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By Jihan Farhan Lubis, Putu Chandra Darmansyah

Ground vibration caused by blasting has become a common concern, especially when blasting is conducted near buildings or structures. Uncontrolled vibrations can potentially damage nearby infrastructure if appropriate control measures are not implemented. PT Tambang Semen SUKABUMI, a limestone mining company, is planning to carry out blasting activities near a crusher building located approximately 80 meters away. This building is classified as a Class 5 structure, with a maximum allowable Peak Particle Velocity (PPV) of 40 mm/s, in accordance with the Indonesian national standard SNI 7571:2023. To ensure compliance with this limit, a Signature Holes Analysis (SHA) was conducted using the Hanwha HEBS II electronic detonator initiation system. This analysis measured ground vibration from single-hole blasts, with the average vibration from three SHA holes recorded at 49 mm/s. A site constant analysis using the scaled distance formula yielded a multiple R value of 0.87. However, the ANOVA table showed a significance-F value of 0.24, which is greater than 0.05 indicating that the regression model used for prediction was not statistically significant. Using the SHA data and assuming a maximum of 30 blast holes, a recommended delay timing of 22 × 15 milliseconds was selected. This produced a predicted PPV of 17.25 mm/s. The comparison between predicted and actual PPV values demonstrates that the delay configuration derived from Signature Hole Analysis provides reliable results. The observed deviations range from -16% to +29%, with an average deviation of only 8%, indicating a high level of accuracy and consistency. Using the actual blast data, three model prediction were applied for predicting the most accurate prediction that close to the actual value. The SHA method, utilizing actual single-hole vibration measurements and optimized delay timing, provided the lowest average deviation of ±8% and the smallest absolute error (2.45 mm/s) from actual measurements, demonstrating high reliability for sites with sufficient signature data. Meanwhile, the log-log regression model yielded the highest coefficient of determination (R² = 0.751) and the smallest prediction deviation (3%) when standard deviation margins were considered, making it highly effective for predictive modeling.

Jan 26, 2026

By Luiz Guilherme Isfer Maciel, Marilena Cardu, Fernando Golin, Jacopo Seccatore

"This study applies the concept of the difficulty of tunnelling by drilling an blasting (D&B) to selectedcases from the Brazilian tunnelling industry. The difficulty of tunnelling has been defined in previouswork as the difference of specific drilling (SD) from industrial average trend: easier when SD is lowerthan average, more difficult when SD is higher than average. Results show how tunnels in Brazil tend tobe unrealistically more difficult to excavate when compared to similar excavations in similar geologies elsewhere in the world. It is thoroughly discussed the reason for such anomaly (up to +90% SD compared to industrial average). One reason could be the lack of options amongst explosive products on the brazilian market. Only ANFO and explosive emulsions are available in Brazil. Lacking high VOD(Velocity of Detonation) products might result in reducing the maximum allowable burden amongstproduction holes, therefore increasing SD. Another reason could be found in the tunnel designers’tendency of choosing D&B as excavation method for weak rock masses that would benefit from mechanical excavation. The reason to this tendency can be partly found in the lack of availability of mechanical excavation machines in the brazilian market. Blasting in weak rock masses requires more careful smooth blasting, hence a closer spacing amongst contour holes to avoid costly overbreak: this increases SD. A third reason could be found in the lack of skill amongst the local workforce. When dealing with unskilled workers the blast designers naturally tend to avoid highly optimized blasts thatrequire very skilled workforce to be realized on field. The designer in this case tends to leave the blastdesign simpler but more robust, at the cost of higher specific drilling and specific charge. The conclusions suggest that this unrealistic difficulty when compared to world average could be a simptom of the so-called “Brazilian cost” within the tunnelling industry."

Jan 1, 2017

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 A T. Spathis

Corrections are given for “A three parameter rock fragmentation distribution” by A.T. Spathis (Measurement and Analysis of Blast Fragmentation, Workshop hosted by 10th International Symposium on Rock Fragmentation by Blasting, New Delhi, India, November 25-29, 2012 pp. 73-86). Typographical errors in two equations for the uniformity index in the two versions of the original and modified Kuz-Ram model are corrected. It is noted that the modified equation in the original published paper of Cunningham also had the same typographical error. A corrected plot of the dependence of the uniformity index versus the burden to diameter ratio is given. These corrections do not affect the rest of the original published paper.

Jan 1, 2013

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 Jeff Dean

As the Society celebrates its 35th year as an explosives industry association, it is clear that we are part of an industry that covers many sectors of economic activity. We are the voice of those who use, transport, store, manufacture, and dispose of commercial explosives products and others that serve the end user of explosives products. Along with other associations in this industry, we have a combined membership of hundreds of companies and tens of thousands of individuals in the U.S. and around the globe.

Jan 1, 2010

By John A. Davis, David W. Brunton

(Excerpts, pp 157-160) The usual means of firing blasting charges, especially in tunnels and adits in the Western States, is by the use of a safety fuse. The term safety fuse originated from the fact that when properly used under working conditions this fuse burns at a uniform rate and does not flash or explode, as was often the case with the means employed for igniting blasting charges previous to its invention; but the term is somewhat misleading, because the fuse is not, nor has it ever seriously been claimed to be, safe for use in gaseous coal mines. The fuse used for tunnel work is composed of a core of gunpowder surrounded by various layers of waterproofing material.

Jan 1, 2015

By Ali Kahriman, Abdulkadir Karadogan, Alper Celtikci, Ahmet Varol, Ertugrul Kaya, Turgay Ozat

This paper presents analysis of environmental effects induced by cautious blasting during the construction of the Istanbul Subway 4 Levent - Ayazaga Darulsafaka Metro Tunnel Project carried out by the contractor, located at Northern Istanbul in Turkey. Within the scope of the study, for the prediction of the peak particle velocity and to determine the slope of the attenuation curves together with the maximum charge per delay for the S6-7-8 shafts of this tunnel route, ground vibration components were measured carefully by using five vibration monitors during the construction of the tunnels which required blasting. The particle velocities and frequency values of all blast events are evaluated according to the United States Bureau of Mines (USBM) and German DIN 4150 Norms in order to predict, and compare the influence grades to the neighboring buildings, and structures. Also, data pairs of scaled distance and peak particle velocity obtained from 107 records belong to 51 shots were analyzed statistically. Empirical relationships with correlation at the 95 % confidence interval were established for these tunnel excavations and suggested for the test sites in order to estimate particle velocity of the ground vibrations. As a result of the studies, some practical charts are created in order to minimize the psychological effects of the shots, and simplify the authorities of shots’ job. And last but not least, make sure that the shots will be done in a controlled way.

Jan 1, 2011

By Lifent Li, Jhon Silva-Castro

Since millisecond-delay detonators were first introduced, at least two variables, among others, have been more closely considered when timing a mining blast: the accuracy and the precision of the initiation system. Currently, most mine blast design software has the capability to use the precision/accuracy of the firing system and display the overlap timing window between charges in any given time interval (8 ms, 3 ms, etc.). Despite these technological advances, there are still situations which result in the overlapping of charge timings. The consequences of overlapping charges involve flyrock events, fragmentation and diggability problems, and other inconvenient situations affecting the operation of the mine.

Jan 1, 2015

By Kain Petterson, P D. Katsabanis

Blast fragmentation, determined using image analysis was correlated to drill monitoring parameters in an open pit operation. Average fragment size and 80% passing size showed strong correlation with specific energy of drilling as well as with torque, while the same passing sizes did not correlate well with the rate of penetration. It was also determined that the uniformity of fragmentation decreases with the specific energy of drilling. Thus drilling monitoring parameters appear to be valuable in determining the blastability of the rock mass, enabling adjustment of blast loading to respond to changing conditions in the rock mass.

Jan 1, 2013

By T. G. Sitharam, P. B. Choudhury

Prediction of ground vibration (peak particle velocity, PPV) and frequency is an important task in geoscience. Till date, many empirical equations are derived from conducting trial blasts in the mines, to arrive at attenuation predictors. These predictors are usually site dependant and hold good for one particular type of rock/strata. These predictors cannot be used for geologically different rocks/strata. This paper presents the application of support vector machine (SVM) model, for predicting blast induced ground vibration and frequency, using a one comprehensive model for three different types of rock. Inputs to the SVM model formulation involve twenty one parameters consisting of geotechnical properties of the rock mass, blast design geometry and explosive properties, and the output of the formulated model is peak particle velocity and its associated frequency. The data has been acquired from eight limestone mine, five coal mine and two manganese mines. The comprehensive SVM model is formulated using 400 datasets and tested with 143 datasets. The performance indicators to the model not only justify its formulation but also the advantages it has over site specific predictor models. The SVM model not only predicts PPV, with higher correlation coefficients as compared to predictor equations, but also the associated frequency.

Jan 1, 2010

By William Nicoll

Those who use electric detonators in firing blasts will be interested in a new electrical testing instrument known as the ‘Blasters’ Friend’, recently devised by the New York Blasting Supply Co. of New York. Owing to the necessarily delicate construction of the platinum wire bridge in the shell of a detonator, it frequently happens that it becomes broken or disconnected; thus destroying the circuit and rendering the detonator worthless. In many cases, misfires and premature explosions are caused by defective detonators. Heretofore, to detect the deficiencies of a detonator before using has been an impossibility, owing to the absence of a testing instrument adapted to the purpose.

Jan 1, 2010

By C. Adcock, R. Farnfield, G. Adderley

The use of explosives to create special effects in the film industry is a well-known past time. A recent production required simulation of a large scale water splash from the effect of a statue falling from a cliff edge and impacting on an open body of water. This was to be achieved through the use of precisely delayed explosions detonated near the surface of the water. A survey of the area revealed a breeding farm for sea bass approximately 250 metres (273 yards) from the intended blast area. It was initially thought that the water pressures produced for the detonation of the explosives may cause harm to the fish. Much work has been carried out over the past few decades on the effect of open water blasting and its effects on aquatic wildlife; this includes water pressure modelling techniques which can be used as predictive tools.

Jan 1, 2010

By N Gkikizas-Lampropoulis

Selection of delay times to optimize fragmentation has been a controversial topic among researchers and blasting practitioners. This paper interprets previous experimental information on the effect of delay on fragmentation with the aid of some new experimental observations of the time of detachment of the free face of the blast as well as results of numerical modelling. It was shown that detachment of the burden occurs at delays shorter than the one which produced optimum fragmentation in the experiments, suggesting some fragmentation improvement due to gas action. In addition, at the spacing to burden ratio of the experiments, the damage zone from an earlier detonating charge extends the distance to the neighboring charge, essentially affecting the burden of some of the holes of the blast, at detonation time. Computer modelling demonstrated that increased spacing results is less overlap of stress induced damage zones meaning that there is less influence of delay on stress wave induced fragmentation. It was also shown that simultaneous initiation results in less back break, while increased back break may result even with short delay times.

Jan 1, 2016

By Frank Sames, Brad Terhune

In many construction projects and in most quarrying operations drilling and blasting remains the only feasible method of loosening rock in the removal of rock or overburden, the development of the quarry and in the production process of crushed stone. Often, a blasting plan is required for the project or the quarry’s permit with primary concerns over safety and site security, and compliance with environmental regulations or standards. From this plan, a blasting program has to be developed considering the varying requirements of production, the advance of the mineral extraction and the environmental impact. The actual blast design requires a planning and optimization process. This optimization process is driven by the blasting technicians/engineers, project or mine management and often by community concerns. The blast design process comprises the selection of blast parameters, including the explosives, and the actual layout of the blast. Design tools and controls range from conventional methods based on established blasting practices to advanced design tools or computer models. Blast monitoring and evaluation can also range from empirical to advanced blast assessment. The data and information from each blast or a series of blasts can further be used in the optimization process. Its success depends upon recording the data, the timely transformation of the data to relevant information, and the development of process oriented knowledge. The elements of the blast design process are summarized and described with examples of state-of-the art engineering controls. The reporting and monitoring of individual blasts is discussed with respect to data management and information systems. A conceptual overview of the components and interfaces of a blasting program is given and discussed on the background of technical, management and community concerns.

Jan 1, 2004

By Anderson Meireles, Vladimir Carrasco, Carlos Feliciano

Adopting new technology in drill and blast requires a structured implementation process, as it represents a significant change in a traditionally conservative industry. It involves addressing initially unknown implications. As the problem is not yet acutely felt, developing a market strategy must be approached from the customer’s perspective, considering how the product can optimize their activities or enhance flexibility. To achieve this, it is essential to have a comprehensive understanding of the context of the customers identified in the deployment process pipeline. This paper discusses aspects of introducing wireless initiation technology - the initiation of primers through a magnetic field without physical connections - in Brazil. Additionally, it presents a case study of the application of a structured process of sales with purpose in an underground mine. By identifying key opportunities that were highly profitable for the client, the necessary awareness was created, leading them to recognize the technology as an enabler for exploring their mineral deposits in a new way which allowed a successful change management process. Based on the applicable technique, a preloading project was developed to maintain inaccessible areas with high-grade precharged with the area loaded with wireless primers acting as a temporary pillar and controlling dilution throughout the orebody. Once the excavation of the stope was completed, the pillar was successfully blasted and the material - once considered lost in the original plan as a rib pillar - was recovered after serving its structural function. Through this method, the metallic recovery of the stope increased without dilution losses. Demonstrating economic viability and stablishing the previously unknown technology as a strategic tool for optimizing stope recovery.

Jan 21, 2025

By Joshua Hoffman, Braden Lusk, David McLane, John Rathbun

The dynamics of explosive detonations are understood; however recreating a real-world, to-scale scenario is costly. The use of a shock-tunnel allows testing to be done on a smaller scale, with the simulated effect of a large explosion. Analyzing explosive waveforms using this method can greatly reduce cost in testing blast-resistant products, such as anti-terrorism devices, mine safety products, and military equipment. The purpose of this project is to better the understanding of how the waveform dynamics of an explosive detonated within a shock-tunnel differ from those in an open-air arena test.

Jan 1, 2011

By Robert Hopler

After the disbanding of the Gunpowder Trust Association in 1904, the Association of Independent Powder and Dynamite Manufacturers was formed, followed in May of 1906 by the formation of the Association of Manufacturers of Powder and High Explosives. Due to a lack of success in attracting all manufacturers to membership, these organizations did not survive.

Jan 1, 2014

By Clarence Hall, Charles E. Monroe

Squibs, Fuse, and Detonators It has been made clear in the discussion of combustion and explosion and the description of various explosives that they can be caused to explode by various means. All of them can, under some circumstances, be made to explode by fire. Some of them can be caused to undergo a detonating explosion by setting off a detonator in contact with them. In blasting use is made of both these means for setting off explosives, the means used being determined by circumstances.

Jan 1, 2010

By Tristan Worsey

This work was performed during the summer of 2008 during the junior year of a BS in Mining Engineering. It was observed that the mine was having a problem with back break during the blasting of development drifts. The unwanted back break was causing the mine extra costs in ventilation, ore dilution, ground support, back fill, explosives and man-hours. The blasting practices were observed for four weeks and the problems and their solutions were defined. In this paper the reasons and causes of the problem are explained with the proposed solutions to eliminate back break.

Jan 1, 2010