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By Frank Hirthammer

Productivity, customer relations, and effectiveness of work depend to an ever-increasing extent on a functioning logistics system tailored to the needs of the user. Of course, it is not possible to cover and explain all aspects of the logistical requirements of even a small part of an industry, in a single article. The article speaks specifically about the particularities and differences in the logistical requirements in the explosives sector. Starting with questions of safety, handling and quality up to the legal basis, there are special requirements regarding the logistics in the explosives sector. The results of innovative logistics solutions are presented using three examples from daily work practice.

Jan 1, 2019

By Tom Treleaven, Andrew Williams

Several contracts were let in Greenwich, Connecticut, for the installation of a sanitary sewer. The majority of the excavation was in rock and involved numerous challenges due to the following conditions:

Jan 1, 2003

By Henry S. McDevitt

External Shock Mitigation (ESM) is being studied as a possible means of retrofitting existing buried structures to provide additional protection from ground shock. As part of this study, two tests were conducted on four ESM models and a control structure. The test articles were placed at a carrnon distance and subjected to the ground motions created by a buried explosive charge consisting of 2,ODO pounds of nitranethane (NM). Adequate instrumentation data were obtained to assess the response of the four ESM models. The assessment relied heavily on direct comparison of horizontal motions measured in the models, with similar measurements in the control structure. From the tests, it was observed that peak accelerations were reduced by a factor of 5 by the ESM. However, the particle velocities and displacements were not significantly affected by theEIS.

Jan 1, 1997

By John Vynne

Too often, a mine’s operations, including drilling, blasting, loading, hauling, crushing, processing, etc., are considered independent steps, rather then a continuous process. In fact, these are interdependent operations with each step in the process having an impact on subsequent operations. If the effectiveness of the drilling and blasting operations can be improved, they will impact the entire mining process. Some of the resulting improvements include: level benches on grade; fragmentation and diggability with the result being reduced loading times; haul cycles improvements; and the crushing and milling operations will be more efficient and less energy consumed. Thunderbird refers to this as “Drill to Mill” information cycle or process. This paper focuses on two of the technological enhancements Thunderbird has added to its drill monitors that allow the mines to impact the “Drill to Mill” concept. These enhancements are: incorporating global positioning satellites into drill monitors; and radio off-loading of data. Thunderbird is part of the Integrated Mining Systems (IMS) alliance. IMS offers the mining industry the most comprehensive line of monitoring and navigation products available today for mobile mine equipment. In addition to Thunderbird’s drill monitors and GPS systems, the product line includes: Fleet Management Systems for trucks and loaders; dragline and shovel monitors; GPS based navigation systems for shovels, dozers and other mobile equipment; and surveying systems. IMS uses common communication systems, operating systems, and hardware components in order to provide a truly Integrated Mining System.

Jan 1, 2000

By P D. Katsabanis

This chapter describes the principles for the derivation of the equations for a detonation wave. The importance of the equation of state for the detonation products is demonstrated and commonly used equations of state are discussed. Furthermore a brief introduction to the TIGER code is presented.

Jan 1, 1991

By Mick Fritz, Tom Treleaven

The success of any blast is dependent on the accuracy of the blast design and field controls placed at the shot location. The procedure by which the data is collected and analyzed is paramount to accomplishing the anticipated blast results. lf the geometry of the blast is not measured correctly, then the results will not meet expectations. Measuring the geometry and compensating for bole hole deviations is crucial not only to the lnitlal blast but also for any consecutive blasts. Excessive bore hole deviation can cancel any new technology in use. However the instruments and skills required solving this Issue are readily available.

Jan 1, 1998

By William G. Szymczak

A set of experiments were conducted at the Aberdeen Proving Grounds [1] in which explosive charges were buried in saturated sand beneath a suspended rigid platform. The goal of these experiments was to measure the dependence of the impulse transmitted to the platform on the standoff distance and the charge burial depth. Simulations of these experiments were performed using the BUB2D axi-symmetric code using a frictional-cohesive visco-plastic model to describe the response of the saturated sand. This code solves a constrained set of conservation laws in which the liquid region (in this case saturated sand) is assumed incompressible. The explosion is initialized as a high pressure gas bubble (void) within the fluid. Comparisons of the simulations to the experiments are presented together with a study of the physical phenomenology associated with the loading process. In particular, it is shown that the force imparted to the platform is a combination of the impact of the sand on top of the explosion gas bubble and the pressure of the bubble as it expands before venting into the atmosphere. Under certain conditions, when the platform standoff is sufficiently small and the platform is sufficiently large, the bubble can over-expand before venting and pull the platform downward. This phenomenon was studied further through carefully measured and photographed small-scale experiments performed at the University of Maryland [2]. The small-scale experiments provide additional important validation benchmarks for our model.

Jan 1, 2005

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 John R. Holliday, William Marcum

Apogee Coal Company, DBA Arch of West Virginia, faced the challenge of drilling and blasting over one million cubic yards of high temperature overburden at its Ruffner surface operation near Logan, West Virginia. The overburden was removed above the Upper Five Block seam that was previously deep mined, abandoned, and later engulfed by fire. Borehole temperatures were measured above 700” F.

Jan 1, 1996

By Tom Palangio, Ralph M. Olmstead

Video inspection of boreholes with cameras developed specifically for the mining industry is now possible. These designs are reliable, cost effective, and have the flexibility to be used in other applications.

Jan 1, 1998

By Robert B. Hopler

The history of the first twenty years of the high explosives industry in the United States begins as an illustration of the free enterprise system at its best and ends with the industry virtually taken over by a single company: a company which strongly opposed the new explosive material at the beginning of the period. In the world of the late Twentieth Century we could almost compare this history to the opposition of the mainframe computer manufacturers to the introduction of the personal computer, and their later entry into, and attempted dominance of, that market. With computers in the twentieth century the attempt to dominate the market has not been particularly successful: with dynamite in the nineteenth century it was.

Jan 1, 1994

By Michael D. McGill, Jeff Freadrich

There are many factors which affect the productivity of a front end loader. One of the most obvious is the characteristics of the material being mined. Characteristics such as size distribution, swell factor or heave, and material hardness / abrasiveness will all effect the efficiency of the mucking cycle. The focus of this paper is to look specifically at the size distribution of blasted material, and quantify the effects on loader productivity.

Jan 1, 1994

By Robert Hopler

A blast caused the destruction of a bridge and loaded freight train and the death of three men, near Chattanooga, Tenn., on May 16, 1907. The blast and its disastrous effect has been described by Mr. Hunter McDonald, M. Am. Soc. C. E., in a paper read before the Engineering Association of the South and reprinted in the Proceedings of the Association for April-June, 1907. The excessive damage was so largely due to coincidence and wreckage of the bridge and train so complete that the incident is worthy of notice.

Jan 1, 2008

By P D. Katsabanis

According to Persson(1) steady state detonation along a cylindrical charge can be regarded as a self propagating process in which the axial compressive effect of the shock front discontinuity changes the state of the explosive so that exothermic reaction sets in with the requisite velocity.

Jan 1, 1990

By Dale Preece, Steven Sobolik, Richard Jensen

Recent events demonstrate that civil and government facilities and structures face an ever-increasing need to be designed for protection against malevolent explosions. Modification of existing public structures and especially design of new ones increasingly includes provisions for explosive protection. ISEE members endorse and promote responsible application of explosives to benefit mankind and deplore any other use. However, our knowledge of explosive behavior and our ability to predict the results of explosive events puts us in a unique position to give guidance to designers of civil and public structures. Recent advances in computational methods have resulted in new computer codes with ALE (arbitrary lagrangian eulerian) simulation capabilities. Historically, lagrangian computational methods have been used for modeling solids because the mesh or discretization moves with the material. Rock breakage resulting from explosively induced shock-waves has been successfully modeled with lagrangian codes. Explosive detonation has traditionally been modeled with eulerian techniques. Eulerian methods have been used to model gases and fluids, tracking the material as it moves through the computational grid. ALE computational technology couples the two methods together in a manner never before possible. An ALE simulation can accurately treat the explosive detonation, interaction of explosive gases with air, and the impact of explosive event on nearby solid structures. ALEGRA (Budge et al. 1997 a & b) is an ALE code developed at Sandia National Laboratories. ALEGRA simulations accurately predict the explosively induced impulse on the structure to be protected. It has been applied to the analysis and design of blastwalls to protect structures and people from explosive events. The impulse calculated can be used by structural engineers to design a blastwall. ALEGRA has also been applied to predict the effect of a blastwall on explosion overpressure some distance behind the blastwall to assess the effect on people present during the event.

Jan 1, 2000

By Simon St. John Tose

We have had a long history in supporting the development of training material to ensure “safe” blasting. This has been provided as both significant technical guidance to the industry and input into the development of the new industry surface rockbreakers or shotfirers qualification in South Africa (RSA). The learning material supplied to the industry is based on both a classroom knowledge component and an assessment on the practical application of the learning by the trainee blaster on the job under the supervision of the appointed blaster. This training includes all blasting applications which can often extend beyond the “normal” mining environment of open pits, underground and quarries into civil applications such as trenches, blasting close to private buildings, public roads, pipelines, power lines, swimming pools and the removal of concrete structures and building demolitions etc.

Jan 1, 2013

By Shazad Hosein, William Birch, Douglas A. Anderson

This paper will present the results of tests of a new method for assessing explosive performance using wavelet transform analysis of standard blast seismograms. The theoretical background of the method was presented at an earlier ISEE conference.

Jan 1, 2015

The common approach of designing blasts on a trial and error basis is quickly coming to an end. When utilizing the full scale blast environment, trial and error can quickly become cost prohibitive and leaves much to be desired in terms of true blast diagnostics. In these situations testing is usually only continued until a perceived improvement is achieved and when the gross undesirables in blast results are removed. This does does not preclude, however, that further improvements of up to 100% or more can not be obtained.

Jan 1, 1991

By Robert B. Hopler

First, a definition: “an explosive is called a permissible explosive when it is similar in all respects to the sample that passed certain tests by the national Bureau of Mines, and when it is used in accordance with the conditions prescribed by that bureau. * This was the definition as stated in Miners’ Circular No. 2,” published by the United States Bureau of Mines in 1911, and it is still applicable today. Of course there have been changes over the years, with the name “MSHA Permitted Explosive” now the legal terminology since January 1989, but the old 1911 circular still tells us what the material is. Note that the definition doesn’t even specifically state “coal mining.” A permissible can be required in guy underground operation that is deemed to have a gas or dust hazard, although in 1911 it was certainly meant to refer only to coal.

Jan 1, 1995

By Robert Hopler

True there is a certain proportion of nitro-glycerin in dynamite cartridges, but the dangerous explosive is scientifically compounded with wood pulp and some other ingredients in such a way that it can be absolutely depended upon not to explode accidentally if our simple and plain instructions for its use are complied with.

Jan 1, 2012