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By James R. Houston, Wendel Clay Chaffin, John Loviza

During the spring and summer of 1993 the largest pipeline in Tennessee was installed as part of the upgrading of Nashville's sewage needs through the year 2035. This new 3.3 million dollar outfall project is able to carry 330 million gallons of treated sewage water daily. Special projects required special equipment as this project was safely and quickly installed.

Jan 1, 1995

By Charles B. Ingram, Neil E. Gehrig

The development of water gel explosive products has been the single most important development in explosive research and development since the invention of nitroglycerine and dyne-mite many years ago. m e Explosives Department of Gulf Oil Chemicals Company has been engaged in the research, development, manufacturing an marketing of slurry explosives and blasting materials for over twenty years. Explosive research and development is being carried out at the Jayhawk Technical Laboratory and the Underwater Testing Facility near Pittsburg, Kansas. There are fourteen manufacturing facilities geographically located around the country to serve the mining, quarrying, and construction industries with a complete line of explosives, blasting agents, and accessories. This paper discusses the Gulf slurry products, their properties, and uses.

Jan 1, 1977

By William. J. Birch, Catherine. E. Johnson, Robert Farnfield

Rocks and other materials can be characterized by their elastic properties. However, seismic velocities represent a more practical set of physical properties for seismic methods. Seismic velocities define the speed at which various elastic deformations propagate through different rock types. Seismic velocities for a given material can be expressed explicitly in terms of their elastic properties. It is widely accepted that the peak particle velocity and associated frequency of ground motion are important parameters for determining a safety criterion to minimise the potential for both damage to structures as well as nuisance to people. Whilst the key considerations are the blast design parameters, the seismic velocity is important as particle velocity is dependent in part on the powder factor [blasting ratio] which in turn is found to be dependent on the seismic velocity.

Feb 6, 2023

By Bilegt Batbold, Bayu Saputra, Chris Batten

The ability to fire multiple blasts simultaneously can provide significant benefits to any open pit mining operation. Reduced blast-related downtime by reducing blast events can increase equipment utilization and maximize material movement. Significant sequencing benefits can also be delivered, associated with reduced equipment relocation. This paper describes the work completed in partnership between Orica and Oyu Tolgoi to successfully demonstrate that combined production-trim and midsplit blasting could be implemented successfully while successfully managing the risk of increased damage to the final walls. The paper details the methodology used to assess key performance measures linked to final wall damage and compares the performance between the following blasting methods. • Free face trim blasting vs. combined production-trim blasting • Presplit blasting vs. midsplit blasting. The results of the initial trial blasts are presented, along with the method agreed by the key site stakeholders for ongoing application. The method used to keep the risk of final wall damage to an acceptable level is explained, along with the benefits delivered to Oyu Tolgoi operations associated with the initial 12 months of application.

Jan 21, 2025

By Gennaro Di Lauro, Laura Meraviglia, Demostenes Efstratiadis, Danilo Coppe

This paper presentation regards the European Union’s project “I.C.E.A. - Identification Colors of Explosives and Blasting Accessories (Agreement number – HOME/2010/ISEC/AG/071 – 30 – CE – 0447240/00-11), submitted under the call for proposal “ISEC 2010 ACTION GRANT” of the “Prevention and Fight against Crime” Program of European Commission. The main objective of the project is to simplify counter-terrorism security measures and the procedures for visual identification of blasting devices.

Jan 1, 2015

By Roberto Folcht

The obligations of the European Directive 96/82/EC on the control of major accident hazards, the so-called Seveso II Directive, became mandatory within the E u ropean Member States February 3, 1999. Explosive products have been included within the Seveso II Directive, in the categories of substances capable of generating a major accident. In addition to taking “all measures necessary to prevent major accidents,” explosive manufacturers are also obliged “to limit their consequences for man and the environment.” However, for explosives in particular, no pro c e d u res, nor specific re f e rence values for damage calculation, are given either in the Directive or in the corresponding Italian Legislation, “Ministry of the Environment decree of 20 Oct. 1998.” This article presents a simplified but scientifically rigorous approach for the first approximation calculation of the effects on the surrounding area following an accidental explosion. As an example of the method of calculation, the damage areas in a hypothetical explosives manufacturing facility, as shown in F i g u re 1, will be anal y z e d . The method proposed in this article can also be used for the analysis of explosions of gas in tanks or pipelines,

Jan 1, 2004

By Antonio S. Aldana Selders

With special designed explosive and a system to lower down a heavy load of Explosives through 8" pipe results are achieved, the stimulation of sulphur production takes place. Well # 18-1063 at 515 meters below ground is loaded with 802 units of explosives with total weight of 1820 kilos to fill up the column of 93 meters of limestone & sulphur strata.

Jan 1, 1995

By Kristen Dunlap

There are several thousand remote stream crossing structures in the Tongass National Forest in need of removal. In 2007 thirty-three collapsing log bridges, log culverts, and metal culverts no longer in use were removed with explosives. Species of salmon, trout, char, and sculpin are present in the project area. Blasting overpressures may injure or kill fish in streams and ground vibrations can damage salmonid embryos in streambeds. Regulatory agencies offer guidelines with limits for blasting induced overpressures and vibrations. However, there has been no quantification of blast overpressures in shallow streams. Methods used to predict lethal levels for various blasting applications have not been completely validated. This research provides guidance for analyzing ground vibrations and water overpressures during blasting activities in or around fish streams.

Jan 1, 2009

By Judy Konya Bowles, Calvin J. Konya

Blast vibration and air blast are commonly blamed for damages to residential as well as commercial structures. Mining and construction companies are often required to spend monies in court defending themselves even when vibration and air blast levels have been monitored by seismographs and are extremely low.

Jan 1, 1992

By Lon Santis, Dale Ramsey

The use of aircraft to support blasting operations in mines, quarries and construction sites goes back to the early days of aviation. Invaluable at times, aircraft use has been limited by cost, the unpredictability of weather impacts and other factors. Recently several technologies have matured to open up a new way to acquire aerial data with unmanned aircraft systems (UAS), commonly called drones. Equally important, the U.S. Federal Aviation Administration has recently implemented an exemption process and rulemaking to implement the commercial use of UAS into the United States’ National Airspace. The skies are opening for many applications of UAS. The most notable may be photogrammetry, which is the science of making measurements from photographs, especially for determining the exact positions of surface points.

Jan 1, 2016

By Larry Mirabelli, David Lilly

In 1777, the French naturalist, Georges Louis Leclerc, Compte de Buffon developed a statistical technique to estimate the width between two parallel lines by randomly throwing a needle at the two lines and counting the number of times the needle intersected one of the two lines. By knowing the length of the needle, the distance between the parallel lines could be estimated. This analysis was named the “Buffon’s Needle Problem”.

Jan 1, 2008

By Kirlk Yeager

"Ammonium nitrate (AN) is commonly mixed with a wide variety of additives to produce specialty formulations. Two additives commonly utilized are sodium nitrate (SN) and sodium nitrite (SNi). Application of the nitrite is primarily limited to gassing of emulsions. The nitrate, however, is incorporated in a wide variety of formulations. The effect of both these materials on the thermal stability of AN was examined. Experiments initially utilized lab-scale testing methods (sub-milligram sample size), such as differential scanning calorimetry (DSC), with scale-up to cook-off analyses (16 g) eventually applied. Labscale testing indicated that the presence of SN and SNi (both at 5 wt%) produced no harmful effects on the thermal stability of AN. The cook-off results did not agree with those from the lab-scale analyses, with both SN and SNi creating tremendous thermal destabilization of AN. These effects were seen at additive levels as low as 0.1 wt%. When SNi was employed as the additive, cook-offs became violent enough to create explosions in the testing apparatus. Although SN did not create as spectacular a destabilization, it did lower cook-off temperatures to approximately the same level as SNi. The dangerous situation created by SN andSNi seemed to be limited to cook-offs conducted in sealed vessels. If the SN/AN or SNi/AN formulations were allowed to cook-off in vented vessels, the thermal destabilization of AN did not occur. These results seemed to indicate that even “trace” amounts of what might ordinarily be viewed as benign additives could create significant destabilization of AN-based explosives under proper circumstances. Conditions created by blocked pumps, or deep boreholes could well overlap those produced in sealed cook-off vessels. In addition to showing the hazards potentially created by “benign” additives, the study also stressed that experiments designed to evaluate thermal hazards must include duplication of field variables to the fullest extent possible. "

Jan 1, 1999

By Vincent Thorne

On January 2, 1992, the R. Zoppo Company of Stoughton, Massachusetts started drilling and blasting operations on U.S. Army Corps of Engineers Project Number: DACW33-91-B-0072 to widen and deepen the Portsmouth Harbor and Piscataqua River Navigation Channel.

Jan 1, 1993

A simple and cost effective technique to increase fragmentation and burden velocities without making major modification to the overall blast design is with ALTERNATE VELOCITY LOADING OR BOOSTERING OF ANFO. The technique requires the placement of a cartridge or slug of explosive, having higher density and detonation velocity than ANFO, every few feet in an ANFO column. The greater the difference in density and detonation velocity of the Alternate Velocity Load to ANFO, the more pronounced are the results. Emulsions were selected as the Alternate Velocity test explosives because they detonate closer to ideal conditions than most other commercial explosives.

Jan 1, 1989

By Reynold N. Hoover

The bombing of the Murrah Federal Building in Oklahoma City, Oklahoma, on April 19, 1995, has once again renewed public debate surrounding the availability and use of explosives in the United States. In the past, Congressional review of explosives regulation has generally followed tragic events such as the bombing of Pan American World Airways Flight 103 over Lockerbie, Scotland on December 21, 1988; the February 26, 1993, bombing of the World Trade Center in New York City; and the delivery of six package bombs to members of one family in several western New York communities, killing five people, on December 23, 1993.

Jan 1, 1996

By Alan: Moore Richards

Effective control of airblast requires that significant factors be identified and satisfied by blast design and careful implementation. Significant factors include charge mass, distance, face height and orientation, burden, spacing, and initiation sequence, stemming height and type, topographical shielding, and meteorological conditions. This paper utilizes case histories of blasting in Australian open pit mines to demonstrate techniques that have been used to control airblast to applicable limits.

Jan 1, 2006

By Julia Creasey, Natalie Hodgson, Claire Ward, Craig Davies, Helen Sarginson

"Emulsion explosive producers are attempting to lower the cost of emulsion production by using lowquality ammonium nitrate in emulsion formulations. Low quality ammonium nitrate contains additivessuch as anti-caking agents and crystal modifiers which contaminate the emulsions causing instability. This presents a need for an effective emulsifier that will maintain emulsion stability under thesechallenging conditions."

Jan 1, 2017

By Rachel L. Bauer, Catherine E. Johnson

Explosive demolition involves first, the use of cutting charges to sever a column and second, kicker charges to move it out of alignment. Dynamite is the traditional explosive used in kicker charges as it is inexpensive, easy to initiate, and has a consistent track record of use. Dynamite, however, has health concerns in handling, fragmentation concerns from direct contact on the beam, and availability concerns due to being manufactured at only one location in the continental United States. Recently, water-cased kicker charges have been used in industry, and research has shown that a reduced dynamite mass is possible due to the added confinement, for energetic performance, and the incompressible fluid, which aids in the transfer of explosive energy into beam movement. This research will compare two different explosives, an emulsion (DYNO AP), and binary (HELIX), to dynamite for use in kicker charges, both with and without water-casing. Emulsion is commonly used in rock blasting to create a large push or throw due to its high gas volume production which could translate to kicker charge movement. HELIX is a binary explosive commonly used by the military in breaching charges with water backing. Experimental tests placed kicker charges at the base of a hanging steel column, modifying the ballistic mortar test used to determine explosive power. The study shows that water-casing effectively reduces air overpressure and enhances explosive performance. Among the tested explosives, HELIX showed the most substantial improvements with a 1.8 dB reduction in air overpressure and a 3.2 m/s (10.5 ft/s) increase in column velocity when water-cased. Dynamite and emulsion also benefited from water casing, with decreases in air overpressure (1.1 and 0.7 dB respectively) and increases in column velocity (1.1 and 0.7 m/s (3.6 and 2.3 ft/s) respectively). This research also shows that emulsion is a viable replacement for dynamite in demolition projects, performing similarly in both traditional use and water-cased charges.

Jan 21, 2025

By S A. Steyn, P Terrett

Air decking has become a widely practised method internationally for modifying fragmentation results and providing cost savings from reduced explosive consumption. Duvha has been applying air deck technology to overburden and midburden blasting for a few years. A thorough evaluation of air decking at Duvha has been made by instrumenting a number of blasts and analysing costs from direct savings in reduced explosives costs to savings in improved dragline productivity.

Jan 1, 1995

By Steven Townend, Don Wadden

In today's global economy the need to stay competitive is essential for commercial survival and growth. To this end Inco is committed to continuous improvement in its operations. Various aspects of the mining process have been examined to find ways of improvement.

Jan 1, 1994