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By Richard J. Mainiero

Traditional techniques for the experimental determination of toxic fumes produced by the detonation of high explosives are not applicable to blasting agents. To detonate properly, blasting agents require confinement, a significant booster, charge diameters of 3 inches (7.5 cm) or greater, and charge lengths greater than two times the charge diameter. Without these conditions, blasting agents will not detonate at full order, leading to a misrepresentation of the gaseous products.

Jan 1, 1997

By Paul Worsey, Barbara Robertson

In June 2007, Missouri Science & Technology (formally UMR) successfully held its 5th and 6th Explosives Summer Camps. The camps, which include substantial industry participation, have been an outstanding success with both the students and their parents. They have also spawned a large amount of local, state and national media attention, including NPR and an article in the New York Times on the 3rd of July 2007.

Jan 1, 2008

By Tom Short

The contract to drive twin 4,100 foot (1250.5m) long tunnels under the existing Cumberland Gap highway was awarded to a Joint Venture of S.A. Healy of Chicago, Illinois and Lodigiani USA of Fairfax, Virginia in January of 1991 under a $51.8 million bid. Due to very complex geological conditions, there were six distinct categories of excavation, the New Austrian Method of ground support was utilized throughout.

Jan 1, 1993

By P Albert

A wedge-shaped underwater rock plug has to be blasted in order to tap the reservoir and furnish water to a new underground powerhouse at Manicouagan-5. The paper deals with the design and engineering aspects of drilling and blasting of this plug where the topographical configuration is extremely difficult. In this study small diameter vertical holes are considered with the OD-method and a fixed platform is recommended for drilling and loading operations.

Jan 1, 1984

By Rob Grant, Manuel Lopez Cano, Mike Briggs, Ken Fletcher

The scorched desert sands and life giving waters of the River Nile in Egypt have been the back drop to awe inspiring engineering feats for over 4,700 years. The latest engineering marvel to grace the land of the Pharaohs is the Mubarak Pumping Station Project at Toshka. This ambitious project aims to open up an area of 607,000 hectares (1.5 million acres) of barren desert to irrigation based farming with the supply of 29 million tonnes (32 million tons) of water per day, drawn from Lake Nasser on the river Nile. It is anticipated that this currently unpopulated area of southern Egypt will soon flourish and become home to several million Egyptians who will conduct their lives around the water supplied by the 230 kilometers (144 miles) of concrete canals. An integral part of the pumping station is the intake canal. The canal was excavated in two sections – the dry excavation, and the wet excavation. The wet excavation comprised of some 5.5 million cubic meters (7.2 million cubic yards) of rock to be drilled, blasted, and excavated, from the surface of the lake. The challenge at hand was how to achieve this safely, quickly, and cost effectively, with water depths of up to 45 meters (148 feet), excavation depths of up to 47 meters (154 feet), blast production rate peaks of up to 30,000 bank cubic meters (39,200 bank cubic yards) per day, blistering summer air temperatures up to 60°C (140°F), and security concerns about the storage of large quantities of explosives in the Middle East region. The solutions to these challenges were engineered by UEE Explosives and centered around the use of a microgel bulk explosive called Rioflex™ and an international team of engineers and operators from three continents. The microgel and accompanying pumping system allowed pumping rates of up to 17,400 kg (38,400 lb) per day, and more importantly, enabled the bulk product to remain as an oxidizing matrix whilst in transport and storage, transforming into an explosive only moments before being pumped into the blastholes. This case study outlines the underwater drill and blast process employed at the Mubarak Pumping Station Project at Toshka, and the novel solutions to the unique challenges encountered.

Jan 1, 2004

By Robert A. Farnfield

This paper outlines the theory behind transfer functions and illustrates their application in the prediction of structural response to blast induced ground vibration. The ability to predict the response of a structure to a recorded ground vibration is desirable for a number of reasons.

Jan 1, 1994

By Baron Fidler, Dave Lilly, Matt Budin

Cumulative sum (CUSUM) statistical process control methods have been used in many industries to monitor quality control results. CUSUM charts are a method to determine when small changes in data indicate a major change in results. E.S. Page at AT&T developed the method in 1954. In many blasting situations, vibration and air blast readings vary slightly from blast to blast. Whether the change is significant or not can be hard to interpret from the raw data. CUSUM charts can assist in determining whether a major change is taking place and when the change began.

Jan 1, 2009

By Gerald R. Coonan

Early in the open session of the 1979 SEE Fifth Conference panel discussion, someone asked a question of the panel concerning the future intent of the Office of Surface Mining and the regulatory limits established for ground vibration and air blast. The "gist" of the question was: "What assurances do we have that OSM will not promulgate a limit of 0.5 inch per second ground vibration, or some other number within the next two years or so."

Jan 1, 1979

By Frank Hirthammer

"Nowadays, security in the lifecycle of explosives is more important than ever. Terror attacks all over theworld pushed the EU to decree a Commission Directive for the identification and traceability of explosives that set a series of requirements for involved manufacturers, distributors and end-users. The challenge was to find and implement a track and trace system for all concerned European companies byApril 5, 2015. Since then, countries worldwide have followed this example and implemented similarregulations."

Jan 1, 2017

By Catherine Johnson, Barbara Rutter

The shock tunnel located at the Missouri University of Science and Technology Experimental Mine is 65 feet 9 inches (20.0406 m) in length. The tests performed inside of this tunnel are either arena tests or shock interaction and transfer (SIT) tests. Arena tests simulate a large open air blast, with lower explosive weights, by elongating the impulse of the blast wave. SIT tests are conducted to determine how the produced shock wave interacts and transfers its energy into a target object located at the end of the tunnel. The target used in this research is multilayered, with each layer being a different material. The targets are 2 ft. by 4 ft. (0.6096m by 1.2192m) pieces of Medium Density Fiberboard (MDF), DOW polystyrene foam insulation, and gypsum drywall. The order of these materials varies with each test. This shock tunnel is unique, because the geometry changes along its length. To fully understand how the shock waves are affected by these changes, a working model was needed. The second purpose of this model is to confirm the maximum charge size of 400 grams (14.11 oz.) of C4 that can be detonated inside the tunnel without causing damage to or failure of the tunnel, thus reducing the amount of time needed in downtime and repair. The model predicts pressures in various locations both within the tunnel and the attached target, thus assisting in determining where failures would likely occur. In the process of generating this model, several problems were encountered, including filling the tunnel with air, meshing the complex geometry, and creating the tunnel in a CAD system. This paper will discuss how these problems were solved. A working model was created by using ANSYS Explicit Dynamics and ANSYS Autodyn. The tunnel geometry file was created using SolidWorks and includes the complex geometry changes along with the target and its mount located at the end of the tunnel. The results produced by the model were compared to the field SIT tests. The comparison of the results from both the model and the experimental testing showed a similar trend in the pressure traces.

Jan 1, 2018

By Gary Anderson, J. P. Remi Proulx

Rio Tinto’s Colowyo Coal Mine produces 2.1 million tons per year in northwest Colorado. Colowyo uses the terrace mining method to recover up to seven coal seams ranging in thickness from 5 to 20 feet. Coal recovery in the 6 foot thick high grade C-seam has recently been challenged due to large variations in the pitch and roll of the seam. As well, some coal damage was seen due to an increased thickness of the overburden consisting of a hard sandstone channel.

Jan 1, 2012

By Virgil J. Stachura, Larry R. Fletcher, Paul V. Sterk, Matthew N. Plis

The large diameter blastholes now being used in underground mining have caused concern because of their increased potential for damaging openings and creating rockfall hazards. In response to this situation, the Bureau of Mines is conducting research to reduce the amount of overbreak and damage to the perimeter of underground openings. This paper presents the results of tests with decoupled charges in 6.5 inch diameter blastholes, and unloaded guide holes, in Vertical Crater Retreat (VCR) stope panels at the Homestake underground gold mine in Lead, SD.

Jan 1, 1991

By Shao Li, Chen Zhiming, Wu Jihong

In this paper,powder emulsion explosives,which have high sensitivity and strong detonation force,have been studied by applying emulsion technology to the production of the present powder ones.Under the condition of #8 industrial detonator initiation,the distance of air gap propagation is 110~180mm,brisance !3.5mm, lead block test value 325ml and detonation velocity 3000~4000m/s for small diameter (35mm) explosive cartridges.In addition to these,the factors effect on are investigated by experimental study and theoretical analysis.

Jan 1, 1991

By William Reisz

Managing the blast site at almost any operation can be a daunting task. There are so many details that must be observed, understood, and acted upon. It goes without saying that there are no two locations that have the exact same challenges and concerns. The level and the extent of these challenges can vary widely.

Jan 1, 2014

By William Reisz

The explosives and blasting industry has a commendable safety and security record, especially over the last several decades. This is due in large part to our newer technologies, better training and education, engineering practices, corporate initiatives, our professional organizations, and whether we like to admit it or not - our regulatory agencies.

Jan 1, 2012

By Italo Onederra, Jason Furtney, Ewan Sellers

The Hybrid Stress Blasting Model (HSBM) is a high level blast modelling research tool which provides results that can still be used implicitly for practical blast design. The code is being developed through an international collaborative research project funded by a consortium of companies which is comprised of explosive, equipment suppliers and major mining houses. A key component of the HSBM is the numerical code and user interface designated as Blo-Up 2.5. To date validation work has focussed on breakage, fragmentation and damage outcomes in controlled laboratory experiments and using large concrete cubes

Jan 1, 2012

By Guo Ziqing, Tang Qiuming, Liu Yuanyuan

The channel-type non-mechanical stirring production process is a new developed technology for emulsion explosives in recent years. It removes traditional equipment such as mechanical-mixing emulsification, mechanical-mixing sensitization, matrix pumping, and explosive pumping, and has been applied in China. This technique achieves a fusion of higher intrinsic safety and lower cost, as well as the excellent quality of products and high efficiency of production. The emulsion particle diameter is about 0.5μm. The storage period of emulsion explosive produced with span-80 emulsifier is more than 7 months.

Jan 21, 2025

By G. A. Walsh, M. Timm, S. M. Geerts

This paper will discuss the effectiveness and the general use of improvised shaped charges. Testing was conducted by the New Mexico Tech Student Chapter of ISEE and held at EMRTC. The first series of tests conducted was to illustrate the performance of different features of the shaped charge. A PVC pipe filled with C4 with no cavity, PVC with an unlined conical cavity, PVC with a copper lined conical cavity and no standoff, and lastly a PVC pipe with a copper lined cavity and a 1.5 cone diameter standoff.

Jan 1, 2010

By Joseph W. Hejny, Marlyn G. King

Coal mining in the Powder River Basin has changed in recent years to accommodate the large quantity of coal produced. With strip ratios of one to one and up to three to one, extensive amounts of overburden have to be removed to get to the large thick seams of coal. Larger shovels and trucks have been implemented in the removal of this overburden. The addition of draglines and continuous miners have been added to increase the production of coal. Drills used today are capable of drilling up to 13.5 inch blast holes.

Jan 1, 1994

By Michael J. Sapko, Eric S. Weiss

The U.S. Bureau of Mines has been conducting research on the secondary explosion hazards associated with the mining of oil shale under gassy mine conditions. Explosive incendivity tests have been conducted in a 28 m~3 (1000 ft~3) gallery to evaluate the relative incendivity of experimental emulsion-ANFO blends. The incendivity was measured by determining the minimum inert stemming requirements for preventing the ignition of a methane-air atmosphere by the discharge of hot detonation products from a 5.7 cm (2.25 in) diameter borehole.

Jan 1, 1990