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By Jorge Cárdenas, Alejandro Luna

In mining simulation for fragmentation results prediction is of utmost importance to study feasibility, ensure safety, and estimate the correct use of resources in drilling an explosive to meet requirements and avoid excessive usage. One critical case is fragmentation prediction, developed through models. Developing a fragmentation model in a mining unit aims to control blasting results to align theoretical and real data and improve correlation. Therefore, it is essential to collect post-blast fragmentation data, organize it, and systematically process it to develop a suitable model that meets variable requirements. Using a robust system of equations, this model should generate the required results with minimal variability between simulation and actual results. Additionally, this model must be adaptive to reduce this variability. Studying the most known and used models in mining resulted in our work correlating Cunningham 2006, Swebrec, and CZM models. Thus, the Simfrag model was created, presenting a robust foundation and combining the most notable advantages of the aforementioned models.

Jan 21, 2025

By Joshua A. Bennett

"Lawsuits where owners allege their property has been damaged by nearby blasting routinely costblasting companies, explosives engineers, and others in the field both time and money. When ownersfeel the vibration of a blast, they immediately begin to look for damage and usually find cracking thatwas, in fact, present prior to the blasting occurring. When those owners begin to talk to their neighbors and legal counsel, blasting entities suddenly have multiple lawsuits being filed as a result of the same blast."

Jan 1, 2016

By Jackson R. Pressley, Bruce Vandenberg

The knowledge of how and when your explosives go off can help you make intelligent decisions regarding future application of explosives thus removing some of the black magic associated with blasting. The net result will be intelligently set-up shots with timing, explosive charges, and placement more accurately done. Lower operational costs can be achieved when the correct combinations are applied.

Jan 1, 1992

By Travis Davidsavor, David Provost

A segment of high-pressure steel petroleum pipeline needed to be replaced on a hillside and beneath a waterway within an existing right-of-way containing multiple petroleum pipelines. The pipeline replacement required excavation of sedimentary rock to allow placement of the new pipe. As a result of an existing right-of-way limitation, steep slopes, and hard rock, blasting would be required as close as 7.8 meters (25 feet) from two operating pipelines. Existing pipeline company standards would have effectively precluded the construction of the replacement pipe by blasting rock. To facilitate the required construction and evaluate actual pipe stress during blasting to ensure pipeline integrity, a comprehensive evaluation methodology was developed by a team of pipeline, mechanical, geotechnical, instrumentation, and blasting engineers. A total of 60 strain gages were affixed to the steel pipe and seismographs were buried at the surface near the blasting area. Test blasting allowed pipe stresses with corresponding ground motion to be monitored. A conservative analysis approach evaluated individual peak strains and revealed that only small pipeline strains, and therefore stresses, were induced in the pipeline as a result of blasting. This evaluation allowed specific procedures to be developed to inform the blasting operation of maximum explosive loading and minimum charge distances. Additionally, this effort provided the pipeline operator with appropriate pipeline operating pressures during blasting activities to limit total stresses in the pipeline to be below allowable stresses imposed by code, regulators, and company operational limitations. Recommendations were developed to measure the blast generated ground vibrations with seismographs buried at the depth of the pipe, near the pipe, and limit the ground vibrations from blasting to 150 mm/s (6 in/s). If ground vibration intensities of 120 mm/s (4 in/s) or more were observed, additional engineering review is recommended. Finally, all blasting would be suspended and all activities reviewed at peak ground vibration intensities of 230 mm/s (9 in/s). The evaluation effort resulted in effective and efficient construction of the pipeline replacement and allowed the pipeline operator to better understand blasting induced stresses on their assets.

By Zou Dingxiang

Rock blasting in the project of “Site Formation and Associated Infrastructure Works at Choi Wan Road and Jordan Valley” is the largest urban blasting project in the history of Hong Kong and also is rare in the world. More than 6.2 million of in-situ rock has to be excavated by blasting. The site is located in the center area of eastern Kowloon peninsula, surrounded by highways, registered cut slopes, high-rise residential buildings, MTR subways and the public utilities. The complex situations bring great difficulties and risks to the blasting works. A bird-view photo of the site is shown on Picture 1.

Jan 1, 2007

By Christoph Muller, Geoffrey Liggins, Mohan Hensman

Modern commercial blasting is as much a technical process as it is a business one. As with most processes both aspects of blasting are driven by and generate new data. The time-critical nature of commercial blasting in mining and construction projects, dictate the timely exchange of information so as not to impede production or commerce. Up-to-date information about the blast to be undertaken can help suppliers: meet customers’ expectations to address challenging ground conditions; react to a market where quickly changing orders occur regularly; and address as-drilled blast patterns as opposed to baseline plans. “Real-time” data exchange into and out of the blasting process supports the whole-of-mine data management that the industry is migrating to.

Jan 1, 2010

By Bobby Dupree

I remember a big problem with a seismograph in the winter two years ago. In response to a citizen’s complaint I placed a transducer near the corner of a two-story home. It was a pretty nice day for the winter months, the people were pleasant, and I had no problems digging a hole to place the transducer.

Jan 1, 2004

By Tom Snyder, John Brulia

Part 4 is the final article by the authors on hazardous materials (HM)transportation safety and compliance for U.S. shippers and carriers who offer and transport commercial explosives in commerce on public highways. This article covers hazardous materials (HM) cargo segregation and securement of non-bulk packaged explosives.

Jan 1, 2015

By Travis A. Davidsavor, David A. Provost

A segment of high-pressure steel petroleum pipeline needed to be replaced on a hillside and beneath a waterway within an existing right-of-way containing multiple petroleum pipelines. The pipeline replacement required excavation of sedimentary rock to allow placement of the new pipe. As a result of an existing right-of-way limitation, steep slopes, and hard rock, blasting would be required as close as 7.8 meters (25 feet) from two operating pipelines.

Feb 1, 2020

By Paulo José Costa Couceiro Junior, Manuel Lopez Cano

The biggest Port of Latin America - the Santos Port in São Paulo, Brazil - has been drilled and blasted by controlled underwater techniques in order to remove around 40,000 m3 (52,318 cubic yard) of rock divided in two outcrop rocks: Teffé and Itapema. Underwater pumped explosive, in combination with small cartridges areas, was successfully used in order to reach a target depth of -15m (-49 ft) and a width of 220m (722 ft) in the navigation channel. It was the first time that a pumped explosive was used in underwater blasting in Brazil and it represents a historic benchmark for projects of this kind in this country. The main challenges faced in this project include the control of the ground vibration, due to the necessity to carry out detonations 40m (131 ft) away from the quay wall - where the passenger terminal and the 80 year-old warehouse were located – and the rush schedule available, in order to finish the underwater drilling and blasting phase before the coming cruise season. Therefore, the perfect combination of an ideal pumped product with an effective pumping system has permitted to carry out the project in a record of less time than 3 months (against to the original expected time of 18 months), with all vibration events under control as result of the special ground vibration program carried out.

Jan 1, 2016

By Jorge Cárdenas Miranda, Hector Espinoza

Currently in open pit mining in Peru with double bench, it is a challenge to optimize fragmentation in the drill rows near to the slopes to ensure the performance in the loading and haulage operation along with the process in the plant. That is why the present paper addresses a previously unanalyzed variable on the effect of the discontinuity plane on the fragmentation results. From the numerical mathematical models applied through algorithms in advanced computational tools such as Elfen, it was quantified the improvement in fragmentation results as P80 through a correct pre-split plane both in its extension as well as in its width. The first results show an improvement of 30% in the P80 and ensuring the quality of the walls without damage to the matrix of the final wall. The basis developed in this paper is based on the concept of wave reflection in the free face zones where greater efforts are presented for fragmentation, a similar theory is presented in the variation of initiation sequences that seek a greater area of reflective planes in the form of "V". Cases were evaluated with a percentage of compliance of the pre-split planes from 0 to 100% evaluating the impact on the results and correlated with field information explaining the behavior and validating the benefit. From the quantification of the benefits, this work opens the possibility of focusing resources on optimizing the pre-split process to achieve an improvement in the fragmentation results, giving a greater tool in the decision to optimize the blasting process.

Feb 6, 2023

By Jason M. Ryan, T Michael LeBlanc, John H. Heiiig

Drill trajectory deviation is a recurring problem in the Mining Industry retreat stoping operations. As a result of this deviation, it is quite concevable that 60 kg (165 mm 0) and 103 kg (203 mm 0) explosive charges are detonated beyond the hanging wall contact. Consequently, there follows a reduction in hanging wall stability and an increase in ore dilution.

Jan 1, 1995

By Stuart Brashear, Robert Brush, Ben Cook

In early 1993, the Piney River quarry owned and operated by the Blue Ridge Stone Corporation of W W? Boxley received a series of complaints from the owners of a 130 year-old historic farmhouse that had been converted into a bed and breakfast establishment. Since the distance from the quarry to the farmhouse was substantial, a unique method of seismic data acquisition was utilized to determine if perceived blast effects were caused by air blast or low amplitude, low frequency ground vibration.

Jan 1, 1996

By Ayman Tawadrous

Cave mining offers a flexible technique to exploit large, low grade, deep ore bodies with low operating costs. It is typically done in either a top down approach; i.e. sublevel caving, or in a bottom up approach; i.e. block or panel caving, to extract ore bodies that may have been previously considered unfeasible to mine. Sublevel Cave (SLC) mining, in particular, is a cave mining method based upon the utilization of gravity of blasted ore while the overlying host rock fractures and caves under induced stresses and gravity. Thereby the caved waste originating from the overlying rock mass fills the temporary void created by ore extraction to achieve a controlled collapse of the roof.

Jan 1, 2015

By Alastair Torrance, George Boucher

The authors were involved in the Trial Blast work at Chek Lap Kok, the site of the new Hong Kong Airport. As part of that work a series of computer programs including 3x30, QFRAG, DESIGNER and 3DMUCK was employed to predict various aspects of the trial blast programme. These aspects included fragmentation and muckpiie shape. This provided an excellent opportunity for these programs to be calibrated, verified and compared under controlled conditions. The results indicated that computer simulation has reached a high level of sophistication and good correlation between prediction and measured results was found.

Jan 1, 1994

By L C. Taylor, H U. Lesiste

This paper describes a method for estimating the density distribution in the soil cap as a function of distance from its top at the time of impact with the target. It provides an estimate of the density distribution in the soil on the center line of the soil cap at the time of target impact for a single depth of burial of the charge and two heights of target and shows that, for the heights of target and the depth of burial considered, the thickness of the soil cap first increases from the in situ value and then decreases. The distribution of soil density along the centerline of the soil cap changes significantly with distance from its original position. These results can be used for validating hydro-code computations and the soil models used in the computations.

Jan 1, 2011

By Peter Duniam, Stephen John Brace

2000 HIGH-TECH SEMINAR Blasting Technology, Instrumentation and Explosives Applications Orlando,Florida,USA July24-27,200O. Objectives:- After completing this session 1. Explain safety issues 2. Do simple initiation design 3. Describe how the system works 4. Demonstrate scanning, hookup, testing and firing 5. Describe hot to do a post blast check 6. Explain how to treat misfired detonators

Jan 1, 2000

By Richard E. Danell

"There are a variety of approaches for wall control blasting in open pit mining operations. Safety forworking in the pit is the principal benefit. There are also a number of economic and productivitybenefits when appropriate techniques are used. The purpose and requirements of wall control blasting can vary quite significantly for different operations. When considering blast design, geology, geotechnical factors, drilling, explosives, economics and blasting history are all part of the engineering design process. In many operations, there is a high reliance on blasting history and economics for determining wall control blasting measures. This presentation outlines approaches that broaden the design process and discusses their advantages."

Jan 1, 1997

By Steve Dillingham

Whenever misfired holes or portions of misfired holes remain after a blast is fired, a hazardous situation exists until the unfired explosive materials have been disposed of properly. Yet, there are so many factors that can contribute to misfires that it is impossible to give blanket instructions on how to handle them. To complicate matters, misfires today are rare due to reliable blasting products. As such, it isn’t very surprising that many blasters have never had to deal with a misf i re condition. While the likelihood of a misfire occurrence is minimal, you should always be pre p a red to handle a misfire should you be involved in such an event. To begin, every blaster and blasting org a n i z a t i o n should develop a misfire policy which contains the company’s safe operating pro c e d u res, emergency contact list, as well as any regulatory compliance re q u i re m e n t s . Tailgate and/or company-wide safety meetings should communicate the company’s contingent misfire pro c ed u res and any special site-specific precautions BEFORE the start of any project.

Jan 1, 2004

By Kenneth Eltschlager

Business says that location is a primary component of being successful. So too is the importance of location in blasting. For blast seismograph data to be useful, the location of the blast and seismograph must be clearly documented. Another location of importance is that of a nearby structure. Establishing the spatial relationships between the blast, seismograph and nearby structures, allows the blaster to correctly interpret the data, evaluate the performance of the blast and gauge the validity of any complaints.

Jan 1, 2004