There is a large building stock in seismic regions of Turkey that require seismic upgrades. In order to minimize the disturbance to occupants and not to intervene with the functioning of the building, external strengthening methods can be preferred among different alternatives. This study reports the experimental findings on the upgrading of deficient reinforced concrete frames with external installed structural components. Specimens strengthened with an externally reinforced concrete shear wall, external steel frames, steel plate shear wall and one as-built reference 1/3-scale portal frame specimens were tested under constant gravity load and increasing cyclic displacement excursions. The RC frames had deficiencies those mimic the existing deficient building stock in Turkey. The test results showed that the external upgrading can increase both the lateral stiffness and strength of deficient RC frames considerably. Finite element analyses were conducted to specimen models to investigate the behaviors numerically. Furthermore, corresponding single degree of freedom (SDOF) models of specimens were generated to perform dynamic analysis. Results show the importance of hysteretic response and enhancement of energy dissipation capability with drift control.

Most of the current optimization techniques for the design of light-weight structures are unable to generate structural alternatives at the concept stage of design. This research tackles the challenge of developing an optimization method for the early stage of design. The main goal is to propose a procedure to optimize material and shape of stiff shafts in torsion. / Recently introduced for bending stiffness design, shape transformers are presented in this thesis for optimizing the design of shafts in torsion. Shape transformers are geometric parameters defined to classify shapes and to model structural efficiency. The study of shape transformers are centered on concept selection in structural design. These factors are used to formulate indices of material and shape selection for minimum mass design. An advantage of the method of shape transformers is that the contribution of the shape can be decoupled from the contribution of the size of a cross-section. This feature gives the designer insight into the effects that scaling, shape, as well as material have on the overall structural performance. / Similar to the index for bending, the performance index for torsion stiffness design is a function of the relative scaling of two cross-sections. The thesis examines analytically and graphically the impact of scaling on the torsional efficiency of alternative cross-sections. The resulting maps assist the selection of the best material and shape for cross-sections subjected to dimensional constraints. It is shown that shape transformers for torsion, unlike those for bending, are generally function of the scaling direction. / The efficiency maps ease the visual contrast among the efficiency of open-walled cross-sections and that of close-walled cross-sections. As expected, the maps show the relative inefficiency of the former compared to the latter. They can also set the validity range of thin- and thick-walled theory in torsion stiffness design. The analytical results are validated with the numerical data obtained from ANSYS to guarantee the consistency of the models. The thesis concludes with three case studies that demonstrate the method.

Thesis (M.E.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 180-184). Also available via the World Wide Web.

Thesis (M.E.)--University of Canterbury, 2005. / Typescript (photocopy). Includes bibliographical references (leaves 222-228). Also available via the World Wide Web.

In October 2020 Peter Wolodarski, the editor-in-chief of the Swedish newspaper Dagens Nyheter (DN), announced that he wanted to improve the news coverage of the climate crisis. The aim of this study is to investigate whether DN has changed their way of reporting on the climate crisis through text and pictures within six months, and if so what those changes are. Framing theory is central in this study as it identifies the usage of generic and theme specific frames in DN’s articles. This is done by comparing all articles in September 2020 and March 2021 that contain the topic “climate crisis” published on their online service. The usage of pictures was also studied for additional context. In order to study this the methods qualitative text analysis and semiotic image analysis were used. To provide results the data then underwent a quantitative analysis as well as qualitative analysis.The findings of the study show that DN has shifted their usage of generic frames, meaning a change in which scale the climate crisis is portrayed, and an increased and widened usage of specific frames in their articles. However, the usage of pictures has not changed notably. In conclusion, does DN in fact seem to have changed their overall reporting on the climate crisis within the studied period. The study contribution is an added understanding of papers reporting on the clime crisis online as well as media’s usage of frames and how those can change in a relatively short period of time.

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The buildings that are designed according to the building codes generally perform well at severe performance objectives (like life safety) under high earthquake hazard levels. However, the building performance at low performance objectives (like immediate occupancy) under low earthquake hazards is uncertain. The motivation of this research is to modify the design and detailing rules to make the traditional systems perform better at multi-level hazards. This research introduces two new structural steel systems: hybrid Buckling Restrained Braced Frames (BRBF) and hybrid steel Moment Frames (MF). The "hybrid" term for the BRBF system comes from the use of different steel material including carbon steel (A36), high-performance steel (HPS) and low yield point (LYP) steel. The hybridity of the moment frames is related to the sequence in the plastification of the system which is provided by using weaker and stronger girder sections. Alternative moment frame connections incorporating the use of LYP steel plates are also investigated. The hybrid BRBF approach was evaluated on seventeen regular (standard) frames with different story heights, seismic design categories and building plans. By varying the steel areas and materials in the BRB cores, three hybrid BRBFs were developed for each regular (standard) frame and their behavior was compared against each other through pushover and incremental dynamic analyses. The benefits of the hybridity were presented using different damage measures such as story accelerations, interstory drifts, and residual displacements. Collapse performance evaluation was also provided. The performance of hybrid moment frames was investigated on a design space including forty-two moment frame archetypes. Two different hybrid combinations were implemented in the designs with different column sections and different strong column-weak beam (SC/WB) ratios. The efficiency of the hybrid moment frame in which only the girder sizes were changed to control the plastification was compared with regular moment frame designs with higher SC/WB ratios. As side studies, the effect of shallow and deep column sections and SC/WB ratios on the moment frame behavior were also investigated.   In order to provide adequate ductility in the reduced capacity bays with special detailing, alternative hybrid moment frame connections adapting the use of low strength steel were also studied. / PhD

It has been more than ten years since the 9/11 attacks in 2001, but the events related to the attacks are still a focus for the whole world. This study examined the news coverage of the 9/11 tenth anniversary from Phoenix TV and CNN, which are among the most influential news media in China and the U.S., respectively. A systematic content analysis was performed using latest news, opinion articles, photographs, and videos as classified by CNN and Phoenix TV on their commemorative 9/11 tenth anniversary websites. Framing theory guided this thesis project. The results offer some evidence regarding differences in the selection and use of frames in the U.S. and Chinese media. Results also suggest that global media share news resources for global events. / Master of Arts