforts of integrated teams as opposed to traditionalcustomer/vendor relationships."

Jan 1, 1996

By Denise de La Corte Bacci

The Brazilian Regulation NBR 9653 is a guide intended to evaluate mine and quarry blasting effects in urban areas. The first version, written in 1986 by the Committee of the Brazilian Associate of Technical Norms, is currently being revised. Current regulations specify a maximum PPV limit of 15 mm/s (0.59 in/s) without consideration of frequency or type of structures being protected. The present regulation is still a draft and it is not validated. Several different agencies and institutions have participated in the Committee such as the Environmental Agency from the State of São Paulo (CETESB), University of São Paulo (POLI-USP), University of Rio Grande do Sul (UFRGS), National Department of Mineral Resources (DNPM), Aggregate Industry (ANEPAC and SINDIPEDRAS), besides a number of industry representatives, explosives manufactures and independent consultants. The present regulation proposes to modify the limits of particle velocity and introduces new definitions and criteria for evaluation of vibrations, as well recommendations to address blast vibration complaints.

Jan 1, 2005

By Dale Ramsey

During Phase IV of our Landfill Mine Stabilization project at a coal burning power generating station, it was determined that a coal barrier pillar separating two abandoned areas of the deep mine had to be breached prior to expansion of the ash disposal area. The proposed plan by the landfill design engineers involved using a high pressure jet cutting tool to cut a slot to allow water flow to an existing industrial waste water treatment facility. Our plan proposed using explosives to breach the pillar from the surface reducing earth disturbance in a high quality watershed while reducing the project cost and accelerating the project time schedule. Many issues surfaced with the proposed change of using explosives. There were a number of lessons learned from this case history and is the primary basis of this paper.

Jan 1, 2003

By Thomas L. Barkley

"In early 2015 the Seed Waveform method was used to measure the Geologic response of the MesabiIron Formation to explosives energy input. This single charge wave form was then used to design acritical first blast at a newly developed Taconite mine. This initial blast had several irregular restrictions on design and performance. It had a very unusual “Frying Pan” shape, the regulatory agency required that no fly rock land in State owned waters less than 200 feet (61 m) away, there was no open face to blast to. Design criteria included the need to detonate the blast with two sinking cuts, and have the sinking cuts meet through a narrow neck between the cuts. All these had to be met using a 16 inch (406mm) diameter hole."

Jan 1, 2016

By A T. Spathis

The 11th International Symposium on Rock Fragmentation by Blasting (FRAGBLAST 11) was held in Sydney, Australia, between 24-26 August, 2015. The 93 papers, including six keynote presentations, covered exciting and practical topics in 20 sessions within 12 themes. Just fewer than 300 delegates from 27 countries attended. Four workshops were conducted on the weekend prior to the symposium, with three field visits after the symposium to Sydney region quarries, the Hunter Valley coal mining region, and the Kalgoorlie gold mining region. Delegates had the opportunity to visit the exhibition areas that showcased the latest products, software, hardware and systems in blasting technology. The keynote addresses were held in plenary sessions and set the tone for the parallel sessions that followed. They spanned the dynamics of the mining industry, the detonics of explosives, the interaction of stress waves and fracture mechanics in fragmentation, wall control blasting, and the importance of education and engineering for full process optimisation.

Jan 1, 2015

By Sandra Penttinen

To assist blasting professionals with the creation, documentation, and appropriate methodology to standardize the data collection of the pre and post blast investigation process. Penttinen Associates will present a logical non-technical presentation focusing on: Why pre-blast surveys SAVE How to prepare for pre-blast inspections What to do in preparation of pre-blast inspections The creation of an industry standard all-inclusive pre-blast document Establishing pre-blast inspection operational standards Preserving the data.

Jan 1, 2001

By Steve Dillingham

PHYSICAL BLAST DATA Pattern Description All measurements related to the description of the physical blast pattern must be made with the mind-set that it has to tell a powerful factual story enabling a future accurate reconstruction of the event. A case has never been lost because too much factual information was available to assist investigators. An accurate physical description of the pattern must be provided based on the blaster’s observations of the pattern actually loaded. The blaster must measure the pattern size, depth, face heights, etc., recording only accurate results. All too often, a blaster records simple pattern sizes and information relayed to him or her from the driller, or from a phone call into the office the night before for powder pre-load inventory purposes. If a pattern was actually measured on the job site by the blaster to be 8.5 x 9.5’, it may, in fact, originally have been ordered at 9’x9’, 8’x9’, or 9’x l0’. In a claim situation, particularly flyrock, recording a “generalization” of what was loaded could result in an interpretation of a blaster’s negligence due to “not knowing or caring” what the actual pattern was, and not loading appropriately for conditions. It is important to remember that other documentation exists such as a drill log from a contract driller or mine records that may provide a different interpretation of the loaded pattern.

Jan 1, 2002

By C. Braun, C. Kennedy, P. Katsabanis

A series of small scale tests, simulating multi-hole blasts have been performed to establish the effect of delays on blast fragmentation. The blasts were performed in high quality granodiorite blocks, which were cut from stone prepared by dimensional stone quarry operations. The pattern used was equilateral triangular, with a distance of 10.2cm between boreholes, which had a diameter of 11mm, were loaded with detonating cord and the coupling medium was water. The delays used were achieved using different lengths of detonating cord for the cases of delays between 0 and 100 microseconds between holes and a sequential blasting machine firing seismic detonators for larger delays up to 4ms. All fragments were collected and screened. The experiments showed that the coarsest fragmentation was achieved with simultaneous initiation of all charges. Fragmentation became finer with delay time between holes up to 1ms between holes. The results show that in moderate to competent rock, similar to the granodiorite of the experiments, fragmentation optimization requires delays of few milliseconds per meter of burden. In view of the findings, which agree with previous published work, the current trend of selecting fast firing times for fragmentation optimization is questioned.

Jan 1, 2006

By Dr. Calvin J. Konya, Anthony Konya

Blast violence has always been a criteria that has been analyzed without a quantitative approach relying on opinions of those viewing the blast and oftentimes does not transfer between open-pit mines, quarries, and construction projects. Added to this confusion is that on many regulate projects, such as U.S. Army Corp of Engineers construction projects, the definition of "flyrock" or violence can vary, and contractors must be able to meet this requirement. This project analyzed hundreds of blasts from various construction projects to develop a new metric to determine blast violence - the Violence Factor.

Feb 1, 2020

By Dr. Calvin J. Konya, Anthony Konya

Blast violence has always been a criteria that has been analyzed without a quantitative approach relying on opinions of those viewing the blast and oftentimes does not transfer between open-pit mines, quarries, and construction projects. Added to this confusion is that on many regulate projects, such as U.S. Army Corp of Engineers construction projects, the definition of "flyrock" or violence can vary, and contractors must be able to meet this requirement. This project analyzed hundreds of blasts from various construction projects to develop a new metric to determine blast violence - the Violence Factor. If a blast is fired using 1.25" (32 mm) diameter product and a 10-foot (3 m) bench, vertical uplift of 60 feet (18.3 m) would be considered extreme and violent by any professional in the industry. However, a 100-foot-high (30.5 m) bench using 12" (305 mm) bulk product, having a vertical displacement of 60 feet(18.3 m)might be considered typical or non-worrisome. This is where violence factor is beneficial as itprovides a system of scaling the violence of a blast based on the bench height to give manager a keyperformance indicator (KPI) which is easy to monitor and can provide a large amount of information onsite-specific design variables for their performance on blasting and the end-results of the blast. The Violence Factor of a blast is an integer which is scaled to determine how high vertical uplift of a blast is compared to the bench height. This project analyzed numerous blasts to determine what blast design variables contribute to violence. This violence has also been shown to occur when a non-optimal breakage mechanism, cratering, occurs and the design criteria that lead to this cratering. Finally, this paper will present typical results of various levels of violence including backbreak, fragmentation, and muckpile configuration.

By Raden Haris Handayana, Jerri Mapanta, Eri Barlian, Milia Putri, Nasfryzal Carlo, Jihan Lubis

Waste oil is a growing problem throughout industries where environmentally responsible disposal ways are usually costly. There are many industries have developed process to reuse of waste oil as a source of energy on their own premises. Hanwha Mining Services Indonesia is one of blasting service that manufacturing explosive using waste oil. The usage of 60 % waste oil content in fuel solution already developed applied since 2020 at Petrosea-Kideco Site and will be increase until 100 % in 2022. The purpose of this research is to analyze the increasing of waste oil usage from 60 % to 100 % content at Petrosea Pit without reducing the emulsion quality and performance, and surely eliminate the fuel cost and reducing waste oil processing cost. Some trial conducted to determine the effect and quality of using 100 % waste oil content on emulsion at production blast. The method use to know the quality of 100% waste oil of emulsion is by direct application on bench blast. Using Microtrap VoD recorder, explosive energy will be recorded into m/s dimension, microtrap recorder the speed of explosive detonation in line with the speed of burning wire in the blast holes. The summarized of this research present that the using of 100 % waste oil content on emulsion can be applied on bench operation with the result of Velocity of Detonation (VoD) data is 4,559 mm/s, the mean of fragmentation size is in range 65.31 to 225.62 mm, the average of digging time on 1st layer is in range 10.2 to 11.6 s and on 2nd layer is in range 8.9 to 9.5 s, and the productivity still achieve on target. The result of all parameter quality still in the standard range of Hanwha and Petrosea.

Feb 6, 2023

By Norman Paley

A blasting project was undertaken at the Teck Alaska Red Dog Mine to determine the extent that Semi-Autogenous Grinding (SAG) mill throughput could be increased by using electronic detonators. The Julius Kruttschnitt Mineral Research Centre (JKMRC) blast fragmentation, jaw crusher, and SAG mill breakage models were used to relate changes in the blast fragmentation measured with the SPLIT image analysis system to the SAG mill performance. For optimum performance a SAG mill requires a particular size distribution; a number of large rocks to facilitate breakage by impact, as few as possible middle size rocks that become critical size, and the maximum fines which will pass quickly through an open-circuit mill. Physical constraints of drill and charging equipment size limit the extent that pattern geometry can be changed, and the powder factor increased, to maximize fines. However, a growing number of studies have shown that the use of electronic detonators can lead to increased fragmentation and greater muckpile uniformity, providing an alternate means of increasing primary breakage by blasting. Unfortunately results in the literature rarely quantified the changes to the fragmentation distribution. The measured gyratory crusher fragmentation of 2,750,000t of ore was used to compare stockpiles constructed from shots using pyrotechnic detonators to those using Orica i-kon electronic detonators. In the first stage of the study, stockpiles shot using 25 ms inter-hole timing with pyrotechnic detonators were compared to stockpiles shot using the same inter-hole timing with electronic detonators. In the second stage of the study, stockpiles shot using 17 ms inter-hole timing with pyrotechnic detonators were compared to stockpiles shot using 8 ms inter-hole timing with electronic detonators. When electronic detonators were used with the inter-hole timing kept constant, fragmentation uniformity was slightly increased, but mean fragment size increased by 20%. When electronic detonators were used with faster inter-hole timing, fragmentation uniformity was slightly reduced, but mean fragment size decreased by 30%. Modeling was used to determine the SAG mill throughput which could be expected from this change in fragmentation to determine the pairs of pyrotechnic and electronic blast pattern geometries that would provide similar throughput. The economic benefit from the electronic detonator shots was calculated to assist in determining the optimum blast designs for their use.

Jan 1, 2010

By John Montgomery

This paper discusses the major changes to the Commissioners Rules and Regulations, Chapter 120-3-10 “Rules and Regulations for Explosives and Blasting Agents”; how the changes came about, and a summary of the status of the blasting industry in Georgia.

Jan 1, 2003

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan

In the bench blasting, the realisation of an economic, and safe blasting is only possible with a reliable blasting design on condition that considering all sequential activities such as drillingblasting, excavation-loading, haulage, crushing (especially primer crushing). Here what we mean with a good, and reliable design is that ensures an almost displaced, adequately swelled muckpile with desired fragmentation degree for the loaders effectivity, and succesive usage. Meanwhile it must also has no environmental problems such as ground vibration, air blast, and rock flyings, or at least these matters have to be minimised. Two main parameters which have generally being questioned to achieve a safe and economic design on any rock conditions, are specific charge, and burden. In the condition of determining these elements, the other blasting parameters could be calculated according to them, and the blasting design could be completed. Within the scope of this study, it was aimed to determine the optimal blasting conditions of gypsum which is major rock unit of overburden at Sivas Celestine open pit mine. First of all, the engineering (mass, and material) and digging difficulty classifications of gypsum were done according to the current classification systems by using the results of field and laboratory studies. Then the blasting system which was being used on all rock units, was considered, and the necessary data were obtained. After previewing the site properties, predesigns were done, and applied by adopting Langefors design model. The necessary adjustments were done before, during, and after the shots, and the applications were observed. In order to determine, and record the data from each shots properly, a practical form was developed, and all data were transfered to these forms which give information about the blasting results such as muckpile displacement, and height, average particle size, back break, and rock fly existence, number of boulders etc. The blasting parameters such as burden, hole diameter, hole inclination, the amount and position of primers, bench height, delay sequence, and blasting geometry were considered for the iteration of each shots. During the applications, ANFO, gelatine dynamite, and electric delay detonators were used as explosives.

Jan 1, 2004

By Mick Lownds, Ruilin Yang

The potential advantages of electronic detonators with accurate timing have been increasingly recognized by the blasting community. However, in comparative blasts the results with pyrotechnic timing are sometimes comparable to those from electronic timing. Statistical variation in blast results is a plausible cause of these observations.

Jan 1, 2011

By Michelle Crull, Susan Hamilton

Explosives safety requirements in the United States began in 1909 when the American Railroad Institute questioned explosives manufacturers regarding distances necessary to protect employees and property. In response to this inquiry, a group of explosives manufacturers collaborated to study over 200 explosive accidents. This study resulted in the 1914 American Table of Distance (ATD) published by the Institute of Makers of Explosives (IME). The 1914 ATD provided suggested separations between explosives and inhabited buildings, public highways, and public railways.

Jan 1, 2010

By Raden Haris Handayana, Jihan Farhan Lubis, Milia Putri, Tengku Deli Hamonangan Hasibuan, Sani Salahudin

An environmental issue that must be controlled from coal overburden blasting near the structure is ground vibration. Damaging ground vibration is the effect exerted from residual energy from blasting that does not work to fracture the rocks. Sebuku Tanjung Coal is a coal mining that operates T3 Pit adjacent to the High Voltage Tower. This structure is included in the Class 5 building with a maximum Peak Particle Velocity (PPV) of 40 mm/s. The shortest distance from the blasting location to the structure is 105 m. The initiation system used is electronic detonators combinate with emulsion as an explosives type. In Indonesia, the government regulated vibration limitation on SNI 7571:2010. The blast outcomes targeted are PPV below 40 mm/s, fragmentation size <80 cm for Excavator Komatsu PC-2000, and digging time <12 seconds. In this paper, the blast design was engineered by conducting Signature Hole Analysis for optimizing delay timing configuration and Scale Distance regression analysis to determine optimum charge weight per delay at the blast site. PPV results from 30 blastings achieved 100% below 40 mm/s with the range of about 1.773-30.250 mm/s. The deviation between PPV prediction to PPV actual is less than ±18% which provides the blasting with electronic detonator resulting in good PPV prediction for controlling vibration. The average fragmentation size (D80) is 55.81 cm in the 1st layer and 54.81 cm in the 2nd layer. The average digging time is 10.30 seconds in the 1st layer and 10.12 seconds in the 2nd layer.

Feb 6, 2023

By Rob Lederer, Chris Batten

Traditionally coal model digital terrain models (DTM) are created from lithological information obtained from broad scale exploration holes. The grid layout and distance between holes means that models do not commonly display local variations of seam dip, faulting and shearing. Due to this, issues can often arise when designing the loading of blast patterns based on potential variances between model and actual coal seam locations. Many sites will often attempt to create more accurate models through the collection of data from coal edge pickups on highwalls and in blast faces, along with information recorded by drillers (touch coal holes) from both production and presplit holes for both the current and previous blasts.

Jan 1, 2012