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By Emmett J. Ientilucci, Martin Held, Xuesong Liu

Mining is crucial for advancing technology and science by providing essential resources and materials. Quarry blasting, a necessary process in mining, releases these resources and chemicals, driving research and engineering improvements. However, NOx (nitrogen oxides) is an undesired contaminant produced during quarry blasts, posing a significant negative impact on mining activities. Therefore, detecting and quantifying NOx emissions is essential for designing effective blasts, analyzing their dynamics, and reducing contaminant production. Image processing and machine learning, including deep learning methods, have been applied to solve smoke plume detection and segmentation tasks. Most research has focused on smoke from campfires or forest fires, which are important for early fire and smoke detection. However, there is limited research on quarry blast smoke using machine learning methods, which presents challenges for recognizing the smoke plume from complex background scenarios and objects, including collapsed rocks, scattered soil dust and dirt, and the dynamic movement of the scene due to blast vibrations. Detecting NOx within the smoke plumes is further challenging because NOx must be distinguished from the overall smoke plume, as they share many common spatial features. To resolve this issue, we propose an ensemble method for NOx detection that combines smoke plume segmentation with NOx fume detection. First, we apply a smoke plume segmentation model to identify the smoke plume regions. Then, we use these masked-out smoke plume regions to detect NOx based on its unique color features. The first stage of the ensemble method helps block out complicated confusers in the background, such as reddish and brownish dirt. Next, we specifically design a color classifier for NOx to further improve its sensitivity. We evaluate the overall video-wise performance using accuracy, false alarm, and miss rates based on sampled image frames from videos. Additionally, we assess the mean Intersection over Union (mIoU) for smoke plume segmentation and the mean Average Precision (mAP) for image-wise performance from an algorithmic perspective. In summary, this paper represents the first attempt to apply machine learning approaches to NOx detection in a memory-efficient and time-efficient manner.

Jan 21, 2025

By Conny Postnpaok, Mark E. Hammele

"A major problem that has continued to plague the surface oil industry is blast induced damage to the coal seam. Atlas Powder Company has addressed this situation through several years of field research in full-scale production environments. Many operations across the United States havebeen evaluated ."

Jan 1, 1989

By Ian Tolliday

Emulsion Explosives manufacturers are aware of the destabilizing effect that the presence of inorganic impurities such as magnesium and iron and organic impurities such as naphthalene sulfonates and alkyl amines can have on their emulsions. This destabilization often manifests itself as severe crystallization and subsequent product loss. This paper describes the performance testing of specifically developed emulsifiers which give greatly improved emulsion stability in the presence of high levels of impurities. The test work involved a series of stability tests using ammonium nitrate doped with various levels of crystal modifier and anti-caking agent. A further series of tests were done to evaluate the stability using ammonium nitrate doped with various levels of iron and magnesium ions.

Jan 1, 2018

By S K. Mandal, S Dasgupta

"Damage is classifi ed as loss in the integrity or deterioration in the quality of rock massand is infl uenced by methodology of excavation on the geo-technical properties of rockmass. Overbreak, on the other hand, is the result of damage and is quantifi ed in either of the terms viz., extra mucking, shot-creting, application of extra support system and extension of scheduled completion time. Damage or overbreak in rock mass by the impact of blasting, is generally unavoidable but, the magnitude can be minimized so that it does not deteriorate the quality or integrity of structure. The paper, here, analyses magnitude of overbreak of a powerhouse cavern with respect to different blast patterns implemented at the site. The magnitude of overbreak was analyzed in terms of profi le measurement with the help of laser profi ler and percentage of halfcast markings observed on the periphery rock wall. The paper revealed the impact of decoupling ratio, blast pattern and geometry of blasting patch on the magnitude of overbreak. The authors observed that presence of un-favourable joint pattern or foliation plane along the periphery rock wall couldn’t contain magnitude of overbreak within allowable limit. The analyses revealed that percentage of half-cast markings on periphery rock wall was infl uenced by response of rock towards detonation of explosive and cannot be a single parameter to assess the effectiveness of a blast. The analyses also revealed that magnitude of overbreak for down-stream wall was more than that observed in up-stream wall."

Jan 1, 2008

By Piyush Rai

Proper use of fi ring pattern vis-à-vis the blast requirements can provide optimal blast performance in terms of fragmentation. Further to this, each fi ring pattern has its own characteristic, for instance, although V-type and diagonal fi ring pattern provide same Se/Be ratio, the V-type fi ring pattern increases the opportunity for in-fl ight collision amongst broken rock fragments during their movement. Similarly straight V-type and skewed V type fi ring patterns (V1,V2 etc.) have their own characteristic strengths and weaknesses. In this light the present paper highlights the application of three different types of fi ring pattern on two different type of sandstone overburden benches of a large coalmine in India. The study reveals that Firing pattern infl uences the effective spacing to burden ratio at the time of detonation. By changing the fi ring pattern, effective burden (Be) changes and the ratio of effective spacing (Se) to effective burden (Be) during the fi ring is also subject to change in comparison to drilled spacing to burden ratio (S/B) Hence, the Se/Be ratio vis-à-vis fi ring pattern must be used to design the blast rounds. The results have been derived on the digital image analysis based fragment size characterization, excavator performance and evaluation of powder factor values on blasted muck piles. Skewed V- type fi ring yielded the best results in comparison to straight v-type and normally practiced diagonal fi ring pattern on the moderately strong sandstone benches, whereas, the existing diagonal fi ring pattern appears to be satisfactory on weak (weathered and gritty) sandstone benches. The presence of geological anomalies has also been investigated.

Jan 1, 2008

By Courtney Vallejo, Rafiqul Tarefder

This study examines the effects of small scale airblast experiments on cohesive soils and the resulting ground vibrations and crater geometries. Relationships for ground vibration attenuation with soil depth and distance from the blast source were developed. The study is part of a broader research topic of understanding the vulnerability of earthen embankment dams to blast loading. Many earthen embankment dams in the United States were constructed more than fifty years ago and were not designed to withstand high-stress loading such as blast loading. These structures may be susceptible to failure and it is important to describe the response of the earthen dam during a blast event.

Jan 1, 2013

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 Cristian Rodriquez, Fernando Fernandez, Rodrigo Fuentealba, Tom BoBo, Maria Rocha, John Kemeny

This paper describes a case study that was conducted at a new mine in South America. This mine has significant geologic variations that will result in different distributions of hard and soft ore being mined at different periods of time over the mine life. A study was conducted to determine the optimum blast design that will meet the mill throughput requirement of 95,000 tonnes (104,720 tons) per day for the first 10 years of the mine life. As part of this study, field rock mass characterization and laboratory tests were conducted. This includes standard rock mechanics tests as well as rock breakage tests used in mill simulations. The geology of the ore body was broken up into four Geologic Units, and statistical variations in the properties were determined for each unit. Using this data along with the data on the occurrence of the different geologic units over time, simulations were made of the run-of-mine (ROM) fragmentation due to different blast designs, and these results were used in simulating the resulting throughput after crushing and grinding. Four blast designs were considered with powder factors of 0.44, 0.54, 0.64 and 0.94 kg/t. The results of this study show that determining the proper blast design is important in ensuring that the mill throughput requirement will be met over the mine life.

Jan 1, 2015

By R. Franfield, W. J. Birch, L. Bermingham

Previous researchers have put forward two different theories as to the origin of air overpressure from quarry blasting. In 1980, Siskind et al postulated that the initial face movement gave rise to the displacement of air and that this resulted in the air overpressure pulse. However in 1990 McKenzie et al carried out research that indicated that the air overpressure pulse came into being as consequence of the shock wave created by the detention of the explosive charge in a blast hole, rapidly propagating through the rock and then impacting on the quarry face.

Jan 1, 2013

By Greg Wyartt

Although electronic detonators and blast initiation systems have been commercially available for several decades, uptake in the Australian mining industry has been very slow when compared to other global mining regions. The safety and operational advantages of electronic initiation are generally well understood in Australia, however there has been a prevailing perception that these advantages do not outweigh the extra financial and technical investments.

Jan 1, 2019

By Charles H. Dowding, Catherine T. Aimone

Rock particle sizes were measured at fourteen steep-slope Appalachian coal mines during production blasting. The distribution of rock sizes shows the effects of inter-hole timing, sequence of hole initiation, as well as charge distribution within each shot. Blast design parameters were selected to: (1) minimize displacement of broken rock conforming to throw control required of mining methods, (2) minimize seismic effects, and (3) create breakage at a cost economical to mining operations.

Jan 1, 1983

By Carlos Pañura, Michael Geldres, Alejandro Rojas

In this current era of production in large volumes of surface mining, which demands the realization of large-scale blasting, the mining industry must deal with the impact of the vibrations generated by the detonations that are carried out daily in the mines. In this context, the need arises to minimize and control the impact produced by vibrations by determining the interference times of each generated vibration waveform. The vibration waves are produced by the detonation of the explosive charges of each blasthole, analyzing the vibration waves produced by each blasthole, allow us to determine the optimal time between the detonation of each blasthole to reduce the vibrations of the production shot. Once the optimal time is found, it is possible also, to predict the vibration of the production shot (considering times and sequences) using predictive models. The waveform recorded includes information regarding the particle velocity and the dominant frequencies of the vibration. To determine the time between holes, a graph was constructed with the values of the vector Sum VPP (m / s) vs Time between blastholes (s), once the time between blastholes “t” was found, the simulation of the output sequences continued in such a way that, by adding the single waves generated by the blasthole, it gave us a record of vibrations with the lowest level of vibrations.

By Bill Paysse, Lyle Ruffle

My intention is to produce a video, pictorial, and oral presentation on utility blasting, primarily power pole holes and ditches. Included will be blasting for a take-off structure inside of Wanapum substation, jointly owned by BPA, PSE, and Seattle City Light, and blasting for 230kV steel tower foundations.

Jan 1, 2007

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 Charles Zdazinsky

Back-break induced from blasting is a concern in open pit metal mining because it compromises the conditions of the pit’s final walls. Final walls that have excessive blast induced damage commonly require extra attention and can often lead to increased cycle times. Most importantly however, the safety conditions of a back-broken region can be significantly compromised and it must be addressed to prevent injury and/or damage to equipment. This occasionally results in the necessity to alter mine plans to prevent an incident from occurring in a back-broken region which can be costly to the mine.

Jan 1, 2014

By Trevor Ames

Highwall instability, and sometimes referred to as ground failures, historically are a consistent contributor of mine injuries and fatalities within surface mines. To combat this several efforts, including those from NIOSH (CDC), to educate the mining community with insightful literature focused on hazard recognition and advances in ground monitoring systems have been performed. The question is can more be done or is this our last line of defense to manage potential dangers? Is there a more effective method to reduce hazards presented by ground failures including rockfalls?

Jan 1, 2015

By Michael Louis, Charles Dowding

Concern over construction vibration-induced cracking has led to development of a new approach to vibration monitoring called autonomous crack measurement (ACM) and illustrated in Figure 1. This paper describes the concept as well as sensor performance in the first test house fitted an ACM system. Response of three cracks in this concrete masonry unit (CMU) house was measured as part of the system verification. ACM employs a single sensor that measures both weather-induced micrometer changes in crack width and those produced by habitation and ground motioninduced vibration. This comparison is displayed in real time via the Internet without human interaction. Graphic display through the Internet provides a new pathway for communication with the public. Such visual comparison of changes in crack width provides a simple alternative to the present system of comparison of measured and allowable vibration time histories. Measurements reported herein show that weatherinduced response of cracks is greater than that caused by presently allowable construction-induced vibration.

Jan 1, 2003

By Lon Santis

This paper describes several applications of quantitative risk assessment in the management of commercial explosives operations. The Institute of Makers of Explosives’ (IME) quantitative risk assessment software modeling program IMESAFR was used for this analysis. Modeled activities include the unloading of a ship at port, locating a safe haven, and dealing with encroachment on a manufacturing facility. The layout of actual explosives sites were used for the analysis. The risk of fatality is analyzed and shown it can be used to make informed operational decisions for each activity. A study of the risks to individuals from activities involving commercial explosives compared to individual risks from other daily activities or exposures is also presented.

Jan 1, 2008

By J. Meissner

In this paper vibratory crack response is compared to that produced by volumetric changes in foundation soils induced by natural events. These natural phenomena include changes in the water table, changes in soil moisture, and formation of ice lenses to name a few. Previous papers have compared vibratory responses of cracks to atmospheric effects such as those produced by the passage of weather fronts and daily changes in temperature and humidity. Periodicity of these atmospheric effects is on the order of a day to half a dozen days. Thus it is possible to observe atmospheric effects with measurement over a period of weeks to several months. On the other hand, crack response produced by volumetric changes in foundation soils occurs over a period of many months and/or may be seasonal in nature if not longer in the case of drought. Thus its measurement requires long periods of observation (many months to significant fractions of a year) or observation during critical seasons. Since it occurs over long periods of time, its observation may be obscured by climatologically induced crack response. These soil volume changes are compared with climatic data to describe the correlative nature of crack response in time with the soil volume change phenomena and likely climatic causes.

Jan 1, 2009

By Alan Bauer

During the past several years, the trend to large-diameter blastholes in both open pits and underground mines along with the continuing developments in slurried explosives and delay systems has kept things exciting for the drilling and blasting engineer. This has been particularly so in underground mining, where new mining systems having lower cost and higher productivity have emerged. Crater technology has produced new large-scale methods for resisting front penetration in tar sand mining and also new underground retreat mining methods and methods of raising.

Jan 1, 1978