The MSK-78 intensity scale and seismic risk

An attempt has been made to incorporate macroseismic intensity into the evaluation of seismic risk. On the basis of the descriptions given by the MSK-78 scale some basic curves were constructed which show the percentage of damaged structures as a function of the macroseismic intensity grade for three different types of structures and five different categories of damage. The vulnerability functions of the populations of structures of type A, B, and C were calculated from these curves, assuming a certain relationship between the degree of loss and the category of damage. The corresponding seismic risk is then defined by a convolution of the vulnerability of the population of structures concerned and the seismic hazard of the area. In a similar way, seismic risk could be evaluated for other elements at risk, too. Seismic risk functions for the populations of structures of type A, B, and C and for inhabitants of these buildings are presented as an example for a given distribution of seismic hazard.