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By Douglas R. Burns

Complying with SARA-Title III and the Emergency Planning and Community Right-To-Know Act as a Non-Manufacturing Facility. As of August 23, 1988 non-manufacturing facilities storing end using chemicals which require MSDS (Materia1 Safety Data Sheets) must fi1e with SERC (State Emergency Response Commission), the LEPC (Loca1 Emergency Planning Commission), and the loca1 Fire Department a list or copies of all MSDS sheets with the Tier I and Tier II forms completed.

Jan 1, 1989

By C H. Dowding, P W. Linehan

Many of the technical and non-technical or human problems associated with blasting can be minimized through a proper preconstruction test-blast program.

Jan 1, 1986

By Henry P. Van Ormer

This paper discusses some basic fundamentals in compressed air system design and layouts that should always be considered in planning or evaluating a compressed air distribution system in Construction and Mining. Often times, mining operations use central air or "power house" type systems that more closely resemble a typical industrial or plant compressed air distribution system. This paper does not attempt to cover this type of system.

Jan 1, 1975

By Jason M. Ryan

"Along with recent advances in computer technology have come cost-effective systems desiiedto evaluate fragmentation distributions through digital images of particles. In mining operations andmineral processing plants, important data from these systems is obtained through monitoring sizedistributions at key stages of the comminution process. Blast engineers apply this technology as atool for the validation of empirical fragmentation models so that predicted results are more meaningful."

Jan 1, 1998

By Estefania Aramayo, Jhon Silva, Todor Petrov

Blasting is one of the most critical activities in a mining operation. Nowadays, many quarries have to follow a considerable quantity of environmental restrictions that drive the need to improve the conceptualization, design, procedures, and execution of the blast to comply with all regulations. Airblast is one of the variables required to control when blasting. Airblast is an unwanted side effect of blasting. Airblast is defined as an airborne shock wave resulting from the detonation of explosives. Traditional methodologies used for assessing the overpressure produced by the airblast are based on empirical approximations that require the collection of a series of produced airblasts before they can be used as a predicting tool. Once the data is available, regression analysis methodologies are used to find the constants of empirical laws that, in most cases, establish the relationship between the distance and the weight of explosives used in the shot (scaled distances laws). If using the traditional methodologies, the quality, and representativity of the scaled law established for a particular project are determined in terms of the correlation coefficient; in most cases, the models and their use as a predicting tool are questionable (very low correlation values).

Feb 6, 2023

By J L. Jethwa, A G. Gaithankar

The paper deals with a software method developed to design the optimum blast parameters for tunnels and mine roadways for a given set of geo-mining condition without any major discontinuity. The application of the software is presently limited to 8 D-ahaped excavation where inclined hole cut or four-section parallel cut is used with smooth blasting technique.

Jan 1, 1993

By Dave Proudfoot, Mike van Wyk

"There has akvays been plenty of discussion around the ‘accuracy of pyrotechnic detonators withmost recognised manufacturers claiming a variability of arourid 1% or less for their ‘superaccurate’ pyrotechnic based detonators. It is only now being understood that this 1% variabilitycan have serious adverse effects on blast performance. For example a 1% accurate 500millisecond shock tube detonator can fire anywhere between 485ms and 515ms. When wecouple these rather inaccurate ‘accurate’ detonators with short delays on surface, such as a 17millisecond connector, the probability of delay crowding and even out of sequence firing is quitehigh."

Jan 1, 1998

By Calvin Konya, Theodore R. Myers, Robert Lundquist

The design of a single, large mass blast using ring drilling may take two to three months. This time requirement inhibits the evaluation of multiple designs. It also reduces the flexibility to redesign a blast when a parameter affecting the blast changes. Manual preparation exposes the design of a ring blast to a greater probability of human error. The use of Computer Aided Design (CAD) can help to overcome the shortcomings of manual design preparation. High speed electronic calculation, as well as programming, allow for many designs to be considered before blasting. Parametric programming allows single or multiple parameter changes to be introduced into an existing design, such as changes in drilling equipment, variations in ore density or changes in explosive. Exposure to human error is reduced by programming that performs calculations and produces graphical displays for review by the designing engineer. The goal of achieving desirable fragmentation for the minimum cost, when using ring blasting, is obtainable using blasting design techniques and CAD. Multiple designs can quickly be generated and costed, producing cost curves that indicate an optimum design with respect to cost.

Jan 1, 1990

By Neil T. Davie, Thomas K. Blanchat, Thomas C. Togami, Joe R. Weatherby, Dale S. Preece, Robert A. Benham, James J. Calderone

"Geotechnical structures ,such as underground bunkers, tunnels, and building foundations aresubjected to stress fields produced by..the gravity load on the structure and/or any overlyingstrata. These stress fields may be.. reproduced on a scaled model of the structure byproportionally increasing the gravity field through the use of a centrifuge. This technology canthen be used to assess the vulnerability of various geotechnical structures to explosive loading.Applications of this technology include assessing the effectiveness of earth penetrating weapons,evaluating the vulnerability of various structures, counter-terrorism, and model validation. Thisdocument describes the development of expertise in scale model explosive testing ongeotechnical structures using Sandia’s large scale centrifuge facility. This study focused onburied structures such as hardened storage bunkers or tunnels. Data from this study was used toevaluate the predictive capabilities oft existing hydrocodes and structural dynamics codesdeveloped at Sandia National Laboratories (such as Pronto/SPH, Pronto/CTH, and ALEGRA)."

Jan 1, 1998

By Thomas H. Kleine, Alan R. Cameron, William W. Forsyth

In general the software required by a blast designer includes tools that graphically present blast designs (surface & underground), can analyze a design or predict its result, and can assess blasting results. As computers develop and computer literacy continues to rise the development of and use of such tools will spread.

Jan 1, 1995

By S Burchell

During the past few years, high-speed cameras, laser surveying equipment and photogrammetry have become standard tools for recording blast geometry and results. While laser profiling yields accurate 3-D measurements, most cameras capture only two-dimensional images. Attempts to extract 3-D information from photographs have been unsatisfactory. Recent advances in electronic imaging and computer programming have made it possible to develop a 3-D computer based analysis system which can capture and measure 3-D images quickly and accurately. This paper describes the technology to create 3-D images and to analyze blast geometry before, during and after the blast.

Jan 1, 1992

By Mike McGill, Stephen Chung, Dale S. Preece

Cast blasting can be designed to utilize explosive energy effectively and economically for coal mining operations to remove overburden material. The more overburden removed by explosives, the less blasted material there is left to be transported with mechanical equipment, such as draglines and trucks. In order to optimize the percentage of rock that is cast, a higher powder factor than normal is required plus an initiation technique designed to produce a much greater degree of horizontal muck movement. This is a significant change from normal blasting practice where fine fragmentation and sufficient muck movement were the prime requirements to permit efficient excavation.

Jan 1, 1994

Coal strip mine operators in Western Canada often mine steeply-dipping multiple coal seams in mountainous terrain. The ability to fragment the rock waste layers above and below these seams with minimum disruption of the seams in large blasts normally involves decked charges in large rotary boreholes. Mining these seams may take two or more separate blasts to break the waste wedges above and below the coal, but these wedges can be blasted in a single shot for better mining efficiency.

Jan 1, 1985

By Lindsay Wade, Peter Dare-Bryan

Benches in surface mines often contain known areas of ore and known areas of waste, which must be mined selectively. When rock is blasted it not only fragments but is also physically, and non-uniformly, moved. Risks therefore exist of ore being lost if treated as waste and of mill feed being diluted by waste. Both possibilities carry serious fmancial implications.

Jan 1, 2001

By G K. Jorkenson

Blast designs to cast a percentage of overlying waste rock off coal seams differ greatly from conventional blast designs for surface coal mines. Today, blasting engineers can benefit from computer simulations to test various blast designs and reduce cost and time spent on the old trial-and-error method.

Jan 1, 1989

By Gungor Tuncer, Erhan Bakirci, Ali Kahriman, Atilla Ozmen, O. Nuri Ucan, Savas Gorgun

There are several methods for demolition of structures but most of them depend mostly on conventional ways of using machines for breaking and crushing structural elements. However the need for lots of work force, expense and extreme amount of time for demolition, made most of these methods non-popular nowadays. Therefore, trials to accomplish a more economic and less time taking method lasted with the use of blasting. By applying controlled blasting on a suitable structure, the structure can collapse and break down to pieces in very short period of time, with no extra work force and cost. In spite of advantages of explosive demolition, the potential danger of explosives and the damage that the blasting may cause to surrondings, if not controlled properly, made people timid to the method especially in urban areas. Therefore, the pre-assumption by computational analysis has become an essential matter in the process.

Jan 1, 2002

By Mark S. Stagg, Rolfe E. Otterness, Stephen A. Rholl

The Bureau of Mines has developed computer software to study the effects of initiator scatter on all aspects of the blasting process. The software is useful because it is difficult to obtain actual initiator data, particularly the standard deviation which is needed to express initiator scatter. The new software is structured to allow blasters to answer the question: how precise must initiators be to insure a successful blast? Successful is defined statistically in terms of a confidence level. The software can be used with any possible design since there are no restrictions due to size or complexity.

Jan 1, 1992

By G E. Exedaktylos, Y Zhou

The complex and non-linear nature of blast fracturing has restricted common bract design primarily to empirical approaches. The code developed for this investigation simulates the pattern of interacting radial fractures from an array of blastholes, at various burdens and spacings, and in simultaneous and delayed modes. The resultant pattern is analyzed and a fragment adze distribution calculated.

Jan 1, 1989

By William Wilkinson, Vladisla Kecojevic

Current three-dimensional (3D) computer design technology leveraged into drill and blast planning and operations is changing the way engineers and operations approach drill and blast design. Additionally, Global Positioning Systems (GPS) technology that is now readily available to the civilian population is being implemented into the mining sector with a variety of new products specifically designed for drill and blast operations. The objective of this article is to discuss the steps involved with 3D Computer-Aided Design (CAD) of drilling and blasting, and the benefits such a design can provide in conjunction with GPS and drill monitoring systems.

Jan 1, 2004

By Neal Lee, Braden T. Lusk, Jhon Silva-Castro, Patrick J. Jenks

"Timing and charge sequence are very important for optimized blast design. Traditional nonelectricinitiation systems have moved the industry toward a system of delays consisting of hole-to-hole androw-to-row timing sequences that mimic the application of nonelectric surface delays or dual delayinitiator systems that have been prevalent in the blasting industry for many years. The increasedutilization of electronic detonators allows for the use of Regular Rhythmic Timing (RRT) utilizing onlyone delay between charges and a selected charge firing sequence. The hole to hole and row to row (HHRR) timing method has been utilized for blasting optimization and allows for simplistic changes to the tie in phase of the blasting sequence. When using this traditional timing methodology, for some specific cases related to the number holes and rows, crowding occurs in the delay between charges with subsequent increase in the peak particle velocity (PPV) produced by the blast. This is in contrast to RRT where the timing between the delays remains constant."

Jan 1, 2016