THE EFFECT OF LOCAL SITE CHARACTERISTICS ON DYNAMIC SITE RESPONSE ANALYSES OF A MAJOR URBAN AREA: WARNINGS OF MODERATE SCALE EARTHQUAKES

摘要

The Western Anatolia is one of the major seismically active regions in Turkey. The city of Izmir, which is the third greatest city of the country, has been subjected to moderate scale earthquakes in long distances since April 2003. The 10.04.2003 Urla Earthquake (M = 5.6), the 17.10.2005 S?? gac?k Bay (Seferihisar) Earthquakes (M = 5.7 and M = 5.9), and the 21.10.2005 Uzunkuyu-Urla Earthquake (M = 5.9) are the most serious earthquakes causing some damage to medium-height buildings on alluvial soil deposits. However, the most recently occurred moderate scale earthquake in the city center was the 16.12.1977 Izmir Earthquake (M = 5.3).). In this study, the effect of local soil conditions on dynamic site response analyses in the northern coast of Izmir Bay Area has been investigated. The design spectrum for the northern coast of Izmir Bay area was developed by using strong motion records of the abovementioned close and long distance earthquakes and following the equivalent-linear method principles. While dynamic site-response analyses have been performed, it has been determined that the limits of spectrum defined in the Turkish Seismic Code has been accessed / exceeded for some alluvial regions of the city. Results of dynamic site-response and structural performance analyses on selected damaged building have been interpreted according to the national and international seismic codes.