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By Y. Hirosaki, H. Hamashima, Y. Itoh Kato, S. Tanaka

The emulsion explosives show non- ideal detonation behavior, and its detonation velocity can be controled by selecting the size and adjusting the quantity of voids involved. To establish the technology to control the detonation characteristics of the emulsion explosives, some experiments have been carried out using resin balloons of five different sizes ranged from O.OSmm to 2.42mm in the average diameter. Detonation velocities of the emulsion explosives containing resin balloons of different size and quantity were determined for the charge diameter of 20-50mm. The detonation velocity at infinite charge diameter was compared with calculated ideal detonation velocity. The emulsion explosives containing large (0.5mm or larger) balloons showed big discrepancy between the measured and calculated detonation velocities, and the fraction of ammonium nitrate reacted in the reaction zone was estimated to be significantly low. It was shown that the reaction zone length was proportional to the size of voids involved. The critical charge diameter was determined for the emulsion explosives containing different resin balloons at the various explosive densities. It is large for the emulsion explosives containing large voids, and it was shown that the critical diameter is proportional to the distance between the void surfaces, not to the void spacing, the distance between the centers of the voids. The reaction rate of the bulk emulsion matrix seems to be the major factor that affects the critical diameter than the specific surface of voids. Good relationship between the critical diameter and the reaction zone length was observed.

Jan 1, 2000

The underwater explosions have been used for several decades for the determination of energy content of explosives. This test method is the only one by which shock, fly rock and total energy can be measured separately. It enables to develop the energy content of explosives for different purposes; the military high explosives should contain more shock energy whereas the fly rock energy is very important feature for the blasting explosives. The purpose of this study was to establish a test place for the underwater experiments in an old water filled open pit, to estimate the repeatability of the energy measurements, to calculate the standard deviations and to compare the total energy content of commercial explosives to the theoretical values calculated by the thermo dynamical program. The test method seems to work quite well especially for the homogeneous explosives. The difference between the energy content of theoretically calculated and measured values for the homogeneous emulsion explosives was about -3% and for the dynamite about -5%. The energy difference for the unhomogeneous ANFO was detected to be -19%. The diameter of the charge was 15 cm and it was obviously too small for ANFO to detonate ideally. On the basis of the test results this test method seems to fit best for the cap sensitive, completely homogeneous, spherical charges whose masses are big enough and which are initiated from the centre of the charge. The underwater explosions as a test method is the only one which can separate shock, bubble and total energies from each other and therefore makes it possible to develop the properties of explosives for different purposes which is very important feature of this method.

Jan 1, 2005

By Catherine T. Aimone-Martin, Susan G. Beattie

A series of small scale explosive tests were performed at a perlite mine near Socorro, New Mexico. The tests were designed to investigate the azimuthal or directional relationship between small scale geologic structures such as joints and the propagation of explosively-induced ground motions. Three shots were initiated within a single borehole located at ground zero at depths varying from 83 m (272 ft) to 10 m (32 ft). An array of three component velocity and acceleration transducers were placed in two concentric rings at distances of 20 m (66 ft) and 40 m (131 ft) surrounding the single hole at 7.5° , 15° , and 30° azimuths as measured from ground zero. Data from the transducers were then used to determine the average propagation velocity and waveform characteristics of the blast vibration through the rock mass at the various azimuths. The rock mass was mapped to determine the predominate joint orientations (strike and dip) and the average propagation velocities were correlated with this geologic information. The results showed that there is a correlation between the predominate joint orientation and ground motion amplitudes and velocity. The more predominate geologic structures allow the wave to follow along their strike thereby forming a planar path of least resistance and in turn, allowing higher velocities and amplitudes. Secondary joints or structures may act in concert with more prominent features to form a network of channels or paths along which the wave moves more freely than it may when traveling against the structures. The greatest azimuthal variations in velocity and amplitude was observed for the shallow shot at 10 m (32 ft) depth.

Jan 1, 1996

By Marcia Harris, Richard Mainiero

The New York State Department of Transportation recently commenced highway widening and drainage improvement projects in Clarence and Amherst, NY. Drainage improvements including the installation of storm sewer lines required excavation to a depth of 2.5 m (8.2 ft). In September 2002, NYSDOT stopped further blasting when 800 ppm CO was detected in the basement of a house near the blasting site. At the insistence of NYSDOT, the general contractor developed a new blast plan with the assistance of an environmental consultant. The plan provided for the installation of multi-gas monitors in buildings of special concern and/or with basements and residential type CO monitors in all other buildings within 100m (330 ft) of the blast. The multi-gas monitors would be remotely monitored. The plan provided action levels which would ensure public safety. The blast design was also modified to allow for better venting of CO. Blasts were limited to 20 ft lengths. The overburden was to be removed from the rock and blasting mats put in place to prevent flyrock. Approximately twenty feet of trench adjacent to the blast was left open to allow ground movement and gas release. The use of CO monitors was effective to alert occupants of a building to the presence of CO. The most effective appeared to be the residential type CO alarms with digital readouts. They were simple and easy to use and allowed the public to participate in the process. False alarms were repeatedly received with the more sophisticated instrumentation. Residential type CO monitors are preferable to warn people near blast sites. More sophisticated instrumentation should be avoided unless personnel are experienced in its use. A general overview of the blasting and monitoring is presented and discussed. The use and effectiveness of residential type CO monitors and multi-gas monitors are discussed.

Jan 1, 2004

By Lawrence Mirabelli, Wayne Lidkea, Mario Paventi

On Januarv 1, 1996, INCO Limited, Tamrock OY, Dyno Nobel and CANMET formed a consortium for the development of robotic mining equipment called the Mining Automation Program (MAP). This project was a tive- [5] year research and development program that combined the talents of the above organizations to facilitate the development of mining equipment and systems for tele-remote mining. The year 2000 brings MAP to conclusion with actual production process trial testing of the developed prototype equipment and systems during the period between May and October. MAP consisted of multiple projects all of which are based on the communication system developed by INCO Mines Research and currently sold and marketed by Automated Mining Systems Limited. The main projects include the development of a positioning and navigation module (including a software mapping system that will be inherent to each piece of equipment), robotic systems for underground development and stoping operations, as well as software systems to support the use of this equipment. Included in the program was the establishment of a Research Mine, at INCO’s 175 orebody, Copper Cliff, Ontario, Canada. This facility allowed for the on-site collaboration between the companies and research organization in the design and testing of techniques and equipment to mine with TeleminingTM. Some of the prototype equipment developed through the program are: a tele-operated drilling jumbo, a tele-operated load-haul-and-dump [LHD] tram, a tele-operated production drill, a remote initiation system for programming and detonation of electronic detonators, and the development of a vatiable energy bulk emulsion explosive system, including loading equipment, to deliver the explosives to boreholes. Use of tele-operated and automated equipment for mining mandates a dramatic change in the traditional drill/blast/muck/support cycles in the underground mining process.

Jan 1, 2001

By Dae-Woo Kang, Sang-Wook Kim, Shin Lee

The Air-tubes blasting method is provided in which a series of aligned boreholes are charged with explosive s and air tubes in a predetermined blasting pattern. The air tube is composed of cylindrical flexible tubes which have a predetermined width and length to be fit with the site boreholes. Within a preferred formation, each borehole is charged with the explo sives and detonators with an air tube installed just above the explosives. Stemming materials are filled above the air tubes. At the limestone mine of Sung-Shin Cement Co., in South Korea, these blasting tests were performed by a diameter 102 millimeter and 15 m long boreholes with the charging length of explosives was 8m to 10 m by the total weight of explosive 40 to 50 kg with 3m to 6m air tube which has a 76 mm diameter, and 1m to 3m stemming cover. Blasting results showed the about 10% to 30% explosives savings available and especially, the about 20% to 50% reduction of ground vibration with the low noise measures around 2dB to 5dB by this new blasting method which was compared with the conventional blasting methods. The explosives and air tubes may be alternately charged along the boreholes. The use of air tubes which were charged above an explosive layer allow to form the quantitative air decking in every blast hole. Therefore, the Air-deck effect can be easily obtained through this blasting method, and also easy to increase the fragmentation rate resulting in the more suitable mucking procedures at the working site with the minimum usages of explosives for the better economic operations in mine quarries.

Jan 1, 2005

By Thomas E. Lobb, Harry C. Verakis

Blasting is a primary means of extracting minerals and ores at surface mining operations. The domestic consumption of explosives and blasting agents during the year 2001 was about 5.25 billion pounds. Flyrock is always a major concern for the blaster. Flyrock from surface blasting operations has caused serious injury and death to employees and other persons. Injuries due to flyrock and the lack of blast area security accounted for over two-thirds of all blasting-related injuries in surface coal, metal, and nonmetal mines during the period 1978-2002. Selected accidents due to flyrock and lack of blast area security in surface mining are presented in this paper. Incidents related to construction blasting are also described. Techniques to mitigate blasting accidents are discussed. These include proper blast design, driller-blaster communication, inspection prior to loading and firing the blast, removing employees from the blast area, controlling access to the blast area, and using a blasting shelter. An experienced driller could detect potential problem areas such as voids, mud seams, incompetent rocks, and other irregularities by observing the progress of drilling. The drill log should include the details of any unusual or exceptional circumstances noticed during drilling. A blaster may need to alter the loading configuration to alleviate potential problems. Basic blast design is sometimes taken for granted and assumed to be proper for the conditions encountered, but one size does not fit all. It is known from the physics of blasting that the explosive energy takes the path of least resistance. The path of least resistance could generate flyrock, depending on the blast site conditions. A combination of ‘borehole tracking’ and ‘laser profiling’ can assist in improving the design of a blast. The blaster can use these tools to adjust borehole loading to match site conditions.

Jan 1, 2004

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 Paul Worsey, Attila Szucs, Mark F. C. Schmidt

The use of water stemming with small explosive charges has been successfully developed at the University of Missouri-Rolla. Further study has been started to explore additional applications and uses for water stemming. Work has been focused in the areas of rock excavation and perimeter blasting techniques. This ongoing work is being conducted internally as graduate and undergraduate level research. A paper describing the general technique for use with boulder fragmentation was published in last year’s proceedings. The excavation work took place in the form of both small bench and trench shots while pre-split and trim shots comprised the perimeter-blasting portion. The excavation work was located in both the Roubidoux sandstone formation and the Jefferson City dolomite formation. Hole diameters ranged in size from 1.5” to 3” diameter and powder factors ranged from l/l 0 to l/3 of the conventional charge weight. The water was used to both couple the explosive charge with the surrounding borehole, as well as stemming. No other stemming material or products were used. The method of using water stemming in perimeter blasting was found to work well. However, when used for excavation purposes, adequate rock movement was not obtained. The rock was often split, but not fragmented. The airblast was surprisingly low, but the ground vibrations were excessive. This is not the case with trim shots, and therefore this method appears ideal for splitting purposes, especially in areas where people do not like to stem the tops of the holes, and where airblast and vibrations are of concern. Water coupling dramatically increases splitting and fracturing. However, fragmentation is not only fracturing but also the movement and swelling of the material. As the charge weights are reduced with this method, sufficient gas volume is not created to cause this necessary movement and swell, which is critical in rock excavation. This explains why its successful application was limited to perimeter blasting applications.

Jan 1, 2000

By Peter Moser

The average annual consumption of raw minerals in Europe is 10 ton per person. About 50 % is produced by blasting. For a population of 450 million (including the population from the countries of the new member states) this makes 2.25 billion tons of blasted rock, 80 % being building industry aggregates and industrial minerals. In aggregate quarries 10-15 % of the rock blasted can’t be sold, as the material is too fine, i.e. smaller than 4 mm. This ‘fines problem’ is worse in the quarries of limestone and cement producers where up to 30 % of the material is useless. Thus about 450 million tons of useless rock fines are produced and put on waste dumps every year, i.e. 1 ton/person. This problem is addressed by the research project LESS FINES - “Less Fines production in aggregate and industrial minerals industry” which is funded by the European Union under the project contract G1RD-CT-2000-00438. The project consortium, formed of nine partners from 5 EU countries, works on the following two main research subjects: 1. The determination of the natural breakage behavior (NBC) of the rock mass, which is defined as the particle size distribution curve for a certain rock mass with the maximum uniformity and thus for a given maximum particle size that fragmentation curve which gives the minimum amount of unusable fine material. The comparison between the NBC and an actual blast fragmentation curve allows to quantify the fines reduction potential. 2. The adaptation of explosives properties, charging techniques and timing in order to produce only the minimum, inherently unavoidable percentage of fines. With about 15 full time working persons the project is estimated to be one of the largest blast related research activities in Europe at the time of the project period. The project is coordinated by the Department of Mining Engineering& Mineral Economics of the University of Leoben.

Jan 1, 2004

By Kirlk Yeager

"Ammonium nitrate (AN) is commonly mixed with a wide variety of additives to produce specialty formulations. Two additives commonly utilized are sodium nitrate (SN) and sodium nitrite (SNi). Application of the nitrite is primarily limited to gassing of emulsions. The nitrate, however, is incorporated in a wide variety of formulations. The effect of both these materials on the thermal stability of AN was examined. Experiments initially utilized lab-scale testing methods (sub-milligram sample size), such as differential scanning calorimetry (DSC), with scale-up to cook-off analyses (16 g) eventually applied. Labscale testing indicated that the presence of SN and SNi (both at 5 wt%) produced no harmful effects on the thermal stability of AN. The cook-off results did not agree with those from the lab-scale analyses, with both SN and SNi creating tremendous thermal destabilization of AN. These effects were seen at additive levels as low as 0.1 wt%. When SNi was employed as the additive, cook-offs became violent enough to create explosions in the testing apparatus. Although SN did not create as spectacular a destabilization, it did lower cook-off temperatures to approximately the same level as SNi. The dangerous situation created by SN andSNi seemed to be limited to cook-offs conducted in sealed vessels. If the SN/AN or SNi/AN formulations were allowed to cook-off in vented vessels, the thermal destabilization of AN did not occur. These results seemed to indicate that even “trace” amounts of what might ordinarily be viewed as benign additives could create significant destabilization of AN-based explosives under proper circumstances. Conditions created by blocked pumps, or deep boreholes could well overlap those produced in sealed cook-off vessels. In addition to showing the hazards potentially created by “benign” additives, the study also stressed that experiments designed to evaluate thermal hazards must include duplication of field variables to the fullest extent possible. "

Jan 1, 1999

By B. Corrêa, M. Cavalcante

A large open pit iron ore mine in Brazil, which has a heterogeneous lithology, faces a challenge in defining drill and blast patterns to achieve the expected results. The mine needed to obtain an automated representation of the fragmentation curves and correlate them to the respective blasts, lithologies and quality parameters, seeking the continuous optimization of the fragmentation process and its benefits to the subsequent comminution processes. Trials were carried out for 5 months to demonstrate the functionality of an autonomous fragmentation monitoring system that analyzes the granulometric curve of the material throughout the muckpile and makes the results available online and in real time. The system, which contains a binocular camera, a processing unit and an antenna, was installed in a shovel, to evaluate the following KPI's: monitoring failures, monitoring capacity, physical availability and reportability of oversized boulders. The system analyzed 33,060 samples, with an average capacity of 285 photos every 24 hours, 127 during the day and 158 at night, all measured, analyzed, stored, and made available on its online platform, reporting 223 alerts of P80 above 400mm (15.7 in) and 38 particle sizes above 900mm (35.4 in). The inactive and operational hours of the monitoring system corresponded, respectively, to the idle and worked hours of the shovel, according to dispatch data. There were no camera or processor failures, and rain, dust or poor internet conditions did not impact sampling and fragmentation analysis, indicating 100% physical availability of the system. The autonomous monitoring analyzed 139 times more samples compared to the currently used manual method. In addition to increasing sampling representativeness and automating the process, it increases the safety, quality, and productivity of granulometric analysis, eliminating the exposure of people in the mine and human bias in the analyses. Additional analyses were performed by correlating digitally centralized drill and blast data, data from autonomous drills and fragmentation results. Automated obtention of granulometric curves favors quick decision-making and optimization of blasts to achieve better results in productivity and cost reduction in the plant and mine operation. The autonomous fragmentation monitoring system met the need presented by the mine, proving to be a key tool in continuous improvement projects, including Mine to Plant.

Jan 1, 2024

By Richard Mainiero, James H. Rowland III

For many years there have been small scale tests available for evaluating the toxic fumes production by capsensitive explosives (DOT Class 1. l), but these could not be used with blasting agents due to the large charge sizes and heavy confinement required for proper detonation. Considering the extensive use of blasting agents in construction and mining, there is a need to determine the quantities of toxic ti,tmes generated by blasting agents. At the International Society of Explosive Engineers Twenty Third Annual Conference on Explosives and Blasting Technique in 1997, the authors reported on a facility for detonating large (4.54 kg), confined blasting agent charges in a controlled volume that had been constructed at the National Institute for Occupational Safety and Health’s Pittsburgh Research Lab’s Experimental Mine. Since 1997, this facility has been used to collect data on toxic fumes produced by the detonation of various ammonium nitrate/fuel oil (ANFO) mixtures and several cap-sensitive explosives. ANFO composition ranging from 1 to 10 percent (pet) tieI oil have been studied. As expected from previous studies, with an increase in fuel oil content the carbon monoxide production increases, while nitric oxide and nitrogen dioxide production decrease. The detonation velocity varies from 3,000 to 4,000 m/set for the 1 to 10 pet range of fuel oil content, suggesting that ANFO mixes with improper fuel oil content may appear to detonate properly, while their fume production differs significantly from optimum. The study also considers such factors as degree of confinement, water contamination, and aluminum content on blasting agent fume production. Results indicate that water contamination of the ANFO has little effect on carbon monoxide production, but causes significant increase in nitric oxide and nitrogen dioxide production. Decreasing confinement from Schedule 80 steel pipe to 0.4~mm thick sheet metal also has little effect on carbon monoxide production, but significantly increases nitric oxide and nitrogen dioxide production. Adding 5 and 10 pet aluminum to the ANFO had no clear effect on carbon monoxide, nitric oxide, or nitrogen dioxide production.

Jan 1, 2000

By Per-Anders Persson

This chapter deals with the concepts of shock wave8 and detonation wavea together, because a detonation wave is really a shock wave, supported by the explosive reaction that the shock wave ignites and propagates as it travels through the explosive material. In the context of rock blasting, furthermore, there is justification for treating shock waves and detonation waves together, because the mechanical effect of the detonation in an explosive in a drillhole in rock is propagated and its effects are spread throughout the surrounding rock by means of a shock wave. The overall performance of an explosive in rock blasting or any other application is of course dependent on how much thermal energy is released in the chemical reaction that occurs when the material detonates, and on how much useful mechanical work the reaction products can do as they expand. A major portion of thii chapter deals with the prediction and measurement of explosive performance, a subject which is now still in a process of rapid development.

Jan 1, 1998

By Ed O'Connor, Per-Anders Persson, Manhong Zhou

This chapter deals with the concepts of shock waves and detonation waves together, because a detonation wave is really a shock wave, supported by the explosive reaction that the shock wave ignites and propagates as it travels through the explosive material. In the context of rock blasting, furthermore, there is justification for treating shock waves and detonation waves together, because the mechanical effect of the detonation in an explosive in a drillhole in rock is propagated and its effects are spread throughout the surrounding rock by means of a shock wave. The overall performance of an explosive in rock blasting or any other application is of course dependent on how much thermal energy is released in the chemical reaction that occurs when the material detonates, and on how much useful mechanical work the reaction products can do as they expand. A major portion of this chapter deals with the prediction and measurement of explosive performance, a subject which is now still in a process of rapid development.

Jan 1, 1997

By Jhon J. Silva Castro

Blast vibration records used in mining contain unwanted information in the form of noise due to long-period drifts, background noise, and noise due to the conversion of the analogue signal to a digital signal. When recorded signals from blasting are used to find other physical variables, such as going from particle velocity to acceleration or displacement, the additional information in the vibration signal can result in inaccuracies in the estimation of the peak values and more dramatically, the results in displacement or acceleration can be nonzero near the end of the record. There are different proposed methods to clean or filter the unwanted information from the signal. All of the methods are based on finding the best fit of the record average value (baseline) and then subtracting from the record under analysis to produce the desirable adjustment. Different criteria and functions are used to define the best fit. The function to use will depend on the shape of the record average values. The main characteristic of the baseline function is that it represents a low frequency wave. Such a low frequency wave can be a periodic function or a polynomial expression of nth order. According to the order of the polynomial expression, the baseline correction can be linear, parabolic or high order. In this document the detailed procedure and the results for the baseline correction of a blast vibration record using a periodic function and a polynomial expression of different order is presented. The results show that the drift problem when displacement is calculate using velocity records increases with the increase of the distance from the blast.

Jan 1, 2015

By Frank Huber, Ed Fulop, Neil Singh, Ron Elliott, Blair Gohl, Lewis Clarke

This paper covers the successful application of explosive compaction technology for the densification of the foundation soils for the seismic upgrade of the Seymour Falls Dam, Vancouver, BC. The original earthfill embankment constructed during 1958 to 1961 was upgraded in 2004 to 2007 to withstand the effects of a maximum credible earthquake. This paper provides general background information on the theory of the explosive compaction of soils, history of use, geology of the site, project constraints, explosives selection, blast designs, instrumentation used, problems encountered and solutions implemented, and the results achieved.

Jan 1, 2009

By Robert B. Hopler

The history of bulk loaded explosives begins with the loading of black powder and RRP (Railroad Powder) into vertical boreholes. The early air place, net of black powder and nitrostarch dynamites is covered, as are the brands and formulas of the nitroglycerinsensitized "Bagged" powders.

Jan 1, 1993

By L C. Taylor

Very small scale testing has been shown to be able to predict quite accurately, in many situations, the results of full scale testing. Small scale tests are more cost efficient, easily observed, and easily instrumented than full scale tests. Over the past 10 years small scale testing in the Dynamic Effects Laboratory at the University of Maryland has been used to successfully study the response of structures and soils to explosive detonation. Small scale testing has been successfully used to predict full scale results in underwater cratering and channeling, the loading (both pressures and impulse) on vehicles due to the detonation of buried charges, the positive effects of bottom shaping for military vehicles to reduce this loading, and the movement of obstacles underwater by explosive charges.

Jan 1, 2012

By Braden Lusk

This paper includes results from analysis of recorded Acoustic Responses of Structures to Blasting. The analysis was performed to determine specific characteristics of sounds experienced inside homes during blast events. Data was collected in a typical house within the Boone North No.2 Coal Surface Mine in Ashford, WV which was instrumented for several blast vibration and acoustic responses. The instrumentation consists of four acoustic microphones distributed throughout the internal areas of the house and three geophones buried near the house. Two additional channels collect the trigger signal and Air Blast information. For each blast event recorded by the system, the mine blast reports were used to obtain major blast characteristics such as distance from the blast to the instrumented house, weight of explosive used, number of boreholes, delays, and other important parameters. This information allowed study the relationship between the acoustic response and the blast design. From a database of 43 records, five records were chosen for complete analysis. These records were chosen based on distance from the blast to the house, and specific blast parameters. This paper presents the result of the relationship between the frequencies and amplitudes for the entire trace of acoustic records, the response due to ground vibration (GV), and the response due to air-blast (AB). Frequency content was obtained through Fast Fourier Transforms (FFT), using D-Plot software. The records have a typical shape that permits cutting and analyzing each part of the signal with respect to GV and AB separately. Some conclusions are reported concerning the relationship between blast parameters and acoustic response of structures.

Jan 1, 2009