There are many advantages of masonry construction like widespread geographic availability in many forms, colors and textures, comparative cheapness, fire resistance, thermal and sound insulation, durability, etc. For such reasons, it is still a commonly used type of residential construction in rural and even in urban regions. Unfortunately, its behavior especially under the effect of earthquake ground motions has not been identified clearly because of its complex material nature. Hence, the masonry buildings with structural deficiencies belong to the most vulnerable class of structures which have experienced heavy damage or even total collapse in previous earthquakes, especially in developing countries like Turkey. This necessitates new contemporary methods for designing safer masonry structures or assessing their performance. Considering all these facts, this study aims at the generation of a new performance-based technique for unreinforced brick masonry structures. First, simplified formulations are recommended to estimate idealized capacity curve parameters of masonry components (piers) by using the finite element analysis results of ANSYS and regression analysis through SPSS software. Local limit states for individual masonry piers are also obtained. Then, by combining the component behavior, lateral capacity curve of the masonry building is constructed together with the global limit states. The final step is to define seismic demand of the design earthquake from the building through TEC2007 method. By using this simple technique, a large population of masonry buildings can be examined in a relatively short period of time noting that the performance estimations are quite reliable since they are based on sophisticated finite element analysis results.

In this study, Bah&ccedil / elik Dam, which is located in Kayseri Province, is investigated by means of horizontal movement due to reservoir loading and seepage inside the core and body. Two dimensional plain strain finite element analyses are carried out in order to find total stresses, displacements and pore water pressures. Mohr-coulomb soil model is used to represent elastic behavior of rock-fill material. Since there is no information about material used in dam body, material parameters are determined by sensitivity analyses being in the range of data acquired from literature survey. Calculated displacement and pore water pressures are compared to the data taken from field survey on actual dam body. As a conclusion remark, it is beleived that the horizontal displacement behaviour of two systems, such as real dam and computer modelling, would not match excatly since the materials used in real dam body would behave as plastic whereas that used in computer modelling assumed to be elastic.

Modular construction is a relatively new technique where prefabricated units are assembled on-site to produce a complete building. Due to detailing requirements for the assembly of the modules, these systems are prone to undesirable failure mechanisms during large earthquakes. Specifically, for multi-story Modular Steel Buildings (MSBs), inelasticity concentration in vertical connections can be an area of concern. Diaphragm interaction, relative displacements between modules and the forces in the horizontal connections need to be investigated. In this study, two 4-story MSBs with two different structural configurations were chosen to be analyzed. In the first model which was introduced in a study by Annan et al. (2009 a), some of the unrealistic detailing assumptions were challenged. To have a more accurate assessment of the structural capacity, in the second model, a more realistic MSB model was proposed. Using OpenSees, Incremental Dynamic Analyses (IDA) have been performed and conclusions were made.

Modular construction is a relatively new technique where prefabricated units are assembled on-site to produce a complete building. Due to detailing requirements for the assembly of the modules, these systems are prone to undesirable failure mechanisms during large earthquakes. Specifically, for multi-story Modular Steel Buildings (MSBs), inelasticity concentration in vertical connections can be an area of concern. Diaphragm interaction, relative displacements between modules and the forces in the horizontal connections need to be investigated. In this study, two 4-story MSBs with two different structural configurations were chosen to be analyzed. In the first model which was introduced in a study by Annan et al. (2009 a), some of the unrealistic detailing assumptions were challenged. To have a more accurate assessment of the structural capacity, in the second model, a more realistic MSB model was proposed. Using OpenSees, Incremental Dynamic Analyses (IDA) have been performed and conclusions were made.

At the design stage, column-beam connections of steel structures are assumed as fully rigid or as hinges, and the design is completed with these assumptions. On the other hand, in practice, steel column-beam connections show neither fully rigid nor fully hinge behaviour, and the characteristic behaviour of the connections lies between these two special cases. Performing realistic calculation of these forces and knowing the behaviour of structures close to reality will decrease life and goods losses to the minimum level in a probable of earthquake to be encountered in the future. &nbsp / In this study, seismic performance of 2-D steel frames were evaluated by Capacity Spectrum Method proposed in the ATC 40 document published in 1996. A new computer program was developed in order to define all geometric and loading data and to perform nonlinear analysis of rigid and semi rigid steel frames for which the performances will be evaluated. In case studies, 3-Floor Steel Frames that have different bay numbers were investigated in various forms according to the rigid and different semi rigid connection types. In addition, the performances these frames for various seismic regions and soil conditions were compared. According to the results, it was observed that semi rigidly connected frames are under the effect of smaller ground acceleration have greater displacement values. As a consequence of this ductile and energy dissipative response, it was seen that the stresses in the members of frame become considerably small, relative to the stresses in the rigid frames&rsquo / . Furthermore, the performances of semi-rigid frames can be affected negatively beyond such a low rigidity. Consequently, the most convenient design should be made according to the seismic and soil region where the structure to be constructed by performing the necessary studies on the connection details in order to achieve desired performance, serviceability and optimum member criteria.

La presente investigación contempla el diseño de 2 estructuras de 10 pisos, una hecha de concreto convencional y otra de un concreto ligero de arcilla expandida, cabe mencionar que para el diseño y análisis de la estructura de concreto ligero se han considerado criterios del ACI 213R para posteriormente ser verificados con las normativa peruana (norma E030 y E060); sin embargo, analizar una edificación hecha con un material que no ha sido usado con objetivo sismo resistente en nuestra nación, tiene la necesidad de ser evaluado con un método más preciso que el análisis lineal estipulado en nuestra normativa E030. Para este caso, el método de evaluación sísmico está en base al diseño por desempeño que contempla un análisis estático no lineal, el cual permite ver a mejor detalle las diferencias en el comportamiento estructural de ambas edificaciones luego de superar su estado lineal. El objetivo de evaluar ambas estructuras es el de evidenciar la influencia que tiene el uso del concreto ligero en el diseño estructural, comportamiento no lineal, desempeño sísmico y costos en comparación de una estructura de concreto convencional. Tras la evaluación por desempeño sísmico se determinó que, para este caso en específico, las edificaciones convencional y de concreto ligero no cumplen con todos los objetivos de desempeño planteados para una vivienda multifamiliar; sin embargo, la estructura de concreto ligero presenta una mejor respuesta dinámica en comparación de la estructura convencional debido a su principal propiedad, el de presentar un menor peso, que dio como resultados valores de pseudoaceleración mayores al de la estructura de concreto convencional. Finalmente se hace una comparación de costos, donde no se vio mucho ahorro al usar un concreto ligero, pero que este resultado se podría optimizar si se usara el concreto convencional y ligero de forma mixta en una edificación, teniendo en cuenta que el concreto ligero si se puede usar en elementos estructurales que resistan fuerzas sísmicas. / The present investigation contemplates the design of 2 structures of 10 floors, one made of conventional concrete and another of a lightweight concrete of expanded clay, it is worth mentioning that for the design and analysis of the structure of light concrete, criteria of the ACI 213R have been considered for subsequently be verified with Peruvian regulations (E030 and E060); However, to analyze a building made with a material that has not been used with a resistant earthquake objective in our nation, needs to be evaluated with a more precise method than the linear analysis stipulated in our E030 regulations. For this case, the seismic evaluation method is based on the performance design that contemplates a non-linear static analysis, which allows us to see in greater detail the differences in the structural behavior of both buildings after overcoming their linear state. The objective of evaluating both structures is to demonstrate the influence of the use of lightweight concrete in structural design, non-linear behavior, seismic performance and costs in comparison to a conventional concrete structure. After the evaluation for seismic performance, it was determined that, for this specific case, conventional and light concrete buildings do not meet all the performance objectives set for a multi-family home; however, the lightweight concrete structure has a better dynamic response compared to the conventional structure due to its main property, that of presenting a lower weight, which resulted in pseudo-acceleration values greater than that of the conventional concrete structure. Finally, a cost comparison is made, where there was not much savings when using a lightweight concrete, but that this result could be optimized if conventional and lightweight concrete is used mixed in a building, taking into account that the lightweight concrete does It can be used in structural elements that resist seismic forces. / Tesis

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The presented research investigated the viability of a double-braided synthetic fiber rope for providing improved performance of steel moment frames subjected to earthquake-induced ground motions. A series of experimental tests, including a 1:3-scale dynamic test and 1:6-scale shaking table tests, was conducted using Northridge ground-motion input. A series of nonlinear dynamic analytical studies, using DRAIN-2DX, was conducted to develop the experimental tests. Throughout experimental testing, the ropes exhibited a hyper-elastic loading response and a reduced-stiffness unloading response. A conditioning cycle was defined as a loading cycle induced in the rope above the highest load expected to be experienced by the rope, and was determined to be requisite for ropes intended to be used for the stated objectives of the research program. After experiencing a conditioning cycle, the rope response returned to initial conditions without permanent deformation, demonstrating repeatability of response through several loading cycles below the conditioning load. In the 1:6-scale shaking-table experiments, the ropes drastically improved the performance of the steel moment frames. Maximum and residual drift were reduced significantly, with a corresponding minimal increase to the maximum base shear. Base shear was reduced at several peaks subsequent to the initial pulse of the Northridge ground-motion input. The analytical model developed was excellent for predicting elastic response of the 1:6-scale shaking table experiments and adequate for the purpose of planning shaking table studies. Correlation of peak rope forces between the analytical model and experimental results was poor, and was attributed to limitations of the pre-defined elements used to represent the rope devices in the software program. The inability of the elements to capture the complex unloading response of the rope was specifically noted. / Ph. D.

Past earthquake events have shown that seismic damage to electrical power systems in commercial buildings, hospitals, and other systems such as public service facilities can cause serious economic losses as well as operational problems. A methodology for evaluation of the seismic vulnerability of electrical power systems is needed and all essential components of the system must be included. A key system component is the switchboard cabinet which houses many different elements which control and monitor electrical power usage and distribution within a building. Switchboard cabinets vary in size and complexity and are manufactured by a number of different suppliers; a typical cabinet design was chosen for detailed evaluation in this investigation. This study presents a comprehensive framework for the evaluation of the seismic performance of electrical switchboard cabinets. This framework begins with the introduction and description of the essential equipment in building electrical power systems and explains possible seismic damage to this equipment. The shortcomings of previous studies are highlighted and advanced finite element models are developed to aid in their vulnerability estimation. Unlike previous research in this area, this study proposes practical, computationally efficient, and versatile numerical models, which can capture the critical nonlinear behavior of switchboard cabinets subjected to seismic excitations. A major goal of the current study was the development of nonlinear numerical models that can accommodate various support boundary conditions ranging from fixed, elasto-plastic to free. Using both linear and nonlinear dynamic analyses, this study presents an enhanced evaluation of the seismic behavior of switchboard cabinets. First the dynamic characteristics of switchboard cabinets are determined and then their seismic performance is assessed through nonlinear time history analysis using an expanded suite of ground motions. The seismic responses and associated ground motions are described and analyzed using probabilistic seismic demand models (PSDMs). Based on the PSDMs, the effectiveness and practicality of common intensity measures are discussed for different components. Correlation of intensity measures and seismic responses are then estimated for each component, and their seismic performance and uncertainties are quantified in terms of engineering demand parameters. The results of this study are intended for use in the seismic vulnerability assessment of essential electrical equipment in order to achieve more reliable electrical power systems resulting in reduced overall risk of both physical and operational failures of this important class of nonstructural components.