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Research papers, The University of Auckland Library

The city of Christchurch has experienced over 10,000 aftershocks since the 4th of September 2010 earthquake of which approximately 50 have been greater than magnitude 5. The damage caused to URM buildings in Christchurch over this sequence of earthquakes has been well documented. Due to the similarity in age and construction of URM buildings in Adelaide, South Australia and Christchurch (they are sister cities, of similar age and heritage), an investigation was conducted to learn lessons for Adelaide based on the Christchurch experience. To this end, the number of URM buildings in the central business districts of both cities, the extent of seismic strengthening that exists in both cities, and the relative earthquake hazards for both cities were considered. This paper will report on these findings and recommend strategies that the city of Adelaide could consider to significantly reduce the seismic risk posed by URM buildings in future earthquake

Research papers, The University of Auckland Library

Eccentrically Braced Frames (EBFs) are a widely used seismic resisting structural steel system. Since their inception in the late 1970s, they have been a viable option with an available stiffness that is between simple braced systems and moment resisting systems. A similar concept, the linked column frame (LCF), uses shear links between two closely spaced columns. In both cases, the key component is the active link or the shear link, and this component is the objective of this study. The performance of high rise EBF buildings in the 2010 and 2011 Christchurch earthquakes was beyond that which was expected, especially considering the very high accelerations recorded. As the concrete high-rises were torn down, two EBF buildings remained standing and only required some structural repair. These events prompted a renewed interest in bolted shear links, as well as their performance. While some research into replaceable shear links had already been done (Mansour, 2011), the objectives of this study were to improve on the shear link itself, with the consideration that links built in the future are likely to be bolted. The main components of this study were to: 1. Reduce or eliminate the requirements for intermediate web stiffeners, as they were suspected of being detrimental to performance. Furthermore, any reduction in stiffening requirements is a direct fabrication cost saving. Links with low web aspect ratios were found to achieve exceptional ductilities when no stiffeners were included, prompting new design equations. 2. Ensure that the stresses in the ends of links are adequately transferred into the endplates without causing fractures. Although most of the experimental links had web doubler plates included, four had varied lengths of such doubler plates from 0.0 in. to 8.0 in. The link without any doubler plates performed to a similar level to its peers, and thus it is likely that links with quality end details may not need web doubler plates at all. 3. Evaluate the performance of a link with double sided stiffeners without the use of web welds, as opposed to conventional single sided, welded stiffeners. This link performed well, and web-weld-less double sided stiffeners may be an economical alternative to conventional stiffeners for deeper sections of links. 4. Evaluate the performance of a link with thin endplates that are made efficient with the use of gusset plates. This link performed to an acceptable level and provides evidence for a cost effective alternative to thick endplates, especially considering the high overstrength end moments in links, typically requiring 16-bolt connections. 5. Examine the potential use of an alternative EBF arrangement where the collector beam is over sized, and the link section is formed by cutting out parts of the beam's web. After running a series of finite element models each with a unique variation, a number of approximate design rules were derived such that future research could develop this idea further experimentally. 6. Ensure that during testing, the secondary elements (members that are not the shear link), do not yield and are not close to yielding. None of the instrumented elements experienced any unexpected yielding, however the concerns for high stresses in the collector beam panel zone during design were warranted. The use of an existing New Zealand design equation is recommended as an extra check for design codes worldwide. The above objectives were mainly conducted experimentally, except: the data set for item 1 was greatly expanded through the use of a calibrated numerical model which was then used in an extensive parametric study; item 5 was purely finite element based; and, a small parametric study was included for item 3 in an attempt to expand on the trends found there

Research papers, The University of Auckland Library

What does it mean to “be in a mood” at school? This question guides this thesis, which analyses the relationship between young people’s experiences of moods and the discourses and pedagogies of moods they encounter at school. The emotions and moods of young people in Christchurch, New Zealand, have, in recent years, come under considerable scrutiny. A national decline in rates of youth mental health and concern over the lasting psychological effects of the 2010-2011 Christchurch Earthquakes have justified increased attention to and funding for youth mental health promotion and school-based mental health education programs. Drawing on a year-long school ethnography at a public girl’s high school in Christchurch with 22 Year 10 students (age 14-15), this thesis examines how young people interact with state and psychiatric discourses of youth and mental health. It explores how young people integrate and transform these discourses in their experiences and knowledges of moods as they relate to mental health, education, friendships, and the (in)stability of the self in time. Additionally, this thesis proposes an anthropological reconsideration of moods. Developing insights from phenomenological and medical anthropology and bringing them into conversation with ethnographic analysis, the approach to moods in this thesis sees two necessarily interconnected ways in which moods become significant for understanding subjectivity and contemporary society. On the one hand, moods are an integral dimension of phenomenological experience in which it is possible to dwell in affective ambiguities, producing open-ended horizons of experience. On the other hand, young people’s experience of moods is refracted through moods’ medicalised formulation as experience that can be bounded, taxonomized, transformed into kinds of knowledge about the self, and thus acted on in distinct and morally situated ways. Attending to the experience of “being in a mood” at school reveals how medical and psychiatric knowledges are woven into moral experience in the everyday. This moral experience of moods has critical implications for how young people in New Zealand today situate the self in relationships, in the world, and in time, and therefore is particularly revealing for developing anthropological understandings of teenage subjectivity