Fragment impact

A great deal of experimental work has also been done to identify and quantify the ha2ards of explosive operations (30—40). The vulnerabiUty of stmctures and people to shock waves and fragment impact has been well estabUshed. This effort has also led to the design of protective stmctures superior to the conventional barricades which permit considerable reduction ia allowable safety distances. In addition, a variety of techniques have been developed to mitigate catastrophic detonations of explosives exposed to fire. 

Volume III. Warhead , AFATL TR-67-13-Vol-3 (1967) (Conf) E) L. Aemow J.J. Piechocki, Multiple Fragment Impact Damage Study , DA-18-017-AMC-3447 (A) (1967) (Conf) F) R.E. Vincent, Scaled Prototype Warhead Study for Dragon (Medium Anti-Tank/ Assault Weapon-Maw) , DRD-15 (1967) (Conf) G) W.H. Snyder C.R, Hoggatt, Performance... 

Figure B.6 Fragment impact phenomena for concrete structures.

Figure B.7 Fragment impact phenomena for steel plates.

Domino effect An incident which starts in one piece of equipment and affects other nearby items, such as vessels containing hazardous materials, by thermal blast or fragment impact. This can lead to escalation of consequences or frequency of occurrence. This is also known as a knock-on effect. 

It is important to note, that this approximation is only based on the pressure. The impulse of the shockwave and the fragment impact (e.g. from confined charges or fume-cupboard shields in lab) are not taken into consideration. 

R. M. Rindner and S. Wachtell - Establishment of Safety-Design Criteria for Use in Engineering of Explosive Facilities and Operations Report No. 3 Safe Distances and Shielding for Prevention of Propap ation of Detonation by Fragment Impact PA Tech Report DB-TR-6-60 Dec i960 AD 321962... 

The preceding equations and considerations form the basis for a Monte Carlo evaluation. For this purpose the solutions of Eqs. (10.184) and (10.185) as well as Eqs. (10.191)-(10.197) are evaluated N times. Each time we obtain values for x(t), y(t), x(t), and y(t), from which parameters of interest, e.g. the distance of fragment impact and the corresponding energy are easily derived. The procedure corresponds to that shown in Fig. 4.22. 

The initiation mechanism of an explosive when different mechanical stimuli such as impact, friction, firing pin impact or puncture, projectile or fragment impact, etc. are applied is similar and rather complex. The most acceptable theory that explains the initiation mechanism by mechanical stimuli is the so-called hot spots theory. 

Barker, M.A., Bass, J.F., Connor, J., and Hubbard, P.J. Response of Confined Explosive Charges to Fragment Impact, Proc. 8th Symposium (International) on Detonation, NSWC 86-194, Albuquerque, NM, 1985, pp. 262-273. 

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