Issues in Urban Earthquake Risk

Urban seismic risk is growing worldwide and is, increasingly, a problem of developing countries. In 1950, one in four of the people living in the world's fifty largest cities was earthquake-threatened, while in the year 2000, about one in two will be. Further, ofthose people living in earthquake-threatened cities in 1950, about two in three were located in developing countries, while in the year 2000, about nine in ten will be. Unless urban seismic safety is improved, particularly in developing countries, future earthquakes will have ever more disastrous social and economic consequences. In July 1992, an international meeting was organized with the purpose of examining one means ofimproving worldwide urban safety. Entitled "e;Uses ofEarthquake Damage Scenarios for Cities of the 21st Century,"e; this meeting was held in conjunction with the Tenth World Conference ofEarthquake Engineering, in Madrid, Spain. An earthquake damage scenario (EDS) is adescription of the consequences to an urban area of a large, but expectable earthquake on the critical facilities of that area. In Californian and Japanese cities, EDSes have been used for several decades, mainly for the needs of emergency response officials. The Madrid meeting examined uses of this technique for other purposes and in other, less developed countries. As a result of this meeting, it appeared that EDSes bad significant potential to improve urban seismic safety worldwide.