Fundamentals of Earthquake Engineering

Libro: Fundamentals of Earthquake Engineering
Autor: Newmark-Rosenblueth
Editorial: Prentice hall

In this text on earthquake engineering we take for granted that the purpose of design in engineering is optimization, and that we deal with random variables. In the past the orthodox viewpoint maintained that the objective of design was to prevent failure; it idealized variables as deterministic. This simple approach is still fruitful when applied to design under only mild uncertainty, and in situations in which the possibility of failure may be contemplated at such a distant future as to be almost irrelevant; but when confronted with the effects of earthquakes, this orthodox viewpoint seems so na’ive as to be sterile. In dealing with earthquakes, we must contend with appreciable probabilities that failure will occur in the near .future. Otherwise, all the wealth of this world would prove insufficient to :fill our needs: the most modest structures would be fortresses. W e must also face uncertainty on a large scale, for it is our task to design engineering systems-about whose pertinent properties we know little-to resist future earthquakes and tidal waves-about whose
characteristic we know even less