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The results of shake table tests on three concentrically-braced sub-frames are compared with a series of correlative inelastic analyses. Both transient time-history and nonlinear static (pushover) analyses are considered. The lateral resistance of the test frames is provided by a pair of cold-formed tubular steel members. The brace cross-section is varied between tests to investigate the influence of brace slenderness on the stiffness, resistance and ductility displayed by the frame under strong earthquake loading. Response simulations using a two-dimensional analytical model of the test frame are compared with the experimental results. Brace strengths and elastic test frame properties established in complementary static tensile tests and low-level shake table tests, respectively, are used to determine model input data. The transient acceleration and displacement response of the frames calculated in nonlinear time-history analyses are compared with corresponding experimental measurements. The base shear frame drift relationship is calculated using pushover analyses that consider either the resistance of both frame braces or the tension brace alone. These are compared with the experimental hysteretic response of the test frame. On the whole, the analytical results are observed to agree well with the experimental results, especially with respect to brace tension forces and frame base shear. Cases where the experimental and analytical responses deviate are identified and the implications for earthquake response assessment and design are discussed. peer-reviewed

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2007, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2007, Bu çalışmada, 2007 Türk Deprem Yönetmeliği’nde mevcut veya güçlendirilmiş binaların deprem performanslarının belirlenmesi amacıyla önerilen doğrusal elastik olmayan değerlendirme yöntemlerinden Artımsal Eşdeğer Deprem Yükü Yöntemi ve Zaman Tanım Alanında Hesap Yöntemi’nin karşılaştırılmasına yönelik olarak, bir parametrik sayısal inceleme gerçekleştirilmiş ve elde edilen sonuçlar değerlendirilmiştir. Sayısal incelemelere esas oluşturan taşıyıcı sistem modellerinin 1975 Türk Deprem Yönetmeliği’ne göre tasarımları yapılmış ve bunların beton dayanımı ve sargı etkisi açısından alternatifleri oluşturulmuştur. Sayısal incelemelerin sonuçları, 2007 Türk Deprem Yönetmeliği’nde önerilen doğrusal elastik olmayan yöntemlerden Artımsal Eşdeğer Deprem Yükü Yöntemi ve Zaman Tanım Alanında Hesap Yöntemi ile belirlenen kesit hasar bölgeleri ve bina tepe yerdeğiştirmelerinin, incelenen tüm taşıyıcı sistem modellerinde büyük oranda birbirine yakın sonuçlar verdiğini göstermektedir., In this thesis, a parametric earthquake performance evaluation study is performed, using the non-linear pushover and non-linear time history methods proposed by the 2007 Turkish Seismic Code and the numerical results obtained by these two methods are compared and discussed. For this purpose sample framed structures, six to ten stories high, are designed by the provisions of 1975 Turkish Seismic Code and alternative systems are created considering poor confinement and low concrete strength. The numerical results obtained by this study indicate that the nonlinear pushover and time history methods proposed by the 2007 Turkish Seismic Code exhibit similar results especially in terms of cross-sectional damage levels and roof displacements for all considered structural models., Yüksek Lisans, M.Sc.

Son on yılda yapıların dizaynının hedef deplasman veya deplasman profili için yapıldığı direkt deplasman esaslı dizayn metodu, birçok yapı tipinin dizaynı için kullanılmaktadır. Bu çalışmada moment aktaran çerçeve tipi yapılar için geliştirilen Direkt Deplasman Esaslı Dizayn (DDED) metodu perde çerçeve tipi yapıların dizaynı için genişletilmiştir. Perde çerçeve yapıların DDED'inin yapılabilmesi için perde çerçeve tipi yapılar ait lineer olmayan deplasman profilinin belirlenmesi gerekir. Bu nedenle, perde çerçeve tipi yapıların deplasman profillerinin elde edilmesi için DDED ve lineer olmayan dinamik analizin birlikte kullanıldığı iteratif bir yöntem önerilmiş ve bu yöntem kullanılarak sistemde tek bir perdenin kullanıldığı, çerçevenin ortasında olduğu, altı katlı yapı için lineer olmayan deplasman profilli elde edilmiştir. Ayrıca farklı perde yerleşiminin ve farklı açıklık sayısının deplasman profiline etkisi araştırılmıştır., Direct displacement based design that designs the structure for a given target displacement profile is used for the design of several types of structures in the last decade. In this study, the direct displacement based design (DDBD) method developed for the design of moment resisting structures is extended for the design of wall-frame type structures. Displacement profiles of the wall-frame type structures must be determined for the DDBD of wall frame structures. Therefore, an iterative method that uses DDBD and nonlinear time history analysis together is proposed for determining the displacement profiles. Displacement profiles for six storied four span wall-frame type structures that have one wall in the middle of the frame are determined. Also the affects of the location of the wall and the number of the span is investigated.

Deprem esnasında yapıda oluşan yapısal ve yapısal olmayan hasarlar genellikle sistemde oluşan yatay deplasmanlardan meydana gelmektedir. Günümüzde kullanılan geleneksel kuvvet esaslı dizayn metodunda deplasmanlar dizaynın sonunda kontrol edilirler. Bu nedenle potansiyel hasarların kontrol edilmesi çok güçtür. Yapıların hedef bir deplasman için dizayn edildiği deplasman esaslı dizayn yöntemi ile yapının hasar potansiyeli kontrol altında tutulabilmektedir. Deplasmanlar, direkt deplasman esaslı dizayn metodunun temelini oluşturmaktadır. Moment aktaran çerçeve tipi yapıların direkt deplasman esaslı dizaynı için iki farklı deplasman profili önerilmiştir. Bu çalışmada lineer olmayan dinamik analiz kullanılarak dört, altı ve on katlı moment aktaran çerçeve yapılar için deplasman profilleri elde edilmiştir.&nbsp, Damages that occur in structural and non-structural elements during the earthquakes are due to lateral displacements. Traditional force based design methods control displacements at the end of the design. Therefore, it is difficult to control potential damages. Direct displacement based design approach that designs the structure for a given displacement profile, can control the potential damages. Direct displacement based seismic design uses the displacement profile as the basis of the design approach. Two different displacement profiles proposed for the direct displacement based seismic design of moment resisting reinforced concrete frame structures. In this study displacement profiles for four, six and ten storey moment resisting frames are determined by using nonlinear time history analysis.

Balıkesir Üniversitesi, Fen Bilimleri Enstitüsü, İnşaat Mühendisliği Ana Bilim Dalı, Deprem esnasında yapıda oluşan yapısal ve yapısal olmayan hasarlar genellikle sistemde oluşan yatay deplasmanlardan meydana gelmektedir. Günümüzde kullanılan geleneksel kuvvet esaslı dizayn metodunda deplasmanlar dizaynın sonunda kontrol edilirler. Bu nedenle potansiyel hasarların kontrol edilmesi çok güçtür. Yapıların hedef bir deplasman için dizayn edildiği deplasman esaslı dizayn yöntemi ile yapının hasar potansiyeli kontrol altında tutulabilmektedir. Son on yılda yapıların dizaynının hedef deplasman veya deplasman profili için yapıldığı direkt deplasman esaslı dizayn metodu birçok yapı tipinin dizaynı için kullanılmaktadır. Bu çalışmada moment aktaran çerçeve tipi yapılar için geliştirilen Direkt Deplasman Esaslı Dizayn (DDED) metodu perde çerçeve tipi yapıların dizaynı için genişletilmiştir. Perde çerçeve yapıların DDED'ının yapılabilmesi için perde çerçeve tipi yapılar ait deplasman profilinin belirlenmesi gerekir. Bu nedenle, perde çerçeve tipi yapılatın deplasman profillerinin elde edilmesi için DDED ve lineer olmayan dinamik analizin birlikte kullanıldığı iteratif bir yöntem önerilmiştir. Tek bir perdenin, çerçevenin ortasında olduğu, altı, dokuz ve oniki katlı dört açıklıklı yapılar için lineer olmayan deplasman profilleri elde edilmiştir. Ayrıca farklı perde yerleşiminin ve farklı açıklık sayısının deplasman profilini etkilemediği belirlenmiştir. Lineer olmayan deplasman profillerinin elde edildiği son iterasyon adımında yapılar gerçek deplasman profili kullanılarak DDED metoduna göre dizayn edilmektedir. DDED metodunun performans değerlendirmeleri lineer olmayan dinamik analiz ile elde edilen eleman süneklik seviyelerine göre yapılmıştır. Perde- çerçeve tipi yapılar için önerilen DDED metodunun yapıların lineer olmayan davranışının da metoda dahil edildiği etkili bir metot olduğu görülmüştür. Ayrıca bu çalışmada yapılar kuvvet esaslı dizayn metodu kullanılarak dizayn edilmişler ve kuvvet esaslı dizaynda kullanılan yapı davranış katsayısı irdelenmiştir., Damages that occur in structural and non-structural elements during the earthquake are due to lateral displacements. Traditional force based design methods controls displacements at the end of the design. Therefore it is difficult to control potential damages. Displacement based design approach that designs the structure for a given target displacement or displacement profile can control the potential damages. Direct displacement based design that designs the structure for a given target displacement profile is used for the design of several types of structures in the last decade. In this study, the direct displacement based design (DDBD) method developed for the design of moment resisting structures is extended for the design of wall-frame type structures. Displacement profiles of the wall-frame type structures must be determined for the DDBD of wall frame structures. Therefore, an iterative method that uses DDBD and nonlinear time history analysis together is proposed for determining the displacement profiles. Displacement profiles for six, nine and twelve storied four span wall-frame type structures that have one wall in the middle of the frame are determined. Its determined that location of the wall and the number of the span of the system do not change the displacement profile of the wall frame system. Structures whose nonlinear displacement profiles are determined in the last iteration step are the structures that were designed for the real displacement profile. Performance of DDBD method is evaluated by using ductility levels of the elements that are determined from nonlinear time history analysis. It is seen that the DDBD method proposed for the design of wall frame type structures is an effective method that incorporates the inelastic behavior of the structure to the method. Also in this study the structures are designed by using force-based design and structural response coefficient that is used in force-based design is investigated.

V ÖZET Ülkemizdeki sanayi bölgelerinin %98'i yüksek deprem riski taşıyan alanlarda konumlandırılmıştır. Bu sanayi bölgelerindeki fabrikaların hemen hepsi de, büyük açıklıkları kolonsuz olarak geçmek için ideal bir çözüm olan `tek katlı mafsal bağlantılı prefabrike yapılar` olarak inşa edilmişlerdir. Ancak bu yapıların deprem davranışı konusundaki bilgi düzeyimiz ve araştırmalar henüz yeterli seviyelerde değildir. Bu çalışmada 1998 deprem yönetmeliğine göre tasarlanmış tek katlı prefabrik sanayi yapılarının deprem davranışı statik itme analizi (pushover) ve doğrusal ötesi zaman tanım alanında analiz (time-history) yöntemleri kullanılarak SAP2000 programıyla incelenmiş ve Deprem Yönetmeliğinin yeterliliği araştırılmıştır. Statik itme analizi sonucu bulunan kapasite eğrisiyle depremin talebi arasındaki ilişki ve yapının performans noktası Kapasite Spektrumu Yöntemi ile elde edilerek, sonuçlar doğrusal ötesi zaman tanım alanında analizden bulunan sonuçlar karşılaştırılmıştır. Tüm bu çalışmalar sonucunda hem deprem yönetmeliği 'ne bazı eleştiriler getirilmiş hem de Kapasite Spektrumu Yönteminin sonuçları sorgulanmıştır. Anahtar Kelimeler: Prefabrik Yapı, Statik İtme Analizi, Doğrusal Ötesi Zaman Tanım Alanında Analiz, Kapasite Spektrumu Yöntemi, Deprem Yönetmeliği Salih YILMAZ VI ABSTRACT In Turkey, %98 of the industrial regions, are located on high risk earthquake zones. Hinge connected precast concrete structures are ideal solutions to build factories, which need open spaces without columns and many buildings in these industrial regions are constructed using this type of construction. However, behavior of pin connected precast concrete structures under earthquake loading needs more research. In this study, first, some type of one story precast concrete structures having pin connected beams are designed according to Turkish Earthquake Code (1998 version). These buildings, then, are analyzed by SAP200 using static pushover and nonlinear time-history analysis techniques and adequacy of Turkish Earthquake Code is investigated. By the way, results of the capacity spectrum method and nonlinear time history analysis are compared with each other. As a result of this study, Turkish Earthquake Code and results of the capacity spectrum method are criticized. Keywords: Precast building, static pushover analysis, nonlinear time history analysis, capacity spectrum method, earthquake code Salih YILMAZ 158

Over the last decade the amount of population injured by accident furniture overturning is increased and this trend is expected to continue. Non anchored body motion can be categorized in 6 basic types: rest, slide, rock, slide-rock, free flight and impact. The aim of this research is to analyze through numerical analysis the behavior of a free-standing rigid body during the phase of rocking motion under dynamic load. The model of free body rocking motion was proposed by G. W. Housner in 1963 first. Later a number of alternative models have been developed opportunely change the original assumption in order to and obtain more realistic results. In this research different models are compared with numerical simulations, using different excitation input and results are shown in the acceleration-frequency plane. These results confirmed the importance of the geometrical shape of the rigid block and the necessity to individuate the risk factors that can cause overturning phenomena. Nonlinear time history analysis using real earthquake floor motions recorded in a real time monitored building in California are used to simulate the behavior of a furniture located inside a multi-story building. Sensitivity analysis is performed in order to find the optimal location of the furniture inside the building. The research goal is to establish how to reduce the risk of overturning during an earthquake in real structures and to propose a simple and practical procedure to locate the risk area in the building where slender furniture can overturn. Prevention actions are proposed by changing the shape of the furniture, the friction coefficient or by using some appropriate devices

This paper investigates the response of nonstructural components in the presence of nonlinear behavior of the primary structure using floor response spectra method (FRS). The effect of several parameters such as initial natural frequency of the primary structure, natural frequency of the nonstructural components (subsystem), strength reduction factor and hysteretic model have been studied. A database of 164 registered ground acceleration time histories from the European Strong-Motion Database is used. Results are presented in terms of amplification factor and resonance factor. Amplification factor quantifies the effect of inelastic deformations of the primary structure on subsystem response. Resonance factor quantifies the variation of the subsystem response considering the primary structure acceleration. Obtained results differed from precedent studies, particularly for higher primary structure periods. Values of amplification factor are improved. Obtained results of resonance factor highlight an underestimation of peak values according to current design codes such as Eurocode 8. Therefore a new formulation is proposed.

The latest developments in the construction technologies and the materials facilitated the practicing engineers to go higher and energy-efficient buildings. However, the safety of the buildings and the residents has been an issue all the time. This is not an exception for the precast structures. The advantages of the precast elements are the quality assurance and the rapid erection on the site and challenged by the connection details and their performances during the extreme loading cases such as earthquakes. The utilization of a special mechanical connection of the precast members have been in the focus of the recent works in Istanbul Technical University (ITU-STEELAB). The prototypes of the proposed special connectors, called as cushion, were tested in STEELAB in order to determine the mechanical properties such as lateral and axial stiffness and the failure modes. Once the properties were determined, a hypothetical building of single story multi-bay slab type structure was modeled in the computer framework capable of substituting various parametric values into the model, processing and extracting the results for statistical analysis, SAMA. SAMA is developed based on the use of SAP 2000 OAPI functions called in MATLAB and Python scripts. In the hypothetical model, the cushions were modeled as link elements and placed between all the precast elements including foundation-cladding interface. Extensive non-linear time-history analysis was conducted to identify the damage localization by comparing the energy dissipation at each mechanical connector under ground motion records selected according to focal distance, site conditions and intensity. The preliminary results reveal that the cushions are effectively dissipating a significant amount of energy and mitigating the collapse of the precast elements. The more detailed conclusions will be discussed in the near future. Publisher's Version

Displacement-based design (DBD) methods are emerging as the latest tools for performance-based seismic design and as a viable alternative to conventional force-based design method (FBD). FBD starts with an estimation of base shear force, which is calculated based on the fundamental period and ductility capacity of the structure. This base shear force is distributed to the various floor levels based on the fundamental mode shape, and the structure is designed for these lateral loads. Unlike FBD, DBD method requires explicit consideration of displacements. Typically, DBD determines a target displacement demand and then calculates the required base shear capacity to achieve this demand. In this method, the lateral loads at various floor levels are obtained based on an assumed inelastic displacement profile. This paper presents the findings of a study that uses the FBD method and DBD method to design a typical four-storeyed and a nine-storeyed regular frame. The performances of the frames were assessed using nonlinear time history analysis and their relative performances are reported.

In order to meet desired seismic performances, it is increasingly evident that engineers require reliable methods for the estimation of seismic demands on both structural and non-structural elements. To this end, current design codes incorporate simplified methods for the prediction of acceleration demands on secondary structural and non-structural elements for buildings with fixed bases. However, no guidance is currently provided as to how to estimate the seismic demand on nonstructural elements in base isolated structures. In such structures, large floor accelerations may still be recorded, particularly in the case of higher mode interactions or horizontal-vertical coupling effects. In all cases, determining the seismic demand on non-structural elements is necessary in order to be able to perform a rational design of those elements, and to be able to effectively control their seismic response. In order to take a step towards the formation of accurate yet simplified methods of predicting peak floor accelerations and floor spectra in base isolated structures, this analytical work examines the response of a number of base isolated case study structures subjected to a series of ground motions of varying intensity. The results of the non-linear time history analyses are used to identify the factors that appear to affect the shape and intensity of acceleration demands on secondary structural and non-structural elements.