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By Jikai Rong Changai Liu

The dig instrument by blasting is a,new product we developed(See Fig. 1) It is an apparatus to dig hole at the ground. It is composed of combustor A, combustor B, charge pipe and shock head. Work characteristics of Combustor A are that combustion time is 1. 5 seconds, driving force is 725kg. Work characteristics of combustor B are that the combustion time is 1. 3 seconds, driving force is 460kg. After the combustor is ignited, the charge pipe is drived into ground immediately. Then, whole dig instrument is threw out automatically, but explosive in charge pipe is left in ground and blast in the twinkling. The diameter of vertical hole formed by blasting is 3cm to 60cm which is controlled according to engineering requirement. The maximum depth of the hole diged by using the dig instrument is 2M. It applies to blindage of single solidier in military affairs, and hole planting pole as well as sewer in civil use and so on. The two shots are charged in combustors to dig a hole. The maximum weight of shot is 490g, minimum is 130g. The whole process diging hole is completed automatically in about ten seconds.

Jan 1, 1998

By Mario Karfakis, G. Langlois

Well stimulation is the process by which any production well, whether for production (extraction), storage (injection) or deep interaction (remediation, monitoring, etc) can be made or stimulated to flow at higher levels. This stimulation is driven by active methods to increase the permeability in the near-well environment and create a larger zone of communication between a well and the reservoir it services. Well stimulation is a crucial aspect of well completion and reservoir engineering and is a subject of careful pre-drilling planning. In many modern industrial endeavors the effectiveness of well stimulation is often critical to economic viability. Because of the broad impact of well engineering on several large industries (petroleum and natural gas extraction and storage, geothermal power, groundwater monitoring, extraction and management, environmental remediation, mining and minerals extraction, etc.) changes in the state of the art in well engineering and well stimulation can affect the capabilities of very diverse and disparate industries. This paper is an effort to communicate the status and effectiveness of current practice and technology in well stimulation. The intention being that effective communication of progress can spur innovation in industries that require well stimulation but are removed from immediate communication of technological or practical improvement.

Jan 1, 2009

By Doug Wathen, Philip M. E Thomas

The City of Fort Myers needed to replace a 40-year old 42-inch storm sewer line in downtown Fort Myers with a new 54-inch line to accommodate population growth. The old line had to be kept operational while a new line was installed. the contractor spent two months using a drop ball, a hoe ram, and large rippers trying to break the three to four feet of rock that needed to be removed to accommodate the new pipe. Mechanical trenching was considered but was proven to be overly expensive. On very short notice, Ireco of Florida was asked to design and execute a blasting procedure that would allow this project to proceed. Nearby buildings were over 80 years old, three of them containing antique shops specializing in glass antiquities with attorney offices above them. High water table compounded problems with a 20-year old steel water main and clay drainage pipe 15 feet from the new sewer line. Holes had to be drilled within six inches of the edge of the existing pipe to four feet below the pipe on either side of the pipe and blasted. No interruption in the sewer line flow was to be tolerated.

Jan 1, 1996

By Midori Sakamoto, Nobuaki Sakuma, Tsuyoshi Murashita

Recently, tunnel blasting works near the residential area and existing building are increasing and environmental problems caused by vibration have become serious public concern. In order to solve these problems, blasting works have been conducted with segmented blasting and reduce advance per round. However, with these blasting, work efficiency is not obtained, and regrettably the cost and risk of accident tend to increase. We developed a new controlled tunnel blasting technique with electronic delay detonator. Electronic delay detonator can supply extremely large range of delay period which could not be achieved with conventional pyrotechnical delay detonators. We utilized advantages in initiating hole by hole over entire tunnel face at the same round. Much seismic data obtained from tunnel blasting with conventional detonator was statistically analyzed in order to find average duration time of vibration caused by a single hole initiation. Numerical simulation using sample waves from a single hole initiation was carried out in order to find an optimum delay time which can separate vibration in each hole initiation and without decreasing blast performance. Trial blasting was conducted to examine the correctness of optimum delay time obtained from numerical simulation. This blasting technique was applied to an actual tunnel construction. This tunnel is 2 lane automobile tunnel with a total length of 659 meters and internal cross section of 70 square meters. The purpose of the use of blasting technique on occasion, was the protection of fresh water reservoirs directly above the tunnel, and to keep the effect on local private houses to a minimum. The vibration level against this station was limited under 20 mm/see P.V.V. With this blasting, the tunnel construction was completed without exceeding the limited vibration level, with minimum cost and construction time.

Jan 1, 1998

By L D. Santis, L Wardrip

This paper begins with a summary of the development of the sheathed explosive charge from it's conception by the Bureau of Mines in 1981 through the evaluation of its safety, culminating in revisions to the Code of Federal Regulations (CFR), Title 30, Parts 15 and 75 which provide for its approval as a permissible explosive and safe use in underground coal mines. In 1989, Austin Powder Company decided to market a sheathed charge and proceeded to develop a commercial version which they call the Rock*Buster. The Rock*Buster was tested by the Bureau of Mines and subsequently approved as a permissible sheathed explosive unit by the Mine Safety and Health Administration (MSHA). Marketing of the Rock*Buster began in the Spring of 1990. In May 1990, the Rock*Buster was first used in an underground coal mine, Jim Walter Resources' (JWR) No. 4 Mine in Brookwood, AL. Trials with Austin's units were impressive. Representatives from MSHA, the State of Alabama, JWR, the United Mine Workers, and other local mining companies observed the charge break large boulders on the surface. Later, the charges were used underground to break large rocks from a roof fall that were obstructing ventilation. During its first week on the job, the Rock*Buster reduced the downtime experienced on JWR's longwall sections by quickly taking care of problem roof falls which halt operations.

Jan 1, 1991

By Peter Moser

The average annual consumption of raw minerals in Europe is 10 ton per person. About 50 % is produced by blasting. For a population of 450 million (including the population from the countries of the new member states) this makes 2.25 billion tons of blasted rock, 80 % being building industry aggregates and industrial minerals. In aggregate quarries 10-15 % of the rock blasted can’t be sold, as the material is too fine, i.e. smaller than 4 mm. This ‘fines problem’ is worse in the quarries of limestone and cement producers where up to 30 % of the material is useless. Thus about 450 million tons of useless rock fines are produced and put on waste dumps every year, i.e. 1 ton/person. This problem is addressed by the research project LESS FINES - “Less Fines production in aggregate and industrial minerals industry” which is funded by the European Union under the project contract G1RD-CT-2000-00438. The project consortium, formed of nine partners from 5 EU countries, works on the following two main research subjects: 1. The determination of the natural breakage behavior (NBC) of the rock mass, which is defined as the particle size distribution curve for a certain rock mass with the maximum uniformity and thus for a given maximum particle size that fragmentation curve which gives the minimum amount of unusable fine material. The comparison between the NBC and an actual blast fragmentation curve allows to quantify the fines reduction potential. 2. The adaptation of explosives properties, charging techniques and timing in order to produce only the minimum, inherently unavoidable percentage of fines. With about 15 full time working persons the project is estimated to be one of the largest blast related research activities in Europe at the time of the project period. The project is coordinated by the Department of Mining Engineering& Mineral Economics of the University of Leoben.

Jan 1, 2004

By R Yang, D B. Kay

"Blast vibration control is of vital importance for tunnel blasting in urban environments. A vibration model with multiple seed waveforms (MSW) as input for a point of interest was developed in recent years by one of its authors. The MSW blast vibration model has been applied successfully in open cut and quarry blasting situations. From the literature, it appears that there may not be any seed wave-based vibration modelling work for tunnel blasting.A project was conducted to test the MSW model for tunnel blast vibration. A series of tunnel blast rounds were fired and tri-axial vibration waveforms from the blasts were recorded with several seismographs at distances ranging from 10 to 100 metres from the blasts. Seed waveforms were collected and the charge weight scaling law for the signature hole PPV were established.The MSW model is applied to tunnel blasting and specific issues associated with tunnel blast vibration addressed, such as variable effects of confinement and screening to vibration during a blast round. The capability of the model in terms of the PPV and frequency prediction is demonstrated in the paper. The paper demonstrates that the MSW blast vibration model is a useful tool for managing tunnel blast vibration with the potential to optimise round by round design in terms of managing the vibration below the limit while maximising tunnel advance rate."

Jan 1, 2011

By M. Syafiq Isnaya, Rahma Norfaeda, Slamet Rachman Jaka

This paper is about project improvement to maximize energy distribution while ensuring beneficial blast results (reduce boulder condition). The main problem is how to manage complex lithology conditions related to detonation propagation in energy distribution control.

Feb 1, 2020

By Türker Hüdaverdi, Özge Akyildiz

"Efficiency of blast operations depends on fragmentation, overbreak, muckpile profile anddisplacement, vibration, airblast, flyrock and damage to wall or slope stability. To provide all these conditions at the optimal level, determination of rock mass properties (in-situ block size, joint spacing and orientation) is the very first step during design stage of rock blasting. Image analysis software is used not only to determine the fragmentation level of muckpile but also to characterize the bench face. In this study, an image analysis software was used to determine apparent block size of bench face and to measure blast fragmentation of muckpile. The source of errors and the vital points to be taken into consideration were explained for bench face characterization andfragmentation measurement. Since it provides much better results than previous techniques and it is not intrusive to production process, image analysis technique is considered as one of the most efficient and preferred way for fragmentation analysis. Besides these advantages, there are some weak points of image analysis software. Lighting is one of the most important factors for photographs captured for in-situ block size analysis and fragmentation analysis. Lighting determines shadow formation. In an ideal image, particles are clearly delineated by soft shadows. If shadows are too strong (dark), analysis suffers. Appropriate scale should be replaced onto blast muckpile during site measurements. The location of the scale in image affects the results of analysis. Also, the densityand orientation of discontinuities should be considered during application of image analysis technique to characterize bench faces. In this study, image analysis software was applied in thesandstone, limestone quarries of Istanbul region and an open pit boron mine. All image analysis, evaluations and results were made based on the site measurements."

Jan 1, 2017

By Orica Chile, Orica Brasil, Orica Brasil Victor Morais, Kinross Paracatu Leopoldo Muñoz, Kinross Paracatu Luis Marinho, Gubio Barsottini, Orica Brasil José Vergara, Lucas Steffen, Orica Brasil Washington Vilas

In drill and blast activities, it has been a challenge to sculpt walls accordingly to what has been designed in state-of-art mining design software. Obviously, the perfection of making neat and smooth walls – using aggressive sources of energy, like explosives – are time-and-money consumable and, sometimes, even unnecessary. But undoubtedly, it is vital to guarantee solid walls, safe operations environment, beyond to avoid ore losses and pit constraints caused by poor rock breakage on detonation. Kinross Gold Corporation owns the biggest Brazilian Gold Mine, located in Minas Gerais state. Morro do Ouro mine has reached over 30 years of operation, and due its mature age, the complex has developed its pits, becoming them deeper and surrounded by high walls.

Feb 6, 2023

By W. Reisz

Dealing with misfires can be one of the most difficult and serious issues that blasters must confront. Most of us will - at some point, have to deal with a misfire situation.

Jan 1, 2009

By Robert L. Brooks

This paper is intended for companies at all levels of the Explosive Industry and in particular, those that do not have a risk manager. It is strictly informational in nature and no reference is made, or intended towards any existing insurance company or agency.

Jan 1, 1993

By Mark William Withey

Blasting safety in surface mining is a necessary industrial goal. Proper techniques and disciplines exercised during the blasting process enhance the probability of achieving that goal.

Jan 1, 1995

By Heins Walter Wild

Detailed investigations on various configuration kinds of cut with respect to drilling-technological and blasting-technological properties as well as with respect to cost effectiveness have been carried out in Germany.

Jan 1, 1995

By C Yeung, G Fitz, R Heater, P D. Katsabanis

Explosives malfunction due to shock waves is a serious concern for successful blasting results. Malfunction can range from sympathetic detonation to desensitization and modification of firing times of conventional pyrotechnic detonators.

Jan 1, 1994

By James D. Cook, Dan McCutchen

Effective overburden casting requires the efficient use of todays explosives and initiations systems if a mine is to survive. This paper uses a major coal stripping operation as an example of the proper application of explosives and initiation system to their conditions.

Jan 1, 1994

By Stuart Pether, Cedric Goode

The Mt Morgans Minesite is located 800km North East of Perth, the Capital City of Western Australia. The surrounding region has been a significant producer of gold since the turn of the century. The mine was previously host to a township of approx 40 - 50,000 people.

Jan 1, 1996

By M Dale White

Captive insurance companies have recently been discovered by risk management experts as a risk transfer vehicle and are very much in vogue. Actually, captive insurance companies are not a new phenomenon. Centuries ago, the first insurance organizations were what we today refer to as group or association captives. Early traders banded together to share the risks of ocean shipments writing ocean cargo coverage, the oldest form of insurance.

Jan 1, 1980

By Alan R. Cameron, Alastair C. Torrance

An explosives underwater test facility has been established and commissioned in the Hunter Valley, New South Wales, Australia which allows the measurement of the actual shock and gas energies of the explosive

Jan 1, 1990

By John Brulia, Grant ODell

The AIRDEK blasting method has recently been introduced as an overbreak control blasting technique. This paper discusses the use of a modified AIRDEK blasting method for use in open-face blasting to make cap stone riprap (6-20 ton size) at the Clinton Point quarry of New York Trap Rock Corporation, Lone Star Industries.

Jan 1, 1990