A History of Research and a Review of Recent Developments

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Introduction
This breadth of experience led to the discovery of the explosive scaling law
which was mentioned earlier and which is still such a fundamental part of our
analysis of the effects of explosions on structures. It underlines the need for
cross linking in our training of engineers and scientists. The second reason is
to emphasize the quality of the British contribution to the science of explosions
in the early part of this century.
The fundamentals also owe much to three other outstanding British scientists.
The first of these was Horace Lamb, a mathematician born at Stockport in
1849 who was professor of mathematics in Manchester University from 1885
to 1920. He was the recognized authority on hydrodynamics and wave
propagation, among many accomplishments, and it was he who set down in
his famous book Hydrodynamics the physics of plane waves diffracted by
striking discs, cylinders or circular apertures in plane screens. He also focused
attention on the work of Riemman on the formation of shock waves, and to
the earlier work of Earnshaw on the mathematical theory of sound.
The second scientist was William John Macquorn Rankine, born in
Edinburgh in 1820, who was trained as an engineer. He became professor of
civil engineering at Glasgow University in 1855, and died at the relatively
early age of 52. He was the author of the first formal treatise on thermodynamics,
as well as a remarkable manual of civil engineering. He discovered the changes
in pressure, density and velocity of a gas passing through a shock wave, and
published this work in 1870. This analysis was of great significance in the
study of the behaviour of explosions, and was also discovered by Hugoniot in
Paris in 1889. Rankine, like Hopkinson, was outstanding in a number of
areas of physics and engineering at the same time.
The third scientist was Geoffrey Ingram Taylor whose work on the dynamics
of blast waves from explosive charges was of great value to the defence research
effort in Britain in the period between 1936 and 1950. His earlier papers dealt
with the propagation and decay of blast waves from conventional weapons,
but his later work was devoted to the behaviour of blast waves from the first
atomic explosion in New Mexico in 1945, and from underwater atomic
explosions. Readers are recommended to examine the collection of the scientific
papers of Sir Geoffrey Ingram Taylor, edited by G.K.Batchelor and published
by the Cambridge University Press in 1963. Volume 3 of this work deals with
the aerodynamics and mechanics of projectiles and explosions.
We are concerned in this book with the shock and dynamic loading acting
on structures from various types of explosion. The accuracy of the figures
depends on the quality of the instrumentation used to measure instantaneous
pressure, the variation of pressure with time, the duration of the pulse, and
the velocity of associated impulsive effects such as blast winds. In certain
instances the response of the structure influences the nature and level of the
applied dynamic loading.
Accurate measurement of pressure and duration first became historically
important during the rapid development of the science of military ordnance