Item: Determining the equivalent explosive effect for different explosives
Title: Determining the equivalent explosive effect for different explosives
Proceedings: Proceedings of the 1994 International Snow Science Workshop, Snowbird, Utah, USA
Authors: Jerome B. Johnson, U. S. Army Cold Regions Research and Engineering Laboratory, P. O. Box 35170, Ft. Wainwright, AK 99703-0170
Abstract: Explosives with different amounts of available chemical energy per unit mass (specific energy) have the same explosive effect when the total available chemical energy (detonation energy) for the explosives are equivalent eml ml = em2 m2 = Et where em}, em2 are the specific energies and ml and m2 are the masses for two different explosives and Et is the total detonation energy. The mass of explosive 2 needed to produce the same explosive effect as explosive 1. The specific energy can be estimated from em = ey/ PO where ey =-4.7613 +1.6923 D is the amount of available chemical energy per unit volume, D is the unconfined detonation speed (km/s), and Po is the explosive initial density (Mg/m3). The effectiveness of a low detonation speed explosive will be similar to that of a high detonation speed explosive when their total detonation energies are the same. The perception that high detonation speed explosives are more effective than low detonation speed explosives at causing snow avalanche failure is a result of comparing explosives with equivalent mass rather that equivalent total energy and the fact that the Chapman-Jouguet pressure of an explosive is strongly dependent on detonation speed.
Keywords: chemical energy, explosive, detonation
Digital Abstract Not Available