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By C M. Deosthale, V N. Pangal, M N. Rao

New Mangalore Port is the most important port in Karnataka State, on the west coast of India on Arabian Sea. It handles export of iron ore, granite, coffee, spices etc and imports of crude oil, fertilizers etc. Since 1991, after economic liberalisation by the Government of India, the exports and imports at this port got a boost. Hence the Port Trust felt the need to increase the draught by about 3 to 5 meters for access to bigger ships. In response to a global tender in 1995, the Dutch Dredging Company got the contract to remove 30,000 cu.m of hard granite bed rock, covering 28,000 sq.mtr. area for the Turning Circle and oil Jetty. The operations of drilling, blasting and dredging were to be carried out to deepen the area to about 15 m draught without affecting the normal trade at the Port. This was a time bound contract to avoid interruption by severe Monsoon rains.

Jan 1, 1999

By Cathy Aimone-Martin

The City of Henderson, Nevada is experiencing extraordinary population growth. Some residential development requires blasting to be conducted at close proximities to high-value houses. Blastingrelated concerns voiced by the community residents include dust, noise, fears of damage to residences, and claims of insufficient controls exercised by the blasters. Residents perceive geological conditions are adverse to the protection of structures at the current vibration regulatory limit of 0.5 in/s. Airblast limits are 120 dB. Vibrations felt within structures leave home owners with the perception that damage is taking place. New cracks appearing in homes at distances far from the blasting are being blamed on blasting.

Jan 1, 2007

By Trevor Garbutt, Peter Bellairs, Jason Sander, Glenn Shaw

The Yarrie Iron Ore mine is located in the Pilbara region of Western Australia some 200km eastsoutheast of Port Hedland, the closest large regional centre. The mine is owned by BHPIO who has contracted a large Australian mining contractor Roche Bros to be responsible for the total mining, crushing and trainloading functions. This paper describes a drill and blast optimisation program, resulting from the introduction of a new emulsion matrix called Titan@ Red used to manufacture both HANFO and pumped emulsion ANFO blends.

Jan 1, 1999

By Rene A. "Moose" Morin, Craig Copping

Innovative concepts in drilling and blast design have been used to remove deteriorated concrete and have enabled contractors to reduce costs and time on St. Lawrence Seaway rehabilitation projects. Time is of the essence on these contracts since the Seaway system is only available for this work during the winter freeze up. Unique electrical sequential initiation systems and specially modified drilling equipment have been used to accurately remove a narrow slice from the 83 foot high lock walls. These new methods successfully reduced demolition time, minimized overbreak and adhered to strict vibration limits.

Jan 1, 1986

By Charles H. Dowding

Public concern over blast-induced CRACKING has led to the search for a radically new approach to vibration control. The present system, while scientifically correct, is cumbersome to explain. Historically the potential for blast-induced cracking has come to be described through velocity time histories, which are correlated with observation of crack extension under controlled experimental conditions. Unfortunately time histories are simply too difficult for jurors and village or county regulatory boards to understand. Furthermore these arbiters must accept on faith that the observers were unbiased. Since these public bodies control the manner in which blasting activity is adjudicated and regulated, information must be presented in a form they can understand and that is not subject to second-guessing.

Jan 1, 1999

By Mike Higgins

"The purpose of mining and its related industries is the removal of, and usually the subsequentprocessing of, material from the earth. This includes mining for minerals, quarrying for stone, and civilexcavations. Where this involves rock, the most common method is to fragment the rock by blasting. "

Jan 1, 1997

By K. Ram Chandar, Vedala Rama Sastry

Fragmentation and muck pile profile together play an important role in optimizing the excavation costs for given geo-mining conditions. Initiation system is one of the vital parameters influencing the fragmentation and muck pile throw (profile). An attempt is made through this paper to study the characteristics of muck pile produced in addition to fragmentation. Two new parameters namely “throwburden ratio” and “muck pile ratio” are proposed for assessing fragmentation and movement of material. Field investigations were carried out in a limestone mine in southern India with shock tube and detonating cord initiation, using four initiation patterns, keeping other parameters like burden, spacing,delay timing etc. same.

Jan 1, 2008

By Thomas Palangio, Blessing Taiwo

Image-based fragmentation analysis is increasingly utilized in blasting operations to evaluate particle size distribution in a non-intrusive and efficient manner. However, the accuracy of optical granulometry systems can vary significantly with particle size. Higher precision is typically achieved for larger fragments, generally those greater than golf ball size when using drone-based orthomosaic analysis. In contrast, the detection and delineation of fine particles become less reliable due to constraints such as pixel resolution, particle overlap, and partial burial within the muck pile. This variability does not undermine the value of image analysis but rather highlights the need for a deeper understanding of its operational thresholds and the integration of complementary methods or calibration approaches to improve its reliability across the entire particle size distribution. Technologies such as WipFrag, originally developed in the 1980s, are designed to conduct in-situ fragmentation analysis within complex blast environments, where fines are often obscured by larger fragments. The challenge becomes more significant in blast rounds exhibiting wide gradation ranges and increased fines, particularly resulting from excessive energy concentration in high-pressure zones near the borehole. Previously, this issue was addressed through methods such as analytical correction, zoom-merge correction, and empirical calibration using Rosin-Rammler and Swebrec distribution models. However, these traditional empirical calibration approaches, particularly those tied to distribution functions like Rosin-Rammler have shown limitations, especially in accurately representing the fine region of the fragmentation curve. In contrast, the recently developed xP-fan model, which incorporates the relationship between powder factor and fragment size, introduces the fragmentation energy fan principle which Kuz-Ram model does not entail. This paper presents a study on the application of the novel xP-fan calibration to enhance the accuracy of optical granulometry systems. The findings demonstrate how xP-fan help calibrate the fine region of the PSD without deflecting the maximum size.

Jan 26, 2026

By Nickolas Vlahopoulos, Nicholas Stowe

A concept has been proposed for the focusing of underwater energy. An array of spherical TNT charges is used to achieve this aim. The goal of the present research effort is to model such a system and identify optional arrangement and detonation timing schemes. A fast-running model is necessary to perform optimization analysis due to the highly iterative nature of most optimization algorithms. This requirement renders the use of sophisticated numerical solvers impractical. An analytical, physics-based model must be developed to satisfy the demands of the multiple charge optimization problem. This model must capture shock propagation speed, pressure-time histories throughout the fluid domain, and multiple charge interaction phenomena. Such a model is presented herein.

Jan 1, 2012

By P. Ravanal, J. Blazquez, F. Ortega, P. Couceiro, J. Navarro

Massive blasting technique is an interesting alternative to optimize mining’s performance by enhancing digging rates and overall operation’s activities, especially when a reduced operational bench width is available. The exploitation of a huge bench through multiple blasts would mean a potential reduction in productivity and higher operational difficulties. In such hard circumstances, combined with complex geotechnical conditions, a full ground vibration analysis for near and far field vibrations are required in order to safely design and conduct the blast. In this paper, a comprehensive case study will be discussed to show how the application of massive blasting techniques was safely implemented in very complex geotechnical conditions. The proposed solution was based on performing a full ground vibration study to optimize blast design parameters, such as charging and timing, in order to fire the complete bench blast in a single shooting event, without compromising the slope stability. Thus, a massive blast with an approximate tonnage of 6.0Mt was successfully designed and blasted, attending all safety and stability criteria defined by the geotechnical and drilling and blasting departments of Minera Escondida.

Jan 1, 2024

Investigating blast vibrations typically utilises scaling and attenuation models for prediction of vibration amplitude over a range of charge weights and distances. A number of generalised relationships have been established from many years of far-field data analysis, where small changes in charge weight and ray-path distance are less critical. Under far-field conditions, small variations in local geology or geometry do not significantly affect the vibration scaling behaviour over an expected range of data. In the near to intermediate-field (less than 5 times the explosive charge length), small variations in wavepath and rock mass conditions between a blast and a monitoring point can greatly affect the outcome of vibration modelling. This case is especially true for underground blasting in sublevel open stoping, where the paths of blast-induced vibrations regularly encounter voids and preconditioned ground.

Jan 1, 2010

By K. Hausmann, P. A. Sashin, G. J. Prejean

Misfires caused by unreliable shock tube constructions can have significant cost implications and place field workers at serious risk during remediation. Ionomer materials, used as a subtube in shock tube constructions, provide superior hot tack strength, oil resistance, impact resistance at cold temperatures and excellent thermoformability properties. These are important features for resisting blast-throughs and ensuring blasting reliability in demanding environments, such as open pit mining in harsh environments. Superior hot tack strength, strain hardening, and excellent thermoformability properties of the ionomer materials ensure uniform powder distribution along the shock tube during construction and avoid undesired powder accumulation due to deformation or vibration during use. Oil or chemical resistance is another feature of Ionomers. This allows improved property retention in contact with oils and hence longer sleep times of the shock tube. Another feature of these highly engineered ionomers is superior impact strength at low temperatures. This plays an important role considering the resistance to fly rock impact in open pit mining operations in particular in cold climates.

Jan 1, 2011

By Italo Onederra, Gary Cavanough, Ewan Sellers

Reactivity of ammonium nitrate based explosives is associated with the presence of iron sulfides in the ground reacting with explosive products and in some instances causing spontaneous reactions which can lead to detonation. The stability of explosive products can also be linked to in-hole density, which influences detonation efficiency, breakage performance and the potential generation of Nitrogen Oxide (NOx) fumes. Reactive ground testing involves detecting a temperature rise of a mixture of a bulk explosive product sample, a ground rock sample and some specific chemical agents. This paper describes improvements in reactive ground testing involving the use of time lapse video analysis and detection of NOX gas emissions from the sample. Reactivity is stored and linked to a using cloud based software to map of the mine showing the exact location of the sample. The location marker can be selected to allow quick access to the sample test results and video. In addition to reactivity, the stability and detonation performance of bulk product can also be influenced by depth. In this paper, a system that simulates product at depth and measures density changes and monitors the structure of bulk samples is described. Results from an explosive product are analyzed and detonation performance is assessed by the measurement of velocity of detonation and detonation pressure.

Jan 1, 2018

By R D. Skaggs

A good blast is dependent on a well engineered design. However, a good design's performance depends on the control of the drilling and loading of the blast holes. The key stone to good blasting is the drilling of straight holes of the correct orientation in the required positions.

Jan 1, 1991

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 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

An explosive's velocity of detonation (VOD), can be used to indicate a number of important characteristics regarding the product's performance under specific field and test conditions. A number of new characteristic and transient VOD curves have been identified in the field, which can be used to evaluate explosive performance, control ground vibration amplitudes and frequencies, select the correct amount and type of stemming for use at the collar and in stem decks, eliminate explosive desensitization, evaluate primer performance, design air deck based blasts, evaluate contaminated explosives and to overcome post blast noxious fumes.

Jan 1, 1994

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 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