This thesis presents the development and the seismic performance evaluation of steel MRFs with nonlinear replaceable links. Although existing MRFs can provide life safety during a design level earthquake, they are expected to sustain significant damage at the locations of flexural yielding fuses in the beams. The design of the fuse is also interlinked with the design of the beam, often resulting in over-design. These drawbacks can be mitigated by introducing replaceable links at the locations of expected inelastic action. Four full-scale beam-to-column subassemblages with two link types were tested under cyclic loading: i) double channels with bolted web connections, ii) W-sections with bolted end plate connections. The experiments demonstrated that MRFs with replaceable links can provide strength and ductility equivalent to existing MRFs. Finite element models were then developed to capture the observed experimental responses, including local buckling, bolt slipping, and bolt bearing. Finally, preliminary design guidelines were proposed.

The choice of reference frames used in simulations is typically fixed in dynamic models based on modeling decisions made early during their development, restricting model fidelity, numerical accuracy and integration into large-scale simulations. Individual simulation components typically need to model the transformations between multiple reference frames in order to interact with other components, resulting in additional development effort, time and cost. This dissertation describes the methods for defining and managing different reference frames in a simulation, thereby creating a shared simulation environment that can provide reference frame transformations, comprising of kinematics and rotations, to all simulation components through a Reference Frame Manager. Simulation components can use this Reference Frame Manager to handle all kinematics and rotations when interacting with components using different reference frames, improving the interoperability of simulation components, especially in parallel and distributed simulation, while reducing their development time, effort and cost. The Reference Frame Manager also facilitates the development of Generic Dynamic Models that encapsulate the core service of dynamic model, enabling the rapid development of dynamic models that can be reused and reconfigured for different simulation scenarios and requirements. The Reference Frame Manager can also be used to introduce Intermediate Frames that bound the magnitudes of vehicle states, reducing roundoff error and improving numerical accuracy.

The infrequent nature of earthquakes in the Central and Eastern United States (CEUS), and the fact that none with intensity comparable to the New Madrid sequence of 1811 12 or the Charleston earthquake of 1886 has occurred in the past century, have caused the earthquake hazard in the region to be ignored until quite recently. The seismic performance of reinforced concrete (RC) frames in the CEUS, which have primarily been designed for gravity load effects, is expected to be deficient when subjected to earthquakes that are judged, in recent seismological research, as being plausible in the New Madrid Seismic Zone (NMSZ). The objective of this study is to develop a set of probability-based tools for efficient uncertainty analysis and seismic vulnerability and risk assessment of such gravity load designed (GLD) RC frames and to use these tools in evaluating the seismic vulnerability of RC frames that are representative of the building inventory in Memphis, TN the largest population center close to the NMSZ. Synthetic earthquake ground motions for the CEUS that are available from two different Mid-America Earthquake (MAE) Center projects were used in the finite element-based simulations for determining the seismic demand on the GLD RC frames by nonlinear time history analysis (NTHA). A beam-column joint model was developed to address the deficiencies in the joints of GLD frames and was incorporated in the finite element structural models. Seismic fragilities were derived for low-, mid-, and high-rise GLD RC frames. Various sources of uncertainty were propagated through the analysis, and their significance for fragility assessment was examined. These fragilities were used to evaluate the vulnerability of the RC frame inventory in Memphis, TN with regard to performance-based design objectives, defined in terms of performance levels associated with reference earthquake hazard levels. This performance appraisal indicated that GLD RC frames do not meet the life safety and collapse prevention performance objectives that are found in recent building codes and guidelines for performance-based earthquake engineering.

The No Child Left Behind Act of 2001, fundamentally changed the focus of education in the United States from that of providing an opportunity for all to learn to mandating that all do learn. Central to this Act are the measures of school accountability established through assessment of learning policies. The development of these policies initiate with federal, state, and local governance bodies, but implementation takes place by individual teachers. Therefore, the failure of individual teachers to implement assessment policies with fidelity creates a fissure at the core of institutional credibility. The purpose of this study is to investigate the relationship between teachers’ values and ethical frames and behavior with respect to academic misconduct. Findings offer clues as to how academic dishonesty might be reduced. There exists a large body of research that has probed academic dishonesty, values and ethical frames; however, there appears to be a void in research that distinctly connects the three. Utilizing a survey instrument, data were collected from elementary teachers (N=155) in one suburban school district. The collected data were then analyzed using both descriptive and inferential statistical tests to inform six research questions. In some incidents, the small sample size produced violations of the assumptions of nonparametric statistical tests, thus hindering deeper analysis of selected data. However, the results in general appeared to support the hypothesis that elementary teachers appeared to engage in academic misconduct. The findings also appeared to suggest misconduct was influenced by social adaptation theory (R2N = .32); organizational socialization (Wald (1) =5.79, p < .05), values (Wald (1) =5.16, p < .05), and ethical frames (Wald (4) =25.22, p < .001). Thus, this study concluded that factors such as collaboration and professional development can possibly be utilized to reduce policy violations.

A two-phase research program was undertaken numerically to assess the behavior of the beam outside of the link that is designed for overstrength of the link in eccentrically braced frames (EBFs). In the first phase, software was developed to conduct a statistical analysis of the typical cases designed according to the AISC Seismic Provisions for Structural Steel Buildings. In this analysis, it was noticed that most of the statistically analyzed cases do not satisfy the code requirement provided for overstrength factor. Furthermore, the analyses results revealed that troublesome designs are highly influenced by normalized link length and slenderness of the beam. In this phase, redistribution of forces between beam and brace after the yielding of beam was also studied and it was observed that the forces not carried by the yielded beam are taken by the brace. In second phase, a total of 91 problematic designs were analyzed on finite element program to investigate the effective parameters on the overstrength issue, and overall and local stability of the beam outside of the links. According to analysis results, it was observed that unbraced beam length and flange slenderness are responsible for the stability of the system. Based on these results, the boundary values were suggested to prevent lateral torsional buckling of the beam and local buckling of the brace connection panel separately. Moreover, the overstrength factor specified by code was found conservative for the intermediate and long links although it is fit for the short links.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 96-103).

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This dissertation is a study of how various German narratives from the nineteenth century to the present tell stories that are interrupted or framed by discourse on storytelling itself. More specifically, I examine the various means by which authors in different periods have sought to address and undermine the idea that a story must be believable. The classic frame narrative is one example of how the problem of credibility has been confronted, and yet I suggest that frames are often employed by authors for the very reason that contrary to their perceived function, they are inherently unstable. Frame narratives, interwoven stories, unbelievable occurrences, or less than credible storytellers are all ways by which the texts examined here reflect on their own production and create ambiguity about levels of reality and the connections between different story levels.

A new method of connecting cross-frames to bridge girders had been proposed to alleviate concerns with current design practices. This new, half-pipe detail needs to be examined for fatigue issues that may exist which would make it infeasible as a replacement candidate for the current bent-plate design. A program of laboratory testing was carried out to determine the comparative performance between the half-pipe and the bent-plate designs. These tests were then translated into a finite element model which was examined to determine behavior over a wide range of designs scenarios. Finite element results, along with the laboratory testing data, were used to determine the appropriate use of the half-pipe stiffener. / text

published_or_final_version / Civil Engineering / Master / Master of Philosophy