Tez Arşivi

Tez aramanızı kolaylaştıracak arama motoru. Yazar, danışman, başlık ve özetlere göre tezleri arayabilirsiniz.


İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / İnşaat Mühendisliği Anabilim Dalı

2014

33 katlı betonarme bir binanın deprem performansının zaman tanım alanında doğrusal elastik olmayan hesap yöntemi ile belirlenmesi

Seismic performance evaluation of 33 storey RC building by nonlinear time history analysis

Bu tez, YÖK tez merkezinde bulunmaktadır. Teze erişmek için tıklayın. Eğer tez bulunamazsa, YÖK Tez Merkezi'ndeki tarama bölümünde tez numarasını arayabilirsiniz. Tez numarası: 363876

Tezi Bul
Özet:

Ülkemizin aktif bir deprem bölgesi üzerinde yer alması ve son zamanlarda meydana gelen depremlerin ağır hasarlara ve can kayıplarına yol açması depreme dayanıklı yapı tasarımının gerekliliğini ve önemini göstermektedir. Bu sebeple günümüzde yapıların deprem davranışı ve hasar durumu hakkında daha detaylı bilgiler veren yaklaşımlar ve hesap yöntemleri Deprem Bölgelerinde Yapılacak Binalar Hakkında Yönetmelik (DBYBHY) 2007' de yer almıştır. Bu yönetmeliğin yedinci bölümünde deprem bölgelerinde bulunan mevcut ve güçlendirilecek tüm binaların ve bina türü yapıların deprem etkileri altındaki performanslarının değerlendirilmesinde uygulanacak hesap kuralları, güçlendirme kararlarında esas alınacak ilkeler ve güçlendirilmesine karar verilen binaların güçlendirme tasarımı ilkeleri yer almaktadır. Bu çalışma kapsamında doğrusal elastik olmayan davranış temel alınarak DHYBHY 2007 esasları çerçevesinde zaman tanım alanında doğrusal elastik olmayan hesap yöntemi kullanılarak mevcut betonarme çok katlı bir yapı irdelenecektir. Çalışmanın birinci bölümünde konu, amaç ve kapsam ikinci bölümünde çalışmanın temel kısımlarından birisi olan doğrusal olmayan davranış üzerinde durulmuştur. Bu bölümde doğrusal elastik olmayan malzeme modellerine değinilmiş ve plastik mafsal hipotezi hakkında bilgiler verilmiştir. Ayrıca depreme dayanıklı bina tasarımı başlığı altında süneklik kavramı ve kapasite tasarımı geniş olarak ele alınmıştır. Üçüncü bölümde performans kavramı ve DBYBHY 2007'nin yedinci bölümünde yer alan doğrusal elastik olmayan hesap yöntemleri kapsamında performans yaklaşımları belirtilmiştir. Verilen teorik bilgilerden sonra dördüncü bölümde sayısal örnek olarak ve çalışmanın ana konusunu oluşturan mevcut 33 katlı betonarme bir binanın deprem performansının zaman tanım alanında doğrusal elastik olmayan hesap yöntemi ile belirlenmesine geçilmiştir. Bu bölümde mevcut yapının genel bilgileri verilmiş, yükler belirtilmiş, yapılan kabuller ve hesap modelleri gösterilmiştir. Kullanılan programlar çerçevesinde yapısal modelleme aşaması ve analiz süreci şekiller yardımıyla açık olarak işlenmiştir. Bölümün sonunda çözümleme sonuçları yorumlanmış ve performans değerlendirmesi yapılmıştır. Son olarak sonuçlar ve öneriler kısmında tez çalışması genel olarak ele alınmış ve özellikle dördüncü bölüme konu olan sayısal inceleme kapsamında yapılan yaklaşımlar, kabuller ve kullanılan yöntemler irdelenmiş, ortaya çıkan sonuçlar belirtilmiş ve gerekli öneriler yapılmıştır.

Summary:

During the past two decades, many large-scale earthquakes have occurred consecutively around the world. These earthquakes resulted in hundreds of thousands of casualties and in significant economic damage. Based on the lessons learned from the earthquakes, seismic codes need to be upgraded. In the upgrading of the seismic codes, there are some topics as follows: • earthquake-resistant design of new reinforced concrete (RC) structures • evaluation of existing RC structures • developing new strengthening techniques for existing RC structures with insufficient earthquake resistance. For this purpose, performance based design and seismic evaluation techniques of existing RC structures have been developed rapidly. In the present days, many linear or nonlinear analysis methods are available for the performance based design and seismic evaluation of the existing structures. Since material and geometric nonlinearity are not considered in the linear analysis methods, these methods are easy to employ in the seismic evaluation of the structures but their results are not so reliable. There are two types of nonlinear analysis methods which are known as nonlinear static and dynamic analysis. The more realistic results can be obtained by employing the nonlinear static analysis methods if they are compared with linear analyses ones. On the other hand, nonlinear dynamic analysis method is the advanced method since it can be possible to monitor the real behaviour of the structures during earthquakes. The codes of earthquake is the most significant resource that can be used to build an earthquake-resistant building. According to their geographical location, their geological and sesimic characteristics that apply within the territory and local ground conditions, countries prepare regulations that includes the rules which must be followed during building design. For this purpose, a new Turkish Earthquake Code (TEC) is published in 2007 (Deprem Bolgelerinde Yapılacak Binalar Hakkkında Yonetmelik-DBYBHY ) with recent earthquake resistant building design principles. This regulation of the seventh chapter, in earthquake zones available and will be strengthened all the buildings and building structures under seismic effects in assessing the performance will be applied accounting rules, the strengthening in the decisions will be based on principles and strengthening decided buildings strengthen the design principles are included. Developments in structural engineering, computer technology and the material science help engineers to be familiar to the earthquake motions and the effects of earthquake on buildings in a more realistic and accurate way. These developments with the observation of the nonlinear behaviour of structural systems in an earthquake, enable engineers to accomplish more realistic designs. The performance of structural systems under earthquake effects can be determined by linear and nonlinear evaluation methods. The linear evaluation methods are based on strength and the nonlinear evaluation methods are based on deformation and displacement. According to the linear evaluation theory, it is assumed that the material is linear-elastic and the deformations are small, so that the principle superposition can be applied to the analysis. In the nonlinear evaluation approach, however, the behaviour of material beyond the linear elastic limit is considered; therefore the relationships are not linear. Consequently, the superposition principle cannot be applied in nonlinear analysis. In the scope of this thesis, seismic performance of a 33 storey existing reinforced concrete structure is evaluated by the nonlinear time history analysis method of Turkish Earthquake Code (TEC) 2007. The present master thesis is composed of five chapters. The first chapter is designated for the brief explanation of the subject. The aim and the scope of the study is explained in this part. In the second chapter of this study, nonlinear behavior and the analysis were given as the main portion of the study. In this context, nonlinear material models are expressed, the stress-strain relationships of various building materials have been analyzed, for the reinforced concrete section, moment-curvature curve properties and interaction surfaces were examined. Also a quite large information is given about the plastic hinge hypothesis. Again in this section, under the heading of earthquake-resistant building design, ductility and the capacity design concepts are widely discussed. The third chapter gives information on the performance based design and assessment of structures. İn this chapter, concept of performance and the nonlinear performance aproach of the TEC 2007 were explained. İnformation about the general principles of the nonlinear evaluation methods and the assumptions on which these methods are based on and also performance levels and performance assessment methods are given in this section. The fourth chapter is devoted for the numerical investigations. A three dimensional structural model of a 33 storey building is analyzed by a structral analysis program in nonlinear time history analysis method given by the TEC 2007. Then the performance level evaluation of the building structure with the nonlinear performance aproach method of TEC 2007. İn this section, firstly an information was given about the existing reinforced structure feautures which used in analysis model. Loads, seismic zone, material properties, type of structure and a lot of other properties of the building was described. Then for the nonlinear analysis, the plastic hinge properties of beams and columns were determined clearly. Shear walls were modeled with nonlinear layered shell elements for more accurate results. In this part furthermore, selection and scaling for real earthquake ground motion records are explained briefly. Also in this chapter, important data entry information used for nonlinear modeling of the structural components, load analysis and calculated plastic hinge properties and their assigns to the model for performance evaluation of the structural system were presented. The fifth chapter is the final chapter and is devoted to the results, conclusions and recommendations of the study. Main findings, the examination of the results of this study were explained in this chapter. The appendices was given the appendices chapter of this study. In this chapter, data information about the existing reinforced concrete building which used in study, cracked section properties which used in analysis model, some of the nonlinear time history analysis and the performance evaluation of the building results, and the comparing of the original and the matched earthquakes records and specturums were presented.