INTERPRETING OF THE RECENT STRONG MOTIONRECORDS OBTAINED IN TURKEY (IZMIT-KOCAELIAND DüZCE-BOLU EARTHQUAKES)AND ROMANIA (VRANCEA EARTHQUAKES)

摘要

On scale recordings of strong ground shaking are important for understanding causes ofearthquake damage and for advancing design codes. In 1999 two major earthquakes thatoccurred in the North Anatolian fault system devastated Turkey. In the last 25 years threemajor Vrancea earthquakes struck Romania (1977, 1986 and 1990). The August 17, 1999,Izmit-Kocaeli (Mw = 7.4) earthquake and the November 12, 1999, Düzce-Bolu (Mw = 7.1)earthquake were felt and recorded in Romania too. The purpose of this paper is a comparativestudy of these two events and the two major earthquakes that struck Romania in 1977 and1986. For this reason two horizontal components of records of the Romanian earthquakes havebeen analysed, together with some main records obtained during the Turkish strong motions.The main tools used in the comparative analysis are: the response spectra of strong motionrecords, the global parameters defined on this basis, which characterize an individualcomponent of a record and the response spectrum based frequency dependent intensityaveraged upon a frequency interval. The records obtained in Romania during the two Turkishevents (in Bucharest and in Focsani) are analised too.