Himmet KARAMAN, Muhammed ŞAHİN

Zeytinburnu ilçesi için deprem hasar tahmini çalışması

İstanbul’da gerçekleşmesi beklenen depreme, en iyi şekilde hazırlanmak için afetin hangi bölgeleri, hangi tipteki yapıları en çok etkileyeceği ve bu afetin nasıl bir ekonomik bilanço çıkaracağını afet olmadan önce tahmin etmek gerekmektedir. Bu mekanizma dünya üzerinde deprem için sıklıkla kullanılmakta ve tatmin edici sonuçlar vermektedir. Hasar tahmini için en önemli bileşen, ilgili bölgedeki tüm olası senaryoları uygulayabilecek ve bu senaryoların ilgili bölge yapıları üzerindeki etkilerinin görülmesini sağlayacak ve bu etkilerin azaltılması için gerekli güçlendirmeleri önerecek bir yazılımlar bütünüdür. Çalışmanın amacı, İstanbul için deprem nedeniyle olası mevcut ve güncellenen riskleri ortaya koymak ve karar vericilere riski ortadan kaldırmak ya da azaltmak için geliştirecekleri zarar azaltma stratejilerinde yardımcı olabilecek güncellenen veri ve yöntemlere göre kendini yenileyebilen bir yazılım geliştirmektir. HAZUS ve MAEviz Amerika’da ulusal düzeyde kullanılan programlardır ve doğal afetlerin insan yaşamına uzun dönem sosyal ve ekonomik etkilerini azaltmada etkin bir rol oynamaktadırlar. Çalışma kapsamında geliştirilen HAZTURK adlı yazılım da bu sistemler gibi depremin toplum üzerindeki fiziksel, sosyal ve ekonomik sonuçlarını tahmin ve analiz eder. Çalışma kapsamında yapılan uygulamada pilot bölge olarak Zeytinburnu ilçesi seçilmiş ve mevcut bina verileri kullanılarak deprem hasar analizi yapılmıştır. Oluşturulan envanterin hasar görebilirlikleri (kırılganlık) saha çalışmaları ile parametrik kırılganlık metodu kullanılarak belirlenmiş ve oluşturulan hasar tahmin yazılımı kullanılarak tüm bina verilerine ait olası deprem sonrası yapısal ve ekonomik kayıplar belirlenmiştir.

Earthquake loss assessment study for Zeytinburnu district

After the 1999 earthquakes hit Kocaeli and Düzce, several seismic loss assessment studies were performed for the city of Istanbul; many of them were carried out by the most important academicians in Turkey. However, due to the rapid changes in the exposed inventory of the city, those studies were losing accuracy. This paper presents a seismic loss assessment system that can easily reanalyze earthquake scenarios including updates in the exposed inventory. This software can be used by the government decision makers and disaster management agencies. In the analysis described in this paper, the inventory data for the Zeytinburnu District is updated and visualized by using the rapid visual screening of buildings. Results from a loss assessment for the Zeytinburnu District are presented and compared with the results from previous studies. The loss assessment analysis for this study provide estimates of building damage, retrofit cost and economic loss. The increasing interest in computer-based seismic risk and loss assessment systems imposes new research requirements on the earthquake engineering community. Such systems are being used for the important purposes of disaster response planning and formulating risk reduction policies. Their accuracy and reliability are therefore fundamental to the success of these mitigation measures. The ingredients of seismic loss assessment are hazard, vulnerability or fragility, inventory and integrated visualization (losses). Assessment of the effects of such an earthquake in Istanbul to the buildings, substructures and transportation networks will help excessively in the preparation stage before the disaster. It is obvious that the expected earthquake for the Istanbul will cause inescapable and irreversible consequences for human life and economy of the country. That is why, it should be estimated that which regions will be affected more, which structures will have more damage, and what will be the economic losses after the disaster, to be prepared as good as possible to the expected earthquake. This kind of estimation will help on preparedness for the earthquake, mitigation, early and rapid response stages after the disaster, and recovery phases of the disaster management progress. This estimation methodology is being used on all over the world and giving very convincing results on earthquake cases. The most important component for the loss estimation is a kind of software that can realize all possible earthquake scenarios for the region of interest and provide the results of the affects of those scenarios on the region and offer reinforcements to mitigate the consequences of the disaster. This study based on MAEViz, a multipurpose risk assessment tool recognized by FEMA and supported by NSF in the United States and HAZUS, FEMA’s multi-hazard risk assessment tool. This new tool for Turkey comprehensively addresses all aspects of risk assessment and provides “out of the box” analysis. In this study, Zeytinburnu district was chosen as the pilot region and following the development of the system, applied for the Istanbul. The goal of this study is to introduce the current and updated risks because of the earthquake possibility in Istanbul and help the decision makers by developing a living system which, can be updated as the inventory of the region of interest and the methodology for the loss assessment updates itself. By this way it can help the decision makers on eliminating or reducing the risks. In the loss assessment process, the accuracy of the estimation is directly connected to the accuracy and the correctness of the inventory. That is why; the inventory for such an assessment study must be accurate and current. For this study, the damage and losses to be assessed can be listed for the buildings. The first step of the study was to establish an up-todate and accurate dataset for a region like Istanbul having an outdated and limited data on buildings and perform loss estimation over the established inventory. That is why the Zeytinburnu district was chosen as the pilot study region. The fragilities of this inventory were determined by field surveying and the parametrized fragility method. Loss estimation on the building and utility network data were made using HAZTURK, the developed loss estimation software to determine the post-earthquake structural damage and economic losses. The most important aspect of the software is to enable all possible earthquake scenarios to be analyzed having tools and menus in Turkish. HAZTURK is specifically designed to meet the needs of practitioners and researchers in Turkey with a user-friendly system.

PDF

___

Bibbee, A., Gonenc, R., Jacobs, S., Konvitz, J., Price, R. (2000). Economic effects of the 1999 Turkish Earthquakes: An Interim Report, Technical Report, Organization for Economic Cooperation and Development, Economics Department Working Papers No. 247, June 26, Paris.
Boore, D. M. ve Atkinson, G. M. (2006). Provisional empirical ground-motion model for the average horizontal component of PGA, PGV and SA at Spectral Periods of 0.05, 0.1, 0.2, 0.3, 0.5, 1, 2, 3, 4 and 5 Seconds, NGA Technical Report Version 1.70, PEER Center, Berkeley.
Boore, D. M., Joyner, W.B., Fumal, T.E., (1997). Equations for estimating horizontal response spectra and peak acceleration from Western North American Earthquakes: A summary of recent work, Seismological Research Letters, 68, 128-153.
Campbell, K.W. ve Bozorgnia, Y., (2006). Ground motion model for the average horizontal component of PGA, PGV, PGD and SA at selected spectral periods ranging from 0.01-10.0 seconds, NGA Technical Report Version 1.1, PEER Center, Berkeley.
Chiou, B.S.-J. ve Youngs, R.R. (2006). PEER-NGA empirical ground motion model for the average horizontal component of peak acceleration and pseudo-spectral acceleration for spectral periods of 0.01 to 10 seconds, Interim Report for USGS Review.
Chiou, B.S.-J. (2003). New hazard assessment product: Next generation of attenuation model (NGA), 2003 PEER Annual Meeting, Palm Springs, U.S.
Elnashai, A.S., (2007). Kişisel Görüşme.
Elnashai, A.S., Hampton, S., Karaman, H., Lee, J.S., McLaren, T., Myers, J., Navarro, C., Sahin, M., Spencer, B., Tolbert, N. (2008). Overview of applications of MAEviz-Istanbul – HAZTURK- 2007”, Journal of Earthquake Engineering, 12, 2, 100-108.
Federal Emergency Management Agency. (1999). HAZUS Earthquake Loss Estimation Methodology: User’s Manual, Federal Emergency Management Agency, Washington DC.
Federal Emergency Management Agency (FEMA- 154). (2002). Rapid Visual Screening of the Buildings for Potential Seismic Hazards Handbook, Earthquake Hazard Reduction Series.
Gazetas, G., Kallou, P.V. ve Psarropoulos, P.N., (2002). Topography and soil effects in the Ms 5.9 Parnitha (Athens) Earthquake: The case of Adames, Natural Hazards, 27, 133-169.
Griffiths, J.H.P., Irfanoglu, A., Pujol, S., (2007). Istanbul at the threshold: An evaluation of the seismic risk in Istanbul, Earthquake Spectra, 20, 1, 63-75.
Istanbul Metropolitan Municipality Construction Directorate Geotechnical and Earthquake Investigation Department, (2003). Earthquake Master Plan for Istanbul, Technical Report, Istanbul.
Jeong, S-H. ve Elnashai, A.S., (2006). New threedimensional damage index for RC buildings with planar irregularities, Journal of Structural Engineering, 132, 9, 1482-1490.
Japan International Cooperation Agency (JICA) and Istanbul Metropolitan Municipality (IMM), (2002). The study on a disaster prevention/mitigation basic plan in Istanbul including seismic microzonation in the Republic of Turkey, Final Report, Istanbul.
Kalkan, E. ve Gülkan, P. (2004). Emprical attenuation equations for vertical ground motion in Turkey, Earthquake Spectra, 20, 853-822.
Kandilli Observatory and Earthquake Research Institute (KOERI), (2003). Earthquake risk assessment for Istanbul metropolitan area, Bogazici University, Department of Earthquake Engineering, Final Report, Istanbul.
Karaman, H., Sahin, M., Elnashai, A.S., Pineda, O. (2008). Loss assessment study for Zeytinburnu district of Istanbul using MAEviz-ISTANBUL (HAZTURK), Journal of Earthquake Engineering, 12 ,2, 187-198.
Küçükçoban, S., (2004). Development of a software for seismic damage estimation: Case studies, Doktora Tezi, ODTÜ Fen Bilimleri Enstitüsü, Ankara.
Ozbey, C., Sari, A., Manuel, L., Erdik, M., Fahjan, Y., (2004). An empirical attenuation relationship for Northwestern Turkey ground motion using a random effects approach, Soil Dynamics and Earthquake Engineering, 24, 115-125.
Sadigh, K., Chang, C.Y., Egan, J.A., Makdisi, F., Youngs, R.R., (1997). Attenuation relationships for shallow crustal earthquakes based on california strong motion data, Seismological Research Letters, 68, 180-189.
Ulusay, R., Tuncay, E., Sönmez, H., Gökçeoğlu, C., (2004). An attenuation relation based on turkish strong motion data and iso-acceleration map of Turkey, Engineering Geology, 74, 265-291.
Yakut, A., Özcebe, C., Yücemen, M.S., (2006). Seismic vulnerability assessment using regional emprical data, Earthquake Engineering and Structural Dynamics, 35, 1187-1202