Severe earthquakes cause damage to buildings. One measure of damage is the residual drift. Large residual drifts suggest expensive repairs and could lead to complete loss of the building. As such, research has been conducted on how to reduce the residual drift. Recent research has focused on self-centering frames and dual systems, both of which increase the post-yield stiffness of the building during and after an earthquake. Self-centering systems have yet to be adopted into standard practice but dual systems are used regularly. Dual systems in steel buildings typically combine two types of traditional lateral force resisting systems such as bucking restrained braced frames (BRBFs) and moment resisting frames (MRFs). However, the cost of making the moment connections for the MRFs can make dual systems costly. An alternative to MRFs is to use gravity columns as the secondary system in a dual system. The gravity columns can be used to help resist the lateral loads and limit the residual drifts if the lateral stiffness of the gravity columns can be activated. By restraining the displacement of the gravity columns, the stiffness of the columns adds to the stiffness of the brace frame, thus engaging the lateral stiffness of the gravity columns. Three methods of engaging the stiffness of the gravity columns are investigated in this thesis; one, fixed ground connections, two, a heavy elastic brace in the top story, and three, a heavy elastic brace in the middle bay. Single and multiple degree of freedom models were analyzed to determine if gravity columns can be effective in reducing residual drift. In the single degree of freedom system (SDOF) models, the brace size was varied to get a range of periods. The column size was varied based on a predetermined range of post-yield stiffness to determine if the residual drift decreased with higher post-yield stiffness. Three and five story models were analyzed with a variety of brace and column sizes and with three different configurations to activate the gravity columns. Using gravity columns as part of a dual system decreases the residual drift in buildings. The results from the SDOF system show that the residual drift decreased with increased post-yield stiffness. The three and five story models showed similar results with less residual drift when larger columns were used. Further, the models with a heavy gravity column in the top story had the best results.

This thesis illuminates the experiences, motives, and framing process of a cohort of homebirthing women in Tucson, Arizona who embody the collective action frames of the national homebirth movement. A model of birth frame construction, alignment and adoption is presented that expands current theory on social movement framing processes, cognitive liberation, and life politics in health and self-help related movements. The study explores the evolution of homebirth midwifery nationally and locally. It articulates the main collective action frames that argue against standard maternity care and presents the alternatives proffered by the homebirth movement. It presents micro-level experiences of movement pioneers, macro-articulations of movement leaders, respondent's micro-level birth model framing processes; and how "life politics" have changed birth culture in America. Written materials augmented data obtained from in-depth interviews with (n=38) respondents who homebirthed in Tucson between 1970 and 2000. Content analysis was utilized and grounded theory was employed.

This paper provides an assessment of the seismic performance of a code-designed buckling restrained braced frame building using the performance-based analysis procedures prescribed in ASCE 41-06. The building was designed based on the standards of the ASCE 7-05 for a typical office building located in San Francisco, CA. Nonlinear modeling parameters and acceptance criteria for buckling restrained brace components were developed to match ASCE 41-06 design standards for structural steel components, since buckling restrained braces are not currently included in ASCE 41-06. The building was evaluated using linear static, linear dynamic, nonlinear static and nonlinear dynamic analysis procedures. This study showed that the linear procedures produced more conservative results, with the building performing within the intended Life Safety limit, while the nonlinear procedures predicted that the building performed closer to the Immediate Occupancy limit for the 2/3 maximum considered earthquake hazard. These results apply to the full maximum considered earthquake hazard as well, under which the building performed within the Collapse Prevention limit in the linear analysis results and within the Life Safety limit in the nonlinear analysis results. The results of this paper will provide data for the engineering profession on the behavior of buckling restrained braced frames as well as performance based engineering as it continues to evolve.

In mid- to high-rise structures, dual systems (DS) enable a structural designer to satisfy the stringent drift limitations of current codes without compromising ductility. Currently, ASCE 7-05 permits a variety of structural systems to be used in combination as a dual system yet the design requirements are limited to the following statement: Moment frames must be capable of resisting 25% of the seismic forces while the moment frames and braced frames or shear walls must be capable of resisting the entire seismic forces in proportion to their relative rigidities. This thesis assesses the significance of the 25% design requirement for the secondary moment frames (SMF) in dual systems with consideration of current structural engineering practice. Three 20-story buckling-restrained braced frame (BRBF) dual system structures were designed with varying relative strengths between the braced and special moment frame systems. The SMF system wa designed for 15%, 25%, and 40% of seismic demands and the BRBF system design has been adjusted accordingly based on its relative stiffness with respect to the moment frame. These structures were examined with nonlinear static and nonlinear dynamic procedures with guidance from ASCE 41-06. The drift, displacement and ductility demands, and the base shear distribution results of this study show similar responses of the three prototype structures. These results indicate a secondary moment frame designed to less than 25% of seismic demands may be adequate for consideration as a dual system regardless of the 25% rule.

The first purpose of this research is to investigate the effect of added viscous fluid dampers on a nine story special steel moment frame designed for strength in Seattle. At the initial stages of the work, knowing the fact that moment frames are almost always controlled by drift, it was thought that two different moment frames, controlled by strength or controlled by drift (stiffness), could be designed in Seattle and the effect of additional dampers on the structural behavior of the strength controlled design could be studied. However, since ASCE 7 permits determining the elastic drifts by using the seismic design forces based on the computed fundamental period of the structure, without the upper limit (CuTa), the strength controlled design satisfied the drift limit requirements of ASCE 7. Although the strength controlled design meets the drift requirements, the stability checks of both ASCE 7 and the AISC Seismic Design Manual were not satisfied. Thus, the strength controlled frame was redesigned to meet the stability requirements, and the process is called stability controlled design. By adding supplemental dampers to the strength controlled design, it was expected that the seismic drift would be controlled and a better structural behavior would be obtained in terms of dynamic stability. Incremental Dynamic Analysis (IDA) was implemented to investigate the benefits of the dampers on the structural behavior. Using ten different earthquakes scaled up to a maximum target multiplier two, with ten increments, damage measures such as interstory drift, residual displacement, IDA dispersion, base shear, and roof displacement were studied. Using IDA dispersion, the effect of dampers on dynamic instability was also investigated in this study. As a result, it was found that as the damping of the structure increases with the help of added dampers, the structural response gets better. Maximum and residual roof displacements, interstory drifts, and IDA dispersion decreases with increasing damping. In addition, by using supplemental damping, most of the collapses that occur for the inherently damped frames are prevented. The second purpose of this research is to develop an improved "Hybrid" moment frame without added damping but by controlling the inelastic behavior. Hybrid Frames were designed as the combination of three different moment frames: Special, Intermediate and Ordinary Moment Frames (SMF, IMF, OMF). The design procedure of each bay, which corresponds to different moment frame systems, follows the rules of the related moment frame for that bay. By varying the plastic hinge capacities across the same level stories, four different Hybrid Frame designs were obtained. Nonlinear static pushover analysis was applied to these frames, and as expected, the more reduction in the plastic capacity of the Hybrid Frame, the earlier the pushover curve starts yielding and the later the negative post yield stiffness of the pushover curve was reached. It was observed that the effect of early plastic hinge forming in the frame, which caused inelastic hysteretic damping, and the relatively late formation of negative post yield stiffness resulted in a better dynamic behavior. As a result of the IDA studies, as the frames become more "hybrid", the residual displacements decrease significantly and then collapses are even prevented. This is considered as the positive effect of reaching the negative post yield stiffness late. The residual displacement was reduced for low intensity gentle earthquakes. The ductility demand IDA study proves that as the frames become more hybrid, the ductility demand increases for the special detailing frame, where plastic capacity was reduced, and decreases for the ordinary detailing frame, where the plastic capacity was increased. The Hybrid Frame system is expected to perform better than the traditional special moment frame, and to be more economical than the special moment frame because of the limited amount of special detailing. / Master of Science

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<p> This study deals with a method of analysis and the associated computer program that can capture the full nonlinear response of twodimensional reinforced concrete and steel plane frames subjected to dynamic loads, including blast and impact. Most of the relevant parameters that are normally neglected by similar available analysis tools have been considered in the present study. These include tension stiffening and concrete cracking, confinement effect and strain rate effect. Interaction between axial and bending deformations has also been accounted for. Four different constitutive models for concrete have been used and compared to each other together with multiple formulae accounting for the strain rate effect. The proposed analysis procedure was verified against other sophisticated software and experimental results and has proven to be a reliable means of analysis. </p> <p> The strain rate effect is shown to be a key parameter that plays an important role in the overall behaviour of structures under blast loads. Neglecting this effect does not necessarily lead to a more conservative design because it increases the overall stiffness of the structure which causes it to attract higher forces. This increase is proportional to the strain rate, which makes it particularly important in the case of blast loading where the strain rate can reach up to 1000 sec⁻¹. </p> / Thesis / Master of Applied Science (MASc)

Increasing calls for regional independence are being made in several European countries, and such calls are accompanied by growing public support for secessionism. Over the last decade, Catalonia and Scotland have enjoyed the highest level of political mobilization for secession in the European Union. This research highlights the role of the media in changing attitudes toward independence and studies regionalist parties' strategic choices to understand their electoral success at the regional elections at a time of fast growth of independence sentiments among the population. This study employs different methods: process tracing to focus on the specificities of the independence process in a view to understand how the secessionist agenda transformed the cases; frame analysis of media links the theoretical arguments and their representation in the public discourse; content analysis of regional parties’ electoral programs via Regional Manifesto Project approach helps to define the strategic choices of regionalist parties which brought success to their secessionist agenda at the regional elections; most-similar cases comparative analysis allows to identify commonality and differences between the cases of Catalonia and Scotland. This dissertation uncovers how: the media communicate regionalist arguments to the audience; the media justify independence claims; regionalist parties strategize their secessionist programs. First, a strong pro-region bias is the main feature of media coverage. Secondly, saliency in influenced by the political process as a largely exogeneous factor, but the framing process may also influence reality by giving particular meaning to the major political events and by framing them as political opportunities or as having transformative power. Third, the political competition structure contributes to the strategic choices of political parties. My research contributes to the framing literature by considering the role of diagnosis, prognostic, and motivational framing in the independence discourse. It highlights the extent of pro-region message flows vis-à-vis pro-center and neutral messages in media communication. My analysis contributes to previous research on regionalist parties by making an in-depth case study to differentiate between subsuming and blurring strategies adopted by secessionist actors.

This study compares repertoire and framing between two protests in the early Dutch environmental movement and two protests in the modern Dutch environmental movement. The aim of the study is to find differences and similarities between the two time periods the protests take place in. The four cases are studied using the comparative case study method, specifically doing a historical comparison. In each case, the theoretical concepts of repertoire and framing are analyzed. Each case is studied through a qualitative analysis of archival and secondary sources, including newspaper articles, publications and social media posts. Using the theoretical concepts of framing and repertoire, several similarities and differences are found between the four cases. All four cases use the frame of the threat to human health in their campaigns and aimed for a low threshold for people to join their campaigns. Frames differed more across campaigns with different topics than across campaigns from different time periods. In repertoire, cases differed across time periods more than within time periods. The contemporary cases focus on commitment by showing the willingness to bear great personal risk, whereas the historical cases focus on showcasing their worthiness through alliances with strategic actors. Overall, the comparative historical analysis employed in this research reveals that there are greater differences between time periods when it comes to repertoire than in framing, showing that repertoire is defined more by time period than framing for the chosen cases.

Research has shown that a frame for an n-dimensional real Hilbert space offers phase retrieval if and only if it has the complement property. There is a geometric characterization of general frames, the Han-Larson-Naimark Dilation Theorem, which gives us the necessary and sufficient conditions required to dilate a frame for an n-dimensional Hilbert space to a frame for a Hilbert space of higher dimension k. However, a frame having the complement property in an n-dimensional real Hilbert space does not ensure that its dilation will offer phase retrieval. In this thesis, we will explore and provide what necessary and sufficient conditions must be satisfied to dilate a phase retrieval frame for an n-dimensional real Hilbert space to a phase retrieval frame for a k-dimensional real Hilbert.