TY - JOUR
T1 - Secondary shock features for large surface explosions
T2 - Results from the Sayarim Military Range, Israel and other experiments
AU - Gitterman, Y.
N1 - Funding Information:
The Sayarim experiments were supported by the US Army Space and Missile Defense Command (in 2009) and the Comprehensive Test Ban Treaty Organization, Vienna (in 2011). Thanks to collaborators from the WGC (J. Bonner), the UM (R. Waxler) and the UF (E. Marchetti) for supplementing data of close seismo-acoustic observations in 2011 experiment. The research group of the Protective Technologies R&D Center, Ben-Gurion University (G. Ben-Dor, O. Sadot and A. Britan) provided fruitful discussions of observed air blast wave effects and secondary shock features, and supplement of useful references. Thanks to C. Needham, J. Dewey, L. Sadwin and to anonymous reviewers for valuable comments to the research and the manuscript. I appreciate kind help of J. Bonner, R. Waxler and R. Hofstetter (GII) for essential improving the English and writing style of the manuscript. Research work of the author was supported by the Israel Ministry of Immigrant Absorption.
PY - 2014/1/1
Y1 - 2014/1/1
N2 - A series of surface explosions was designed and conducted by the Geophysical Institute of Israel at the Sayarim Military Range in the Negev desert, including two large-scale explosions: approx. 82 tons of high explosives in 2009, and approx. 100 tons of low-grade ANFO explosives in 2011. The main goal of the explosions was to provide large controlled sources for calibration of global infrasound stations designated for monitoring nuclear tests; however, the geophysical experiment also provided valuable observations for shock wave research. High-pressure gauges were deployed at distances between 100 and 600 m to record air blast properties and to provide reliable estimation of the true charge yield compared to the design value. Secondary shock phenomena were clearly observed at all near-source gauges as characteristic shock wave shapes. Secondary shocks were also observed at numerous seismic and acoustic sensors deployed in the range 0.3-20 km as acoustic phases. Empirical relationships for standard air blast parameters (peak pressure and impulse) and for a new parameter called secondary shock time delay, as a function of distance, were established and analyzed. The standard parameters, scaled by the cubic root of the estimated TNT yield, were found to be consistent for all analyzed explosions. However, the scaled secondary shock delays were clearly separated for the 2009 and 2011 explosions, thus demonstrating dependence on the explosive type. Additionally, air blast records from other experiments were used to extend the charge and distance ranges for the secondary shock observation, and showed consistency with the Sayarim data. Analysis and interpretation of observed features of the secondary shock phenomenon are proposed and a new empirical relationship of scaled secondary shock delay versus scaled distance is established. The results suggest that the secondary shock delay can be used as a new additional waveform feature for simple and cost-effective explosive yield estimation.
AB - A series of surface explosions was designed and conducted by the Geophysical Institute of Israel at the Sayarim Military Range in the Negev desert, including two large-scale explosions: approx. 82 tons of high explosives in 2009, and approx. 100 tons of low-grade ANFO explosives in 2011. The main goal of the explosions was to provide large controlled sources for calibration of global infrasound stations designated for monitoring nuclear tests; however, the geophysical experiment also provided valuable observations for shock wave research. High-pressure gauges were deployed at distances between 100 and 600 m to record air blast properties and to provide reliable estimation of the true charge yield compared to the design value. Secondary shock phenomena were clearly observed at all near-source gauges as characteristic shock wave shapes. Secondary shocks were also observed at numerous seismic and acoustic sensors deployed in the range 0.3-20 km as acoustic phases. Empirical relationships for standard air blast parameters (peak pressure and impulse) and for a new parameter called secondary shock time delay, as a function of distance, were established and analyzed. The standard parameters, scaled by the cubic root of the estimated TNT yield, were found to be consistent for all analyzed explosions. However, the scaled secondary shock delays were clearly separated for the 2009 and 2011 explosions, thus demonstrating dependence on the explosive type. Additionally, air blast records from other experiments were used to extend the charge and distance ranges for the secondary shock observation, and showed consistency with the Sayarim data. Analysis and interpretation of observed features of the secondary shock phenomenon are proposed and a new empirical relationship of scaled secondary shock delay versus scaled distance is established. The results suggest that the secondary shock delay can be used as a new additional waveform feature for simple and cost-effective explosive yield estimation.
KW - Air blast wave
KW - Delay as new yield estimator
KW - Delay dependence on explosives
KW - Secondary shock delay
KW - Surface explosion
KW - Yield estimation
UR - http://www.scopus.com/inward/record.url?scp=84898916107&partnerID=8YFLogxK
U2 - 10.1007/s00193-013-0487-y
DO - 10.1007/s00193-013-0487-y
M3 - Article
AN - SCOPUS:84898916107
SN - 0938-1287
VL - 24
SP - 267
EP - 282
JO - Shock Waves
JF - Shock Waves
IS - 3
ER -