Abstract
The purpose of this paper is to analyze the mechanism of the scabbing phenomenon that occurs when an intense shock wave in a solid is reflected against a free surface. Only plane shock waves with normal incidence to the free surface are discussed. The shock wave is assumed to be initiated by the detonation of an explosive (especially TNT with a loading density of 1.5 g/cm3). The calculations are based upon values given by H. Jones and A. R. Miller (for the detonation pressure), D. J. McAdam (for the strength of the material at combined stresses), P. W. Bridgman (for the quantitative behavior of the material at very high pressures) and, finally, upon results from the author’s own experiments regarding the impulse and the pressure-time curve at detonation in contact with a metal surface. It is shown that fracture sometimes is likely to occur in several parallel layers of the material. Experiments have been performed which support the theoretical analysis. The research was carried out at the Royal Swedish Fortification and Works Administrative Service, Stockholm.
