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By O E. Crenwelge

Seismograph measurements are usually made near blasting operations solely for the purpose of monitoring compliance with governmental regulations. However, recordings of seismograph signals have far greater potential than this, if the proper procedures are used for analyzing the transient data.

Jan 1, 1991

By Charles H. Dowding

This paper describes NUVIB, analytical software to digitize, analyze, display, and plot time histories generated by blasting and construction vibrations. It is available in conjunction with a new book on Construction Vibrations (Dowding, 1996) through internet procedures described at the end of the chapter on analytical software These internet based procedures eliminate the need for inclusion of disks in the book and take advantage of the growing electronic communications network. Perhaps more importantly this procedure allows the software to be updated more often than the book is reprinted.

Jan 1, 1997

By Wang Xuguang Shen Yingfeng

Structure is the main aspect affecting the performance of emulsion explosive. Calculation of such structure parameters as osmosis pressure, interface area per unit volume etc. must be helpful to the understanding of the structure of emulsion explosive. This paper has solved the Laplace-Young Equation for simplified monodisperse emulsion system by Galerkin method, and gained the relationship between mean curvature, contact angle, volume fraction, fractional film area and interface area per unit volume. The paper also presents a new expression of osmosis pressure at non zero contact angle.

Jan 1, 1998

By R Yang, D B. Kay

"Blast vibration control is of vital importance for tunnel blasting in urban environments. A vibration model with multiple seed waveforms (MSW) as input for a point of interest was developed in recent years by one of its authors. The MSW blast vibration model has been applied successfully in open cut and quarry blasting situations. From the literature, it appears that there may not be any seed wave-based vibration modelling work for tunnel blasting.A project was conducted to test the MSW model for tunnel blast vibration. A series of tunnel blast rounds were fired and tri-axial vibration waveforms from the blasts were recorded with several seismographs at distances ranging from 10 to 100 metres from the blasts. Seed waveforms were collected and the charge weight scaling law for the signature hole PPV were established.The MSW model is applied to tunnel blasting and specific issues associated with tunnel blast vibration addressed, such as variable effects of confinement and screening to vibration during a blast round. The capability of the model in terms of the PPV and frequency prediction is demonstrated in the paper. The paper demonstrates that the MSW blast vibration model is a useful tool for managing tunnel blast vibration with the potential to optimise round by round design in terms of managing the vibration below the limit while maximising tunnel advance rate."

Jan 1, 2011

By C. B. Navalkar

The optimization of blast design under consideration is for the conventional driveways in under ground coal mines with respect to board & pillar workings in India. Basically The Blast Design includes following parameters: AA> Drilling Pattern. BB> Charging Pattern. CC> Material & Method Of Stemming. DD> Selection of type & quantity of explosives. EE> Initiation system & Blasting Sequence.

Jan 1, 2002

By Roger N. Prescott

This report presents a new process in delay blasting with the use of ANFO and slurry explosives.

Jan 1, 1977

By Frank Wilder, Mark Ferrero

One of the challenges currently facing the explosives industry is how to transition its workforce and its business systems to respond to the increasing pressures for improved inventory and records management. The pressures applied by many U.S. federal and state agencies, such as the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) and the Department of Environmental Protection (DEP), as well as regulatory agencies around the world, are increasing the need for accurate inventory accounting of explosive materials and blast documentation. With blasting companies now facing regular documentation audits, potential liability issues may arise due to the inconsistent or missing documentation.

Jan 1, 2006

By Cam Grundstrom

The Ok Tedi Mine is a large open pit copper and gold mine located in a remote section of the Western Province, Papua New Guinea, with an annual rainfall of over 10 metres. Ok Tedi mines an average of 205,000 tonnes per day. A strong working co-operation between the mine operator (Ok Tedi Mining Limited) and the explosives contractor (ICI Explosives Asia / Pacific) has led to progressive development of bulk emulsion formulations to meet site-specific needs, continued improvement to blasting applications, and competency based training programs for the national blast crew.

Jan 1, 1997

By Ann Barron

Even though you think your company’s safety program is the best it can be, equipment, processes, supplies, surroundings and people do not always behave or react as expected. Consequently, needless accidents occur each year at quarries, construction sites, surface mines, and other locations where explosives are used. While blasting accidents account for only a small portion of the total accidents reported, the severity rate for blasting accidents is higher than for any other accident category.

Jan 1, 2007

By Gordon Revey

In construction and mining work, situations occasionally occur where hard rock or concrete must be excavated at locations near critical structures or utilities. Fearing damage from blasting, contractors and engineers often explore the viability of using mechanical methods or expansive concrete to facilitate the excavation work. However, for moderate to large excavations, the prolonged duration and high cost of using these methods is often impractical. In these situations, under the right conditions, controlled blasting and blast-management methods can be used to speed up the work and lessen costs. The process of determining whether or not blasting is practical is ofien complex, particularly when risks are high.

Jan 1, 2001

By Jim Daley

SEE is a dynamic organization composed of people from all facets of the explosives industry who are truly interested in the advancement of that industry. I had been a miner at the Homestake Gold Mine in Lead, SD for 12 years when I decided to obtain a mining engineering degree. The mental and economic consequences of that decision were more severe than we had imagined. The joint scholarship program of the Northern Plains and Black Hills Chapters of SEE provides assistance to several college students each year. I was fortunate enough to receive scholarships from this program twice and this assistance helped me and my family with both monetary and psychological support during times of need so that we could stay focused on the goal of obtaining a degree.

Jan 1, 1995

By Roger Holmberg, Dick Salomonsson

Nitro Nobel (the company was acquired by Dyno Nobel in 1986) originally developed non-electric initiation systems. These system were based on the 1967 invention of the shock tube fuse by Per-Anders Persson. Through licensees CIL and EB production and sales also started in Canada and the US. Early on, some accidental initiations of the tube occurred in production. It was found that static electricity was involved. After corrective action was taken - by changing the aluminium content in the tube core load - no further accidental initiations were reported until 1991.

Jan 1, 2002

By Duane A. Houkom

Explosive demolition of concrete has been accepted as a safe and economical means of concrete removal for many years. I imagine that the early concrete blasters were experienced rock blasters who applied their knowledge to just another formation. Since a concrete foundation is generally located in a congested area, the owner is willing to accept the higher costs of mechanical removal,rather than promote "a new idea" to his management. This attitude is rapidly changing,making it possible to use the advantages of explosives in more congested locations.

Jan 1, 1982

By Wang Hao

"Demolition of reinforced concrete frame structures in building crowded cities is a hardproblem in control blasting. Any mistakes, e.g. wrong toppling direction of multi-storeybuilding or incompleted blasting of structures will all cause terrible accidents.To demolishframe structures safely, various disciplines including structural mechanics, explosionmechanics, rock engineering, etc. are involved"

Jan 1, 1993

By Li Jianjun, Zhang Xiaozhi, Guan Li, Jin Jinzhe

People used to regard emulsion explosives as the safest industrial explosives. But in the process of manufacturing emulsion explosives spontaneous ignitions of the remnant emulsion matrix have happened under the conditions of constant or low temperature. These fatal accidents show both emulsion explosives and emulsion matrix may involve hidden danger. Since the temperature in its production emulsion matrix is high, emulsion matrix is sensitive to mechanic action.

Jan 1, 1998

By Alex Jankovich, Darren Thornton, Sarrna Kanchibotla, Cam Grundstrom

The Porgera joint venture and Dyno Noble have commissioned a joint project to optimise the drill and blast operations to increase the overall profitability of the mine. One of the aims of this project is to increase the throughput of semi autogenous (sag) mill by optimising the blast fragmentation, The work done so far clearly indicates that significant improvements in sag mill throughput can be achieved by optimizing the blast fragmentation. This paper discusses the planning, implementation and results achieved so far in this project.

Jan 1, 2001

By Ron J. Elliott, Corry Coumans

The following is a detailed description of the blasting procedures used in the successful demolition of the Stave River bridge, Mission, British Columbia, Canada. This highway bridge spans a highly sensitive salmon-spawning river. Demolition of the bridge took place in a high liability situation in close proximity to sensitive structures. The new highway bridge carrying an exposed 150mm diameter gas line was located only 1.5 meters away. The bridge piers were blasted only seven meters from overhead power lines. Control of blast vibration, flyrock, and underwater overpressure was critical to the success of the operation. Electrical sequential blasting was used to ensure that blast vibration on the new bridge structure was kept below 50mm per second.

Jan 1, 1998

By Diego Quezada, Carlos Munoz, Marco Arellano

It is well-know that the presence of fine materials in mining has a direct impact on the plant processes with a great influence in the total amount of ore production and recovery. In Cu mining heap leaching is affected negatively by the presence of fines material (< 100 # Ty) in leaching piles, where a decreasing in Cu recovery is achieved in a lot of cases. D&B practices used normally in mine operations can generate fines > 4% in blasted piles, but the principal effects are reflected in the downstream processes where pre-conditioning post-blast materials release greater quantities of fines.

Jan 1, 2010

By Vilem Petr

Optimization blast design parameters for rounds used at surface mines, quarries or cast blast has taken on a new importance with the increased the cost of the explosives and electronic detonators. This paper addresses the fundamentals of blast design and optimization explosive energy utilized for fragmentation. This laboratory studies shows that one key variable-the strain energy set up in rock mass by blast vibration – can be used to predict the extent of damage done to the rock strata, the degree of fragmentation of the broken rock, and the velocity of the broken rock. It also shows how the dynamic strength of the rock strata is influence the fragmentation size distribution as well as the blastability.

Jan 1, 2008

By Norman S. Smith, Richard L. Ash

Many factors affect rock fragmentation from blasting. One variable seldom considered when designing blasts, however, is the borehole length. An example is described of how the length was adjusted to give better breakage when using 4-inch diameter blastholes at a quarry. To explain the basic principles involved test results from experiments conducted by the authors where borehole lengths were altered are presented and evaluated.

Jan 1, 1976