P25 Ve Durtes Öndeğerlendirme Yöntemleri Ve 1999 Düzce Depreminde Hasar Görmüş Binalara Uygulanması

Abstract

Özellikle Türkiye gibi deprem kuşağı üzerinde olan ülkeler için mevcut yapıların deprem performanslarının belirlenmesi gerekliliği tartışılamaz derecede mühimdir. Bu ihtiyaç doğrultusunda TDY’07’de yer alan “Mevcut Yapıların Değerlendirilmesi” bölümü eklenmiştir. Bu bölümde doğrusal elastik ve doğrusal elastik olmayan yöntemler yer almaktadır. Fakat yapı stoğunun, çok zamanın kısa ve maddi kaynakların kısıtlı olduğu durumlarda yönetmelikte yer alan ayrıntılı analiz yöntemlerinin uygulanması imkansızdır. Bu durumda stoktaki yapıların, hızlı sonuçlar veren can kaybına sebep olabilecekleri ayıklayan ön değerlendirme yöntemi ihtiyacı doğmuştur. Dünyada bu amaca yönelik birçok ön değerlendirme yöntemleri geliştirilmiştir. Bu çalışmada ise ülkemizde geliştirilen öndeğerlendirme yöntemlerinden DURTES ve P25 yöntemleri incelenmiştir. Çalışmadaki amaç, P25 ve DURTES yöntemlerinin gerçek yapılara uygulanarak, birbirleri ve TDY Bölüm 7’de doğrusal elastik yöntemlerden olan “Eşdeğer Deprem Yükü Yöntemi” sonuçları ile karşılaştırılmasıdır. Altı bölümden oluşan çalışmanın birinci bölümünde giriş, çalışmanın amacı ve kapsamı verilmektedir. İkinci bölümde DBYBHY’07’deki “Mevcut Yapıların Değerlendirilmesi” kapsamında yer alan değerlendirme yöntemleri ve dünya ve ülkemizde kabul görmüş diğer ön değerlendirme yöntemleri kısaca açıklanmıştır. Üçüncü bölümde DURTES yöntemine ait tanımlamalar ve hesap adımları ayrıntılı olarak verilmektedir. Dördüncü bölümde P25 yöntemi ayrıntılı olarak açıklanmıştır. Beşinci bölümde ise sayısal incelemelere yer verilmiş olup Düzce depremi yaşamış 17 adet gerçek binaya DURTES ve P25 yöntemi uygulanmış, aralarından seçilen bir binanın ise TDY’ne göre ayrıntılı analizi yapılmıştır. “Sonuç ve Öneriler” kısmında çalışmada elde edilen sonuçlar tartışılarak birbirleri ile karşılaştırılmıştır.

An earthquake is the result of sudden release of energy in the Earth’s crust of that creates seismic waves. The seismicity, seismism or seismic activity of an area to refers to the frequency, type and size of earthquake experienced over a period of time. Earthquakes are measured using observations from seismometers .The moment magnitute is the most common scale on which earthquakes larger than approximately 5 are reported for the entire globe. The more numerous earthquakes smaller than magnitude reported by national seismological observatories are measured mostly on the local magnitude scale, also referred to as the Richter scale. These two scales are numerically similar over their range of validity. Magnitude 3 or lower earthquakes are mostly almost imperceptible and magnitude 7 and over potentially cause serious damage over large areas, depending on their depth. The largest earthquakes in historic times have been of magnitude slightly over 9, although there is no limit to the possible magnitude. The most recent large earthquake of magnitude 9.0 or larger was a 9.0 magnitude earthquake in Japan in 2011 (as of March 2011), and it was the largest Japanese earthquake since records began. Turkey is a seismically active area within the complex zone of collision between the Eurasian Plate and both the African and Arabian Plates. Much of the country lies on the Anatolian Plate, a small plate bounded by two major strike-slip fault zones, the North Anatolian Fault and East Anatolian Fault. The western part of the country is also affected by the zone of extensional tectonics in the Aegean Sea caused by the southward migration of the Hellenic arc. The easternmost part of Turkey lies on the western end of the Zagros fold and thrust belt, which is dominated by thrust tectonics. Seismic hazard in Turkey is highest along the plate boundaries, but there is a significant risk of damaging earthquakes almost anywhere in the country. Some of massive earthquakes in Turkey are given as; September 10 1509 İstanbul 7.2 Mw, February 23 1653 İzmir 7.5, August 17 1668 Anatolia 8, July 10 1688 İzmir 7 MS, February 28 1855 Bursa 6.7, June 2 1859 Erzurum 6.1 MS, April 3 1881 Cesme 7.3 Mw, April 29 1903 Malazgirt 6.7 MS, August 9 1912 Müfrete 7.3 MS, October 4 1914 Burdur 6.9 MS, September 13 1924 Horasan 6.8 MS, October 22 1926 Kars 6.0 MS, March 31 1928 İzmir 6.5 MS, May 18 1929 Suşehri 6.1 MS, May 7 1930 Hakkari 7.5MS, January 4 1935 Erdek 7.4 MS, April 19 1938 Kırşehir 6.6Ms, September 22 1939 Dikili 6.6Ms, December 26 1939 Erzincan 7.8 MS, November 15 1942 Bigadiç 6.1 MS, December 20 1942 Erbaa 7.0, June 20 1943 Hendek 6.6 MS, November 26 1943 Ladik 7.4, February 1 1944 Gerede 7.5, October 6 1944 Ayvalık 6.8 MS, August 17 1949 Karlıova 6.8, August 13 1951 Kurşunlu 6.9, March 18 1953 Yenice 7.2 MS, July 16 1955 Söke 6.8 MS, April 25 1957 Fethiye 7.1 MS, May 26 1957 Abant 7.1, October 6 1964 Manyas 7.0 MS, August 19 1966 Varto 6.7, July 22 1967 Mudurnu 7.2, September 3 1968 Bartın 6.5 MS, March 28 1969 Alaşehir 6.5 MS, March 28 1970 Gediz 7.2 MS, May 22 1971 Bingöl 6.9, September 6 1975 Lice 6.6 MS, November 24 1976 Muradiye-Çaldıran 7.5 MS, October 30 1983 Erzurum 6.9 MS, March 13 1992 Erzincan 6.8, October 1 1995 Dinar 6.1 MS, June 27 1998 Adana-Ceyhan 6.2 MS, August 17 1999 İzmit 7.6, November 12 1999 Düzce 7.2M, February 3 2002 Afyon 6.5 Mw, January 27 2003 Pülümür 6.1 Mw, May 1 2003 Bingöl 6.1 Mw, March 8 2010 Elazığ 6.1 Mw, April 19 2011 Kütahya 5.8 Mw, October 23 2011 Van 7.2 Mw. Considering the pass recordings of earthquakes, the massive and devastating earthquakes are recorded in Turkey and it confirms that Turkey is in active earthquake zone. Latest event of massive earthquake is the 1999 Duzce Earthquake. An earthquake of moment magnitute 7.1 has taken place to the immediate south of the Duzce, a town of population 80.000.The earthquake took place along the Duzce Fault. As such except its timing, it was no surprise. It actually could have been considered as one of the segments of Aug.17 earthquake if it were the rapture in succession with the Aug.27 earthquake phenomenon. First and preliminary findings indicate fault rapture a fault 30 km with predominantly righ lateral offsets. Right lateral strike slip rapture between Duzce and Bolu. The offsets, reported to be about 1.5at Duzce (west end) reach up to 3m at towards Bolu (east end). The extensive damage is at Duzce, Kaynasli, Bolu, Akcakpca, Zonguldak, Adapazari. Most of the damage is concentrated in Kaynasli a small town on the main highway between Duzce and Bolu. Loss of life in Duzce seems to concentrate in few collapsed buildings that were “lightly” damaged in the August 17 earthquake, superficially repaired and later inhabited. Loss of life is somewhat limited since the buildings damaged in the August 17 earthquake were already vacated. Total number of heavily damaged buildings is in the vicinity of 200.550 people lost their lives and over 3000 people were hospitalized with injuries. Composing the design codes that have essential design criteria are have vital importance for our country that has active seismic belts and many earthquakes in the past. But it is impossible and unnecessary to demolish all existing buildings for cities like İstanbul that has billion building stock. In this case assessment of existing buildings is ensued. Many international and national codes are available that have detailed calculation for assessment of existing buildings. In our country, “Turkish Earthquake Code 2007” Section 7 has material and all calculation detail for assessment and reinforcement detail.. The seismic assessment of existing buildings is extremely important for the countries which are located on seismic belts such as Turkey. The section 7 “The Assessment of Existing Buildings” of Turkish Earthquake Code was added for this necessity. Nonlinear and linear elastic methods are available in this section. But it is impossible to assess the all stocks by using these detailed methods in limited time with limited financial resource. In this case, rapid assessment methods needed which can quickly eliminate the buildings that have high collapse risk. Many methods were developed for this requirement in the world. DURTES and P25 are two of these methods in our country. The purpose of this study is to perform DURTES and P25 methods on 17 existing buildings and perform “linear elastic method” on one of these buildings and to compare the results. These 17 buildings located in Duzce and experienced November 12 1999 Duzce Earthquake. All of them were exposed massive earthquake loads. Nine (9) of buildings are collapsed, five (5) of them are heavy collapsed and three (3) of them are medium damaged. At first these buildings were labeled as XXX-YYY-Y-XX-YY. The first “XXX” is symbolized the row of all buildings number, the second “YYY” is symbolized the three letter of city that is buildings are located on, the third “Y” is symbolized the type of carrier system such as R is reinforced, P is prefabricate and O is the other types, The fourth “XX” is symbolized the number of story and fifth “YY” is symbolized the stage of damage. Such as “CL” collapsed, “HD” heavy damage, “MD” medium damage, “SD” slightly damage, “ND” none damage and “NS” no seismicity. After the labeling, DURTES and P25 were performed on all buildings and one building was assessed by Section 7 of Turkish Earthquake Code. The thesis is consist of six section and the firs one includes the introduction and the aim and scope of the study. In the second section “Assessment methods of existing buildings” of Turkish Earthquake Code and the scoring methods that are accepted in the world and our country are explained. DURTES method is explained comprehensively in the third section. In the fourth section P25 method is explained detailedly. The fifth chapter presents the seismic performance evaluation of 17 reinforced concrete buildings with P25 and DURTES scoring methods and one of them Linear Elastic Method. At the last section, obtained results of these three methods were discussed and compared.