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By L D. Lawrence

Certain blasting applications are more prone to the generation of significant levels of nitrogen dioxide post blast fumes, more commonly referred to as after blast smoke, generally ranging in color from dark yellow to bright red. This paper reviews basic background chemistry defining the observed fumes and attempts to correlate geology, blast design, and explosive composition effects on the level of nitrogen dioxide that can be observed in various blasting conditions. Additionally, a test setting for evaluating the generation of post blast fumes is presented with pertinent test data detailing generic explosive formulation modifications which effect the overall level of post detonation generation of nitrogen dioxide.

Jan 1, 1996

By Fumihiko Sumiya, Kunihisa Katsuyama, Yuji Ogata, Yuji Wada, Yukio Katoh, Yoshikazu Hirosaki

In our previous work, the results of photographic observation using a high speed framing camera showed that the difference between precursor air shock wave velocity and detonation velocity was primary factor for the channel effect. It is assumed that the decreasing precursor air shock wave velocity can prevent the channel effect in charge hole.

Jan 1, 1996

By Thomas E. Brown

Commercd explosives have evolved through this century f?om dynamite through ANFO to the current lines of Water Gels and Emulsions. Water Gels and Emulsions evolved to counter the lack of water resistance and density of ANFO yet maintain its low cost position verses dynamite. Today, explosives must be safe and inexpensive and perform under a wide range of temperatures, function efficiently in wet or dry boreholes and have a good shelf life. Emulsions meet this criterion, which is why they are the current trend products worldwide.

Jan 1, 1998

By Ron Woolf, Corry Goumans

This paper describes rock slope remediation performed along America’s first Superhighway, the Pennsylvania Turnpike and in particular, the specialized drilling equipment designed and built by Pacific Blasting to complete this work. This S-month project was performed on an existing rock cut slope within the Bedford Narrows, a gap formed by the Juniata River through Evitts Mountain. These rocks are in the folded Juniata and Tuscarora Formations within the Valley and Ridge Province and strike northeast with near vertical to slightly overturned bedding.

Jan 1, 2001

By Martti Hagfors

UNDERWATER EXPLOSIONS - Part 6 - EFFCTS OF CYLINDERICAL SHAPE OF CHARGE TO THE RESULTS OF ENERGY MEASUREMENTS OF EXPLOSIVES

Jan 1, 2008

By Dale Ramsey

As someone who has enjoyed photography as a hobby for many years, aerial photography to me has always been an exciting way to give a different perspective to my images. Our industry is always in search of new technology for bet­ter and more cost effective methods to improve our trade and aerial photography is a great tool to improve project planning or document its progress. It has typically involved conventional aircraft both fixed wing and helicopters but neither method is always available or cost effective. The lat­est innovation since digital imaging is the development of Unmanned Aerial Vehicles (UAVs) or drones. But there is a lot of uncertainty with this amazing new technology’s fu­ture in the U.S. as the Federal Aviation Administration (FAA) is under review and development of UAV regulations for commercial use which are slated to be completed in 2015.

Jan 1, 2015

By Langdon T. Mitchell, Karl Ingmarsson

The title is not referring to jewelry; nor is it about diamond core drilling. This article is instead about an emerging application for diamonds, hard rock percussive drilling with diamond drill bits. Diamond’s outstanding wear resistance has long been taken advantage of in core drilling. However, until now diamond has been less successful in hard rock production drilling in the mining and quarry industry.

Jan 1, 1999

By Brian Stump, D. Craig Pearson

This work quantifies seismic coupling as a function of charge weight for single-fired (simultaneously detonated) explosions observed in the mine and at regional distances. These single-fired explosions are contrasted to standard production shots from the same mine. Production shots include cast blasts to remove overburden and coal shots for fragmentation. The blasts were conducted in a mine in NE Wyoming. The data sets consist of measurements in the mine (100-10,000 m) and at regional distance (360 km) using a seismic array near Pinedale, Wyoming (PDAR). The single-fired explosions ranged in designed size from 5,500 to 50,000 lbs. Peak amplitudes measured at a single element of the regional array are modeled by a power law relation dependent on explosive weight. Scaling constants were determined for each of the dominant regional phases: b(Pn) = 0.84±0.14; b(Pg) = 0.84±0.09; b(Lg) = 0.91±.08. Spectral ratios of observations from different explosions observed at the same station illustrate the frequency dependnce of the source scaling relations. Spectral ratios of in-mine observations are consistent with those of regional data. The observed single-fired ratios are well replicated by Mueller-Murphy source model ratios. The data and model illustrate both the increase in long-period spectral level and the accompanying decrease in source corner frequency with increasing charge weight. The coal and cast blasts that make up the production shots ranged in size from 77,000 to 4,738,230 lbs. The peak amplitude (1-20 Hz) for the largest delay-fired production shot (4,738,230 lbs.) is comparable to that of the largest single-fired explosion (50,000 lbs.). This comparison can be explained in terms of destructive interference between waveforms from individual boreholes introduced by delay firing. Shot specific models of delay firing suggest that peak amplitudes in this same frequency band for the production shots are insensitive to the total amount of explosives in the blast. Peak amplitude data at regional distances supports his modeling result.

Jan 1, 2002

By S Lukovic, Vishwa Bhushan, Calvin J. Konya

Effect of each of these variables has been well characterized for ANFO. This paper presents results of underwater energy measurements for one watergel and one emulsion type of slurry explosive which were initiated by 3 types of initiators (one electric and two cords of different strength) in 2 and 3 inch diameter steel pipes. Results of this 2 x 3 x 2 factorial experiment show the effects of detonating cord on energy released by the watergel and the emulsion explosive. Effect of diameter and its interaction with cord strength have also been characterized for the two explosives.

Jan 1, 1986

By Andrew Wetherelt

Blast vibrations are of paramount importance in a society where ever increasing development is putting more stringent requirements on their control. Increasing civil development and more complex extraction scenarios make the trade off between proficient vibration control and productivity difficult to ascertain. Historically, reduction of induced vibrations levels was achieved through a reduction of MIC’s leading to smaller but more frequent blasts in order to meet extraction targets.

Jan 1, 2007

By Jiang Han, J. F. Shao

Based on the rock blasting engineering, The Self-Organizing Map (SOM) network has been implemented for the concept and method of rock blastability classification. The Self-Organizing Map (SOM) is a neural network algorithm which is especially suitable for the analysis and visualization of high-dimensional data. It maps nonlinear statistical relationships between high-dimensional input data into simple geometric relationships, usually on a two-dimensional grid. The mapping roughly preserves the most important topological and metric relationships of the original data elements and, thus, inherently clusters the data. SOM allows easy data fusion enabling visualization and analysis of large databases of rock blasting engineering. As a case study, the classification technique based on SOM has been used to classify the rock mass blastability rank. It can be founded from this paper that the SOM networks can be developed well based on a comprehensive data set of rock blasting engineering.

Jan 1, 2002

By Constanza Bujes, Mark Jones, Graham Crook, Yansan Jamyanbaatar, Sedat Esen

Tracking ore characteristics such as grade and hardness from its original position into the material handling and processing stages remains one of the key challenges in open pit mining of hard rock deposits. The most efficient technique for rock fragmentation and separation of ore from waste is blasting, which induces changes in the grade distribution by displacing the in-situ ore into a diggable muck pile. Material movement defines the post-blast grade distribution, which is key to optimising the value of the ore and accounting for ore loss and dilution. Techniques to directly measure the displacement in open pit mining have been implemented routinely and have provided calibration and validation data for blast models to build upon. The JK Value-Based Ore Control blast movement model (JKVBOC) is the latest development of a series of research studies into blast movement and ore control at the Sustainable Minerals Institute of the University of Queensland. The blast model discretises the bench into blocks, defines the initial velocity of each block based on the blast design, confinement and explosive properties, and simulates the displacement using a physics engine. Calibration and validation of the model has been performed in open pit hard rock mines in Australasia in diverse confinement conditions. This paper describes the calibration and validation of the blast movement model against direct measurements of blast movement and final muck pile shape for a case study where the displacement of multiple shots was modelled for an open pit mine, with an analysis of the implications for ore loss and dilution. A key finding in this study is the need for further integration of this technology into the existing systems for ore control, and the potential for applications in tracking ore characteristics other than grade into process control.

By Adrian Moore, Alan Richards

A real-time system for prediction of the effect of meteorological conditions on airblast overpressure levels has been established in the Hunter Valley Coalfield in Australia. Real-time meteorological data from continuously operating sounding equipment and a predictive meteorological model is input to an atmospheric refraction model that enables the effect of meteorology on airblast overpressure levels in the area surrounding the blast site to be evaluated. Graphical outputs from the model, which are superimposed over a scaled airphoto of the mine and surrounding area, show the extent that airblast levels will be increased. When combined with inputs that quantify the effect of blasting specifications, the airblast levels that will result in the surrounding area from the combined effect of blasting specifications is determined. The model permits those responsible for blasting to make more accurate decisions on suitable times that blasting may take place to conform with applicable airblast limits.

Jan 1, 2009

By Paulo Couceiro, Manuel Lopez Cano, Carlos Rodgriguez Calvo

Apart from its difficult execution, underwater blasting is one of the most critical operations of the blasting techniques; mainly because of the ground vibrations - normally associated with low frequencies -, destructive hydraulic shock waves, the difficult coordination, and high costs. To solve these challenges during the underwater blasting on the expansion program for the Panama Canal “Widening and Deepening of the Pacific Entrance and the South approach Channel to the Third set of Locks of the Panama Canal”, a new method to blast using bulk explosive, developed by MAXAM, was used. The project was successfully executed, and more than 800.000m3 were blasted in less than 5 months, jointly with the biggest underwater drilling platform ever build, the Yuan Dong 007, with ten hydraulic drills on board guaranteeing a high production, excellent fragmentation result, total control of the vibration levels, no complain of the neighborhood surrounding the area of the project and simple local logistic due to the classification of the main product used (an oxidizer classified as 5.1). That was finally sensitized down in the hole.

Jan 1, 2011

In situ, most Taconite is heavily pre-fractured; because of the high cost of comminution of taconite, maximum fracture of pre-existing blocks is desirable. Sustained borehole pressure plays a significant role in fragmentation, especially by penetrating pre-existing fractures. The distribution of explosive-induced energy in the burden in three dimensions was calculated. Data on the comminution of single particles was used, with the distribution of energies and the distribution of pre-existing block sizes, to calculate fragmentation for a case study. The calculation agreed well with the measured fragmentation. Sequential comminution events are much more efficient than single ones, and enhanced fragmentation may be possible with alternative blasting practices. Some important factors in the dependence of comminution on energy input are discussed.

Jan 1, 1995

By Dyno Nobel

Impact of Enhanced Security on Operations Budgeting - What is the “value” I receive for enhanced security? Is there a “return” for the money I spend? Regulatory driven Economic driven

Jan 1, 2006

By Evan Smart, Andrew Palangio, David Klingspor, Blessing Taiwo

This study presents a DMAIC-based approach to optimize blasting performance and achieve crusher-compatible fragmentation at the Walker-Severn Quarry in Ontario, Canada. By applying the Six Sigma DMAIC (Define, Measure, Analyze, Improve, Control) framework, the study aims to enhance the integration between blasting and primary crushing operations. Several representative blasts will be simulated and evaluated using both aerial and terrestrial image analysis technologies to assess fragmentation characteristics. The investigation was guided by quarry-specific Key Performance Indicators (KPIs), ensuring that blast design modifications were both practical and operationally relevant. Through structured analysis and data-driven refinement of blast parameters, the study reveals how this framework was used to address the quarry production demand for increased crusher throughput, and reduced processing costs. The existing quarry blast design was assessed as a baseline and compared against the crusher's inlet requirements and the acceptable fines level specified by the quarry. This evaluation aimed to identify and implement modifications to enhance blast performance. A drone (UAV) was employed to capture post-blast images and monitor blast pile displacement. These UAV images were used to generate an orthomosaic image, which was analyzed to assess fragmentation. The orthomosaic was overlaid onto a GIS platform using a 10m-by-10m grid to evaluate fragmentation distribution across the bench and identify areas requiring optimization. Additionally, drone imagery was utilized to monitor the impact of each blast on the subsequent blast's free face and to assess energy utilization for optimizing front-row holes to achieve improved fragmentation. The outcomes of this research offer a replicable methodology for continuous improvement in quarry blasting practices, with a focus on producing fragmentation that aligns with primary crusher requirements.

Jan 26, 2026

By Catherine T. Aimone-Martin, Elena Oana Jacobs, Brent Meins

Accurate pressure measurements during underwater detonations are critical for the protection of structures and mitigating impacts to fish and marine mammals. Current guidelines that limit underwater pressures are based on past studies, many of which used sample rates of 48 and 65 kS/s (48,000 and 65,000 samples per second). These sample rates may be insufficient to accurately record high frequency, sharp rise time blast pressures. As such, pressure thresholds associated with fish and marine mammal injury or mortality may be underestimated, calling into question the pressure and sound pressure level guidelines that govern underwater blasting today.

Jan 1, 2019

By Reinhold Daykin, Piers Wendlandt, Nathan Rouse

Drilling and blasting are key components of every hard-rock (i.e., metal/nonmetal/coal) mining operation. Well-executed and maintained drilling and blasting can have a major positive impact on the overall success of such operations. This case study presents the implementation of a new drill and blast engineer position and systematic improvement of the drill and blast operations at a surface metal mine.

Feb 1, 2020

By Kwang-Yeom Kim, Dong-Gyou Kim, Hyo-Kwan Yoon

This study was intended to simulate the blasting model using notched-hole with numerical approach. Numerical analysis approach was applied to compare and evaluate the blasting model using notched-hole and circular hole. To implement non-linear dynamic blasting model, blasting analysis was carried out with AUTODYN code. Behavior of two models was compared and evaluated using AUTODYN and visual analysis and quantitative evaluation based on pressure and stress to verify the effect to induce the destruction territory to the specific direction when blasting with notched hole was attempted.

Jan 1, 2010