Engineering Transactions, 62, 4, pp. 423–435, 2014

An Investigation of TNT Equivalence of Hemispherical PE4 Charges

Samuel E. RIGBY
University of Sheffield, Mappin Street, Sheffield, S1 3JD UK
United Kingdom

Poznan University of Technology, Institute of Structural Engineering, Piotrowo 5 St., 60-965 Poznan, Poland

The TNT equivalence of an explosive is given as the equivalent mass of TNT required to produce a blast wave of equal magnitude to that produced by a unit weight of the explosive in question. Currently, there is a lack of agreement in the literature on the TNT equivalence (TNTeq) of PE4. This paper presents a combined numerical and experimental investigation of TNTeq for hemispherical PE4 charges in far-field blast events. Experimental results are compared to a series of numerical analyses conducted with different masses of TNT explosive and conclusions are drawn in order to provide a more informed value of TNTeq. It is found that a TNTeq of 1.2 best describes the blast waves produced from PE4 detonations, and this factor is found to be invariant of the distance from the explosive when considering far-field events.
Keywords: blast loading; experiment; finite element analysis; TNT equivalence.
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Polish Academy of Sciences, Warsaw, Poland