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By John E. Wiegand

This study will discuss the AMAX Coal Co., Penndiana Pipeline Project, which was conducted in conjunction with the following parties: AMAX Coal Industries, (U.S.B.O.M.) United States Bureau of Mines, (I.D.O.R.) Indiana Division of Reclamation, Ohio Valley Pipeline, Inc., New Mexico Tech, and ourselves, VIBRONICS, INC., Evansville, Indiana. The purpose of this study was to find a safe vibration level for active gas transmission pipelines near surface coal operations.

Jan 1, 1994

By David S. Shatzer, Michael R. Purcell

Current world events have demonstrated the use of commercial vehicles, other unconventional modes of transportation and unusual materials as explosives or incendiary weapons, affecting commerce, disrupting cities and even entire societies. Since the implementation of the Organized Crime Control act of 1970 the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has been investigating and studying explosives and incendiary devices and their related effects.

Jan 1, 2004

By Joshua Micah Hoffman, Jhon Silva-Castro, Kylie Larson-Robl

A coal mine impoundment failure has the potential to be environmentally devastating and life-threatening. It is well documented that after seismic events slope failures in impoundments can occur. It has been concluded that often the main driven factor of the failure is the increase in excess pore pressure due to ground vibration. A small amount of research has been done regarding the stability of coal mine impoundments under natural seismic events; however no research has been done considering vibrations from mine blasts. If it is taken into account that current environmental restrictions oblige to increase the capacity of coal mine impoundments, thus increasing the hazard of such structures, it is necessary to evaluate the effects of near-by mine blasting on the stability of the coal mine impoundments in order to mitigate and control the potential of slope failures. To study the behavior of excess pore pressure under blasting conditions, scaled simulations of production blasting events were set up inside of a controlled sand tank. The research was divided in two stages. The first one was done, using dry conditions, while in the second part, the same set of tests were performed under saturated conditions. This document shows the partial results for stage one (dry conditions). For the tests, explosive charges were set off within the sand tank at various distances to simulate different blasting distances. Information was collected from geophones, accelerometers, microphones and high speed video camera for dry and saturated scenarios and additionally from piezometers under saturated conditions to assess the behavior of the material under blasting conditions.

Jan 1, 2015

By C. Pelley, S. Kelebek, P. D. Katsabanish, M. Pollanen

A series of small scale tests have been conducted to evaluate the effect of blasting on the grinding resistance of rocks. The samples consisted of homogeneous blocks of granodiorite and limestone while blasting was performed using single and multi hole configurations. Grinding resistance was evaluated using relative ball mill tests, rod mill tests and the SAG Performance Index test (SPI) developed by Minnovex. It was shown that the grinding resistance was affected by blasting. However the effect depended on the final product size. In the case of the coarse grained granodiorite, a negligible effect was observed for grinding below the natural grain size of the rock, while the fine grained limestone exhibited more significant changes, in the range of 13-16%. Grinding of granodiorite in the coarse size range indicated a general reduction of its work indices, as evidenced by the results obtained from the ball mill, the rod mill and the SPI tests.

Jan 1, 2004

By D T. Froedge

Before this study was started, literature was searched and cases of alleged water well damage were investigated. Occurrence of ground water in Appalachia is primarily in low yield, fractured, water table aquifers. Four test sites were chosen based on geographic and geologic diversity. Test wells were drilled at each site and base line data on water quality, static water level, and drawdown characteristics were obtained before surface mining commenced. Blast-induced ground vibrations were measured at the surface by the wells at levels up to 5.44 inches per second maximum resultant particle velocity. Measurements made at the bottom of wells indicated that vibrations were considerably attenuated at depths of 140 to 160 feet.

Jan 1, 1983

By N L. Thomas

Hole size affects many factors which directly influence fragmentation in the muckpile and hence, the cost effectiveness of the entire operation. These factors include production capability, explosives and accessories efficiency and usage and drilling accuracy. In addition, hole size should be chosen to suit the geological conditions. The paper concludes that the optimum hole size is generally the largest that can be used commensurate with production and environmental considerations.

Jan 1, 1986

By Roger L. Keller

Cautious, productive blasting is employed in the adaptation of a mobile crushing system extending into a highway through cut. In Hong Kong's final chapter of infrastructure development in preparation for handover of sovereignty, the vital link to the new governing country, The People's Republic of China, is now being completed. The Ting Kau approach and Tai Lam tunnel involves the removal of 6 million cubic meters of rock by drill and blast means. For the main-cut excavation (because of removal Iogistics) a unique adaptation of a Lokotrack crushing and conveyor transfer system is being used. The characteristic narrow working area associated with through cuts, positioning of equipment, and production demand place many limiting factors on blasting. Add to this the strict criteria set by the local regulatory body, the Hong Kong Mines Division, and nearby vibration limiting structures (13mm/sec), has led to highly cautious, fine-tuned blasting.

Jan 1, 1998

By Craig Wilbour, John Stimberis, Rob Gibson, Lee Redden

An avalanche is a snow slide. A simple explanation is that the snow on a slope will slide (avalanche) when the snow strength can no longer support its own weight. Snow avalanches happen when the load from snowfall or ram on a snow slope increases faster than the stre n g t h of the bonds between snow crystals. Avalanches can also happen when the strength of a buried layer decre a s e s . Active avalanche control is the intentional triggering of slides. Washington State Department of Tr a n s p o r t a t i o n (WSDOT), does avalanche control to minimize the chance of natural avalanches into traffic. Avalanche control work is done all over the world by: highway departments, ski resorts, railroads, mining operations, utility companies, and other activities threatened by avalanches. The majority of active avalanche control is done with skis, by explosives, or exploding projectiles. Blasting techniques and practices have evolved to fit the specific needs of avalanche contro l . Passive avalanche control is the use of engineered s t r u c t u res such as snow sheds, bridges, or snow supporting devices, to permanently protect a specific location from avalanches. The problem is that these struct u res are extremely expensive. There are a variety of passive avalanche control measures as well as the active m e a s u res used to protect the highway over Snoqualmie Pass. As traffic volume and use expectations incre a s e , m o re extensive passive measures will be needed to keep avalanches from affecting the highway.

Jan 1, 2004

By Craig Wilbour, John Stimberis, Rob Gibson, Lee Redden

Active avalanche control is the intentional triggering of avalanches while people are kept out of the hazard area. Explosives are frequently the most effective tool for triggering avalances. In a highway setting an avalanche control program will reduce total highway closure time, while providing greater safety to motorists and maintenance personnel. Avalanche control with explosives is effective when the snow is somewhat unstable and almost ready to slide naturally. Forecasting this condition involves having a network of local meteorological stations, examining snow structure, using mountain weather forecasts, doing snow strength tests, and having the results of ski and explosive tests. The method of delivery of explosives to an avalanche starting zone is governed by the accessibility of the starting zone. Common methods include; hand placing or throwing charges, remote delivery cableways, or "trams", surplus military weapons, and a compressed gas charge launcher, or "Avalauncher". Charges dropped from helicopters are also occasionally use. We have increased the effectiveness of our program by use of large elevated charges. Efforts are being made around the world to develop and utilize better methods for the safe, remote initiation, but procedures have varied dramatically between individual control programs. There is now a movement to review and standardize operational guidelines for avalanche control. Highway avalanche control is often done at night, during winter mountain storms. Heavy rain or snow, high winds, and high avalanche hazard, are common work site conditions. Commercial and economic pressures are increading, so methods that redice highway closure time are important. There are also many safety issues to be addressed in avalanche control work.

Jan 1, 2002

By S. Mansfield, A. Sharma

At a large open cut copper mine, in pit crushing and conveying is used to shorten haul routes and minimise stockpiling of ore. This strategy decreases capital expenditure by reducing the number of haul trucks and excavators required and reduces the need to rehandle ore from stockpiles with a secondary load and haul fleet, with an overall goal of lowering operating costs and carbon emissions. As the mine has developed and expanded, it was necessary to extend the conveying network and install a fourth, semi-mobile crusher to increase the output of the operation, while maintaining the operational efficiencies. This required the blasting of a new tipping bench and pocket for the installation of one of the largest and most powerful semi-mobile, crushing plants. Fed by 360 tonne (396 ton) ultra-heavy class haul trucks, the KB 63-130 Pro gyratory crusher is the highest capacity available in the market. This paper describes the holistic process that was applied to model, design and execute the blasts required to create the pocket for the semi-mobile crusher, the surrounding tipping bench, plus the conveyor corridor and access ramp used by the ultra-heavy class trucks.

Jan 1, 2024

By John Norman

This paper will cover blasting techniques that are applicable to underground and other rescue that involves removing obstacles and breaking rock in close proximity to rescuers and subjects.

Feb 1, 2020

By Jay Smerekanicz, Florin: Pedersen Gheorghiu, Alan Cameron

In order to expand the capacity of Modern Landtill, a groundwater extraction system consisting of a linear system of pumping wells over 2,700 feet long had to be replaced. The new system would be covered by landtill cells to a depth of approximately 400 feet, and therefore would have to be maintenance free. In addition, the new system had to be proven to be more effective than the previous system, groundwater extraction had to be maintained during construction and construction could not disturb either the landfill operation or nearby residential neighbors.

Jan 1, 2001

By James E. Jr Hargroves

With the ever-increasing population growth and modern trend to urban development, the expansion of utilities is a stable, mad or, and constant source of income for many. Blasting is a "necessary evil" to the utility contractor. It can make or break even the most solvent. Housing development expansion and higher treatment of effluents are causing utilities to appear in more congested areas. This paper discusses some of the aspects of utility blasting in the State of Virginia. Consideration is given to bid procedures, pre-blast surveys, record-keeping and practical application.

Jan 1, 1977

By Kurt Oakes, John Williams

Placer Dome, US operates the Bald Mountain Mine. The Bald Mountain Mine is a surface operation located in remote northwestern White Pine County in east-central Nevada, approximately midway between Elko and Ely. The mine is in the Newark Valley along the southwestern flank of Bald Mountain a part of the Ruby Mountain range, at an approximate elevation of 7,500 ft (2,286 m). The geology at the Bald Mountain Mine is highly altered, both mineralogically, and structurally. Highwall stability and control have long been an issue at the operation, due largely to the varying geologic conditions. In some blasts as many as seven distinct geologic unconformities exist. These unconformities affect both final high wall integrities, as well as blast fragmentation characteristics. A 60 million ton (54.5 million tonnes) layback expansion of the existing “Top Pit” as well as development of a new satellite pit, “Sage Flats”, is being undertaken. Design final highwall pit slopes have been steepened from the traditional 47º to 55º in order to reduce overall ore-to-waste ratios, thereby improving economic viability for the expansion over the 4.5 year life of the project. With the increased usage of electronic detonators throughout the mining industry, mine operations staff, as well as representatives from the mines explosive supplier felt that an evaluation program incorporating electronic detonators would be warranted. The areas of focus for this evaluation would be resultant highwall pre-split integrities, peak particle velocity measurements (both near field and far field), frequency measurements, loader productivity, and visual interpretation of the results. The mine incorporates 25 ft (7.6 m) benches and uses separate trim blasts in conjunction with production blasts in order to reduce blast effects along final highwalls. Hole diameters in production blasts are 7? ” (200 mm). Typical production blast patterns are 18 ft x 18 ft (5.5 m x 5.5 m), drilled in a square pattern configuration. Shot sizes vary greatly, ranging from 200 holes to as many as 800. Bulk low percentage ANFO/emulsion blends are utilized as the redominant blasting agent. Non-electric dual delay detonators (25 ms/500 ms), with non-electric surface delays are the initiation system utilized in production blasts. Typical production blast design

Jan 1, 2004

By Alain Blanchier, Anne Charline Sauvage

Rock mass variations have a huge influence on explosives efficiency and on blasting results. Numerous blasting improvements could be gained by taking into account rock mass and its variations. However, extracted rock mass is generally considered as statistically homogenous. The development of a panel of pre-blast survey procedures that every blaster can use, consists in the realization of a process integrated into every day work: for example as well as toe burden or blast hole depth, discontinuities spacing or the weathering expanse have to enter in rule book, if it provides blasting efficiency and security improvements.

Jan 1, 2004

By Ray Patterson

A planned modification to a cement kiln at the Holnam Portland Cement Plant near Florence, Colorado required the removal of a ring of cast-in-place (CIP) refractory lining. The CIP lining was approximately 14 inches wide, 12 inches thick and 38 feet in circumference.

Jan 1, 1999

By Charlie Brumbaugh

Antarctica with its diverse conditions such as severe cold, high winds, rock and ice structure and limited explosives available posed many obstacles. This paper will give an overall view of the methods used to overcome these obstacles on a daily basis on the highest, driest, coldest continent on earth.

Jan 1, 2000

By Richard Goodridge, Stephen Thomsqn, S Rodgers, D Tunaley

The mining, quarry and construction industries are facing’new challenges everyday. These challenges can be imposed by economic objectives or through external factors such as extreme geological conditions. Simultaneously, all mines, quarries and construction sites are facing more and more stringent environmental requirements.

Jan 1, 1998

By Radhe Krishna, Mutale William Chanda, Timothy Mwale

Blasting as a process is the emplacement of industrial explosives into blast holes suitably located to a free surface and detonated. Every blast hole containing a certain amount of explosive charge undergoes impulsive loading when detonated and results in the dynamic transfer of a powerful shock wave to the surrounding rock. It is the shock wave that brings about rock breakage when the tensile stress produced upon reflecting from the change in material density or free face overcomes that of rock material tensile strength. However, this shock wave comes along with unwanted destructive consequences such as damage to remaining rock, ground vibration, noise and fly rock. The above mentioned consequences pose a great threat to the Community of Wusakile, Kitwe as Mopani Copper Mines Plc wishes to increase its production by expanding the pit towards the community that lies within 150 m (164 yd) from the pit rim. As a requirement from the Zambia Environmental Management Agency (ZEMA), all blasting operations close to the community must maintain at least below the maximum vibration threshold of 10 mm/s (0.3937 in/s) PPV-Peak Particle Velocity or else risk closure of the mine (AMC,2009). In order to satisfy the above statement, a good understanding of explosives is required. This paper therefore presents the phenomenology of rock breakage by explosives with much emphasis on electronic blasting and how best this process can be controlled in densely populated communities. Factors affecting maximum projection distance such as, size of the fragment, shape of the fragment, angle of projection, the state of confinement of an explosive charge, were also studied. In addition, design faults, deviation in implementation and unforeseen geological conditions were also considered. The paper discusses the above facts based on research.

Jan 1, 2015

By David Miller, James Santoro

Blasting is often required in urbanized areas to allow for economical execution of construction, demolition, and mining. Several examples of operations that require blasting in built up areas include: rock blasting for foundation and utility excavations; surface and underground mining for mineral extraction; and explosives demolition. Although explosives demolition is an engineering discipline, not at all like rock blasting, it still uses explosives for the felling of structures that have outlived their usefulness. Through the use of modem technology and implementation of extra safety precautions, explosives are used safely in congested areas to make the performance of critical work economical and feasible. This paper discusses several precautions required when undertaking various types of rock blasting and explosives demolition in congested areas. It also presents the adverse effects that must be considered when blasting in congested areas. The effects identified include flyrock, vibration and airblast, fumes, and non-elastic (permanent) ground deformations/overbreak. Measures for mitigating and controlling these adverse effects to provide on-site and public safety are presented.

Jan 1, 2000