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By A Brodbeck, AT Spathis

Australian regulatory control of ground vibration and airblast arising from mining, quarrying and civil construction operations is spread across a number of federal, state and local authorities and across a number of departments with various jurisdictions. The Australian Standard AS 2187.2 contains an informative appendix on damage-related criteria and it is the primary reference for the regulators. The complete standard and the informative appendix is currently undergoing major revision with a focus for the latter on implementing frequency-dependent criteria for ground vibration. Certain directions for change have been raised for consideration by the standing committee, ranging from fundamental issues of measurement and interpretation and others that overlap human comfort criteria. It is anticipated that some of the suggestions will eventually make their way into future standards after an adequate period of consultation and consideration by both the Australian public and others involved in the associated industries.

Jan 1, 2005

By James Rowland, Marcia Harris, Richard Mainiero

This paper reviews the potential hazards posed by the toxic fumes produced by detonating explosives in surface mining and construction operations. Blasting operations produce both toxic and nontoxic gaseous products; the toxic being mainly carbon monoxide (CO) and the oxides of nitrogen (NO x ). The quantity of toxic gases produced by an explosive is affected by formulation, confinement, age of the explosive, and contamination of the explosive with water or drill cuttings, among others. Techniques to protect workers and the public from the potential hazards of explosive-related toxic fumes are discussed.

Jan 1, 2007

By John R. Holliday, William Marcum

Apogee Coal Company, DBA Arch of West Virginia, faced the challenge of drilling and blasting over one million cubic yards of high temperature overburden at its Ruffner surface operation near Logan, West Virginia. The overburden was removed above the Upper Five Block seam that was previously deep mined, abandoned, and later engulfed by fire. Borehole temperatures were measured above 700” F.

Jan 1, 1996

By Sandra Penttinen

There are several ways to get a positive reaction from neighbors to blasting projects. When you need to enter structures to conduct a pre-blast inspection, the impression you make on the structure owner must be positive from the very start. Public relations with neighbors is the key. The purpose of all communications with persons residing near planned blasting operations is to educate structure owners as to what will take place during the blasting operations, to explain that safe blasting practices will be followed and vibration and airblast limits will be imposed to protect surrounding structures from damage. Once access into the structure is obtained, the structure owner can be shown, by careful documentation, all existing cracks and defects in the structure prior to blasting and construction. The objective of your visit and all communications is get your foot into the door and win the confidence of the structure owner so that he or she understands blasting will not compromise the structure.

Jan 1, 2006

By Johan Hawinkel

This paper explores the journey through time of technology in the civil explosives market to provide testing, measurement, analysis and control tools. This ultimately leads to better decision-making, ensures full accountability of the decision maker and uses the same technology to review decisions for process improvement, in the settlement of disputes or for the investigation of incidents. Additionally, the paper discusses the application and integration of electronic and digital technology in explosives and initiation systems as engineering controls for blasting associated risks.

Feb 1, 2020

By Davey Bickford, Johan Hawinkel

Blasting and the use of civil explosives are a critical step in the mining process. Good decisions provide significant downstream benefits and create a safe and sustainable working environment, while poor decision making and judgement can have catastrophic consequences on workers safety, critical infrastructure or the security of the general public. An ever-tightening regulatory framework increasingly exposes manufacturers, transport companies and mining companies to the consequences of breaches resulting from erroneous or ill-informed decisions. In this context, new capabilities are required providing all actors in the explosive supply chain with tools to make better informed decisions allowing the individual to own up to his or her decision. Additionally, the traditional risk-control approach in the explosive supply chain up until usage and waste elimination, through administrative control procedures and processes, is becoming increasingly inadequate. In this era of digitalisation and automation, technology will play a pivotal role in ensuring safety and security in storage, transport and usage of civil explosives using the latest advances in electronics, communication technology and information technology. This paper explores the journey through time of technology in the civil explosives market to provide testing, measurement, analysis and control tools. This ultimately leads to better decision-making, ensures full accountability of the decision maker and uses the same technology to review decisions for process improvement, in the settlement of disputes or for the investigation of incidents. Additionally, the paper discusses the application and integration of electronic and digital technology in explosives and initiation systems as engineering controls for blasting associated risks. Finally, this paper reviews two practical cases of technology integration for risk management and improved decision making; the use of integrated GPS technology in initiation systems as an engineering control in the blast evacuation process and the use of RFID technology in explosive tracking from cradle to grave.

By Victor C. Bryan

"One of the more challenging issues facing operators of U.S. mines and quarries is blasting in an environmentally acceptable way. It is quite important that industry management understand and apply guidance, discipline, and control in the exercise of blasting operations. This presentation is a discussion of problems related to that environment away from the blasthole that may or may not be adversely affected by blasting and the steps management may consider in resolving resultant problems. In any case, one of the main concerns that will continuously be brought up is thatmanagement procedures inherent to good blasting is a uxporate responsibility of the mine or quarry business entity; and can not be delegated to the explosive manufacturer or supplier. This management attitude, based on education, training, and the comprehension that the process of production begins with drilling and blasting and consumes a significant amount of overall production costs."

Jan 1, 1995

By Tianrui Xu, Chaohong Liu, Bangqing Ding

The authors were responsible for a series of large scale multiple chamber charge blasts conducted in the granite mountain area for making construction space on the southeast sea coast in China during 1993-1996. This paper describes the blast design and damage control of one mountain blast 320m in length and 280m in width in the vicinity of two wharfs and a dam. In order to obtain better rock fragmentation and muckpile, the explosive charge should be well-distributed in the mountain. The charge pattern, therefore, was designed with mainly 5 rows of tunnel charge in regular terrain in combination with a chamber charge in irregular topography area and the maximum burden was limited to be less than 38m. In order to protect the dam and wharfs the firing sequence was carefully arranged in 29 intervals and the distance between different charges of the same delay to the dam or wharf was taken into account as an additional delay interval based on the difference of p-wave propagating times. The maximum charge fired in an interval was also limited to less than 34t explosives through dividing the larger charge by a stemming deck.

Jan 1, 1998

In the office, on the wall to the right of my desk is a large map of the world. Some people stick pins in maps like this to show where they’ve been. If I did that my map would be a mess and look like a pin cushion. I was so fortunate to have been able to see how people live and blast in other parts of this beautiful planet. We l l , maybe some parts weren’t so beautiful and maybe some parts that were beautiful were hell holes for those living t h e re . Every time I re t u rn to the good old US of A, I say a small prayer in thanks for having been born and raised in a land of freedom and plenty. So many places and people have not been so blessed.

Jan 1, 2004

By Timothy Stark

Blasters are usually strictly liable for injury or damage caused by flyrock (trespassory invasion) and blast-induced vibrations (non-trespassory invasion). The application of strict liability to non-trespassory invasions has resulted in significant litigation that has hampered the use of blasting and the blasting industry. Stark (2002) proposes that blasters should not be held strictly liable for non-trespassory invasions but should be liable only if their conduct is proven to be negligent. This change in legal standard was proposed because improvements in blasting technology over the last thirty years allow blasting to be conducted without substantial risk of harm to property and thus the amount of harm imposed by a blast can be related to the level of care exercised by the blaster. It is anticipated that a negligence standard will reduce the amount of litigation because a plaintiff will have a greater burden to overcome. To facilitate the acceptance of a negligence standard by a court of law, this paper summarizes the standard of care using the 1977 Surface Mining Control and Reclamation Act, extensive U.S. Bureau of Mines research, and current blasting techniques, such as blasting mats. It is important for the blasting industry to promulgate a standard of care so a judge can feel confident that blasting can be routinely and systematically controlled and if the legal standard is changed from strict liability to negligence a subsequent judge or jury will be able to evaluate the level of care exercised by the blaster. This paper also suggests that the industry and/or ISEE develop and disseminate a comprehensive standard of care that courts can use to further justify a change from strict liability to negligence and evaluate the standard of care.

Jan 1, 2003

By R. Singh, M. Roy, D. Singh

Success of a blasting pattern in Blasting-off-the-solid (BOS) in Bord (Room) & Pillar method of coal mining is judged by the percentage of pull achieved vis-à-vis the yield of coal produced in a blasted round. Improper blast design and distribution of explosives in shot holes normally causes poor breakage i.e. a major portion of shot holes left unbroken resulting into reduced yield per blast. Over and above the disturbance to the roof is also due to excessive vibration caused by explosive energy not properly utilized in fragmentation.

Jan 1, 2003

By Suresh Menon

The explosive industry in India has passed through various stages - from a period of total dependency to a period of self sufficiency and now, is saddled with large spare capacity. The last decade and a half saw the emergence of small scale manufacturers, which until then was thriving on International technology.

Jan 1, 1998

By Paul Sterk

In underground mining a great deal of time, money, effort, and resources have been used in the effort to minimize blast-induced damage. This damage occurs to the back, ribs, and pillars when the energy of the explosive is released back into the rock due to over confinement or the overloading of explosives in the perimeter holes. This damage can result in roof falls, dilution of ore, excessive rock bolting, scaling, screening, shot-creteing and other safety and support issues.

Jan 1, 2003

This paper will review some of the work conducted in the past at the Dynamic Effects Laboratory to examine the use of stress waves and fracture mechanics in understanding dynamic fracture and fragmentation in blasting applications. Along the way, we will use photoelasticity and high speed photography to better understand the mechanisms of fracture and fragmentation.

Jan 1, 2015

By Jack Eloranta

Optimization of blasting requires the comprehension of processes including drilling through milling. The author has previously considered the role of powder factor in relationship to downstream processing costs. Recent modeling done by Lownds provides improved prediction of fragmentation based on the distribution and level of blast energy. Many recent studies have indicated improved downstream costs due to higher powder factor. However, changes in powder factor are accompanied by changes in pattern. The purpose is to segregate the effects of higher powder factor from powder distribution. This paper will attempt to use typical Mesabi Range iron ore parameters and costs to illuminate the subject of total process optimization.

Jan 1, 2001

By R W. Thomas

"This paper explores the possibilities of generating radical improvements in the drihing costs andproductivity of blastholes through the efforts of integrated teams as opposed to traditionalcustomer/vendor relationships."

Jan 1, 1996

By Douglas A. Anderson

The US Bureau of Mines, in RI 8507, has shown that blast vibrations at low frequency are more likely to cause damage and complaints than those at higher frequency. Since that publication in 1980, the Office of Surface Mining and many state and local regulatory authorities have incorporated frequency in their regulations for acceptable ground vibration from blasting. Even when frequency is not explicitly stated in regulations, it may become an issue in hearings or in court.

Jan 1, 1992

By W. J. Birch, M. Kirke

Despite increasing competition from mechanical methods of tunnelling, the drill and blast method is often still the most viable method of excavating tunnels in strong and abrasive rock. To advance a tunnel using drill and blast, explosives are loaded into boreholes in the rock and detonated according to a prearranged sequence. On detonation of the explosive, the rock is fractured and displaced from its original position, leaving behind the desired void. Among the secondary effects of a tunnel blast are ground vibrations caused by elastic disturbances that propagate away from the blasted tunnel face. The possibility that such ground vibrations may cause permanent damage to property and substantial nuisance has generated significant opposition to the use of drill and blast, particularly in urban areas. It is therefore essential that the blasting engineer is able to predict Peak Particle Velocity (PPV) vibration levels at locations in the vicinity of the blast site. Such predictive capability enables the engineer to design blasts so as to ensure that ground vibrations can be kept within acceptable levels. The objective of this project was to analyse data obtained from the ground vibration monitoring program undertaken during the drill and blast excavation of a hard rock tunnel in Central England. Seismograph recordings of tunnel blasts contain a vast amount of information that cannot possibly be expressed using a single PPV value. The main focus of the study was to investigate whether predictive capability could be improved by using scaled distance models derived for selected PPV components relating to specific detonator timings in a given tunnel round. This study has established a method of analysis that can unlock this information for predictive purposes. By permitting the extraction of sub-event Peak Particle Velocity (PPV) values and allowing Scaled Distance (SD) models to be derived for individual period numbers or groups of period numbers, the method has the potential to vastly improve PPV prediction from tunnel blasting. The method established could also help diagnose blasting problems and help target blast design modifications, resulting in improved efficiency and excavation rates.

Jan 1, 2005

By Jerald E. Harris

"Often taken for granted, drill accuracy plays a major role in the relative success or failure of a blast.Expensive technological advances in equipment capabilities, drilling tools, communications, explosives, and timing can quickly be nullified by poor drilling."

Jan 1, 1999

By Russell D. Melton, Gary A. Kanelos

A construction company performed blasting operations to break up limestone bedrock for excavation of residential basements. The owners of an existing residence located approximately 400 feet from the operation claimed that vibration damaged the structure and created foundation subsidence by lowering the moisture content of the foundation soils.

Jan 1, 1996