Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

Evaluation Of Potential Landuse Of The Areas Between Avcilar And Esenyurt (Istanbul) By Using Geophysical Methods

17 August 1999 (Gölcük) İzmit and 12 November 1999 Düzce earthquakes also brought up the anxiety of possibility of occurrence of a big earthquake in İstanbul which is the most important city of Turkey with its industrial popularity density, historical and cultural background. Economical and social losses together with the life and property damages that may arise as a result of a big earthquake which shall occur in İstanbul will affect the whole country. İstanbul which is located in the first degree earthquake zone had experienced big earthquakes in its history. The requirement for the preparation of maps providing the information and parameters that shall expose the dynamic properties of regional soils and their possible behavior during earthquakes is quite important for the purpose of selection of location of buildings and other engineering structures and systems and their design to withstand against earthquakes in order reduce earthquake damages in İstanbul which is very important for Turkey.

If we explain that earthquake, local ground and structural properties are the factors affecting structural hazards in earthquakes then defining the dynamic properties of the Avcılar ground which is the most affected city of İstanbul at Gölcük earthquake on 17 August 1999, gains importance from geological point of view. Microtremor measuring, seismic measuring and drilling data have been used in defining the site characteristic period and soil amplification properties of Avcılar and Esenyurt municipal areas, in the content of this thesis. Nakamura method which is extensively used in field studies due to its easy application and reliable results is preferred in studies executed by using microtremor, based on its quick, economical and reliable results in the determination of site characteristic period and variation of soil amplification, particularly in the studies covering vast areas. Some evaluations are made related with soil amplification variation which is obtained from microtremor measuring, seismic measuring and drilling SPT-N data. The results obtained from this study consist of the determination of land application phases of Nakamura method, the site characteristic period and the soil amplification variation of Avcılar and Esenyurt municipal areas. Consequently the maps that are formed separately by using such parameters are compared.

It has been observed as a result of comparison of findings between drilling data and values calculated by other approaches that concordant results are obtained in connection with the local soil class corresponding to site characteristic period and soil amplification. With respect to the soil amplification values it has been seen that such values weren’t numerically equal and that they were different to a great extent in some points and they show a parallel variation to the soil amplification variations found in drilling. Similarly, it is seen that site characteristic period and soil amplification values calculated from microtremor measurements are also concordant with the geological map showing the geological units and that high site characteristic period and soil amplification values are obtained in the alluvial base of Haramidere, Gürpınar and Çukurçeşme formations which are faced at valley slopes and in Marmara Sea and Küçükçekmece coast, whereas low site characteristic period and soil amplification are found in the location of Bakırköy formation

FIRAT Osman ,

Danışman : Y.Doç.Dr.Oğuz GÜNDOĞDU

Anabilim dalı : Jeofizik Mühendisliği

Yılı : 2006

Tez savunma Jürisi : Y.Doç.Dr.Oğuz GÜNDOĞDU (Danışman)

Prof.Dr.Yıldız ALTINOK

Prof.Dr.Naci ORBAY

Doç.Dr.Hayrettin KORAL

Doç.Dr.Zuhal DÜZGİT