A History of Research and a Review of Recent Developments

The analysis of detonation and shock in free air 15
plinths at certain RAF stations, but it is best not to stop! According to records,
68000 high capacity versions of this bomb were released over enemy territory
between 1941 and 1945. Barnes Wallis has a further famous place in military
history in connection with the design of bombs to destroy the main structure
of dams, and with the development of the Tallboy and Grand Slam bombs
(see section 7.3).
The characteristics of explosives are nowadays often presented dimensionally
on a log log scale as a relationship between the peak instantaneous overpressure
in bars and the distance in metres in any direction from the centre of the
explosion of a spherical charge. Figure 1.5, due to Lavoie [1.16], gives a
comparison for 1000 tons of TNT, FAE and a nuclear explosion. The peak
overpressures close to the explosion vary considerably, as might be expected,
but in all cases have diminished to 0.1 bar at a radius of 100 or 200 metres.
Figure 1.6 from the same source compares impulses for similar explosions,
and shows that, because of the duration of the positive phase, much more
impulse is available from nuclear and FAE explosions than from TNT.
Some time after the end of the Second World War photographs of the first
atomic explosion in New Mexico were released, and a year or two later, in
1949, a paper on the formation of a blast wave from a very intense explosion,
written by G.I.Taylor [1.17] in 1941 for the Civil Defence Research Committee
Figure 1.5 Overpressures for 1 KT explosions (from Lavoie, ref. 1.16).