The estimation of permanent damage caused to steel structures from such effects as bomb blast, earthquakes, or collisions from moving objects is a problem which has attracted the attention of engineers, especially over the past decade.
Analyses of the response of complete framed structures to dynamic loads have, to date, been very idealized, representing the structure as a simple mass-inelastic spring system. Some more precise analyses have, however, been made of the behaviour of specific types of beams under particular loading conditions, but the results have remained unco-ordinated. In the present paper an attempt is made to unify these by considering the mechanics of behaviour of a flexural element under general time-dependent loading conditions, the effects of high strain-rate sensitivity being ignored. The equations derived will then form a basis for analysis of framed structures, by satisfying joint equilibrium and compatibility requirements.
A number of examples are given, and the limitations of the method are discussed.
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