ABSTRACT
Engineering considerat ions of ea r thquakes are the ea r thquake load and the safety of engineering works against it. Before the occurrence of an ear th quake , engineers need to know the possibility of a certain strength and repeti t ion ra te of g round mot ion occurr ing at a site and the dynamic proper t ies and strength of the engineering works in order to design future works safely and economically and to know the possible behavior of existing works if such an ea r thquake occurs and the necessary measures tha t should be taken. The social considerat ions of ea r thquakes are similar bu t more on the side of safety, economic risk and political or public measures of disaster reduct ion .
