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Research papers, The University of Auckland Library

The current seismic design practice for reinforced concrete (RC) walls has been drawn into question following the unsatisfactory performance of several RC wall buildings during the Canterbury earthquakes. An overview of current research being undertaken at the University of Auckland into the seismic behaviour of RC walls is presented. The main objectives of this research project are to understand the observed performance of RC walls in Christchurch, quantify the seismic loads on RC walls, and developed improved design procedures for RC walls that will assist in revisions to the New Zealand Concrete Structures Standard. A database summarising the performance of RC wall buildings in the Christchurch CBD was collated to identify damage modes and case-study buildings. A detailed investigation is underway to verify the seismic performance of lightly reinforced concrete walls and initial numerical modeling and small-scale tests are presented in addition to details of planned experimental tests of RC walls. Numerical modelling is being used to understand the potential influence that interactions between walls and other structural elements have on the seismic response of buildings and the loads generated on RC walls. The results from finite element analysis of a severely damaged RC wall in Christchurch highlighted the effect that the floor diaphragms have on the distribution of shear stains in the wall.

Research papers, University of Canterbury Library

A one story, two bays, approximately half scaled, perimeter moment frame containing precastprestressed floor units was built and tested at the University of Canterbury to investigate the effect of precastprestressed floor units on the seismic performance of reinforced concrete moment resisting frame. This paper gives an overview of the experimental set up and summarizes the results obtained from the test. The results show that elongation in the beam plastic hinges is partially restrained by the prestressed floor, which increases the strength of the beams much more than that being specified in the codes around the world.

Research papers, University of Canterbury Library

The purpose of this thesis is to conduct a detailed examination of the forward-directivity characteristics of near-fault ground motions produced in the 2010-11 Canterbury earthquakes, including evaluating the efficacy of several existing empirical models which form the basis of frameworks for considering directivity in seismic hazard assessment. A wavelet-based pulse classification algorithm developed by Baker (2007) is firstly used to identify and characterise ground motions which demonstrate evidence of forward-directivity effects from significant events in the Canterbury earthquake sequence. The algorithm fails to classify a large number of ground motions which clearly exhibit an early-arriving directivity pulse due to: (i) incorrect pulse extraction resulting from the presence of pulse-like features caused by other physical phenomena; and (ii) inadequacy of the pulse indicator score used to carry out binary pulse-like/non-pulse-like classification. An alternative ‘manual’ approach is proposed to ensure 'correct' pulse extraction and the classification process is also guided by examination of the horizontal velocity trajectory plots and source-to-site geometry. Based on the above analysis, 59 pulse-like ground motions are identified from the Canterbury earthquakes , which in the author's opinion, are caused by forward-directivity effects. The pulses are also characterised in terms of their period and amplitude. A revised version of the B07 algorithm developed by Shahi (2013) is also subsequently utilised but without observing any notable improvement in the pulse classification results. A series of three chapters are dedicated to assess the predictive capabilities of empirical models to predict the: (i) probability of pulse occurrence; (ii) response spectrum amplification caused by the directivity pulse; (iii) period and amplitude (peak ground velocity, PGV) of the directivity pulse using observations from four significant events in the Canterbury earthquakes. Based on the results of logistic regression analysis, it is found that the pulse probability model of Shahi (2013) provides the most improved predictions in comparison to its predecessors. Pulse probability contour maps are developed to scrutinise observations of pulses/non-pulses with predicted probabilities. A direct comparison of the observed and predicted directivity amplification of acceleration response spectra reveals the inadequacy of broadband directivity models, which form the basis of the near-fault factor in the New Zealand loadings standard, NZS1170.5:2004. In contrast, a recently developed narrowband model by Shahi & Baker (2011) provides significantly improved predictions by amplifying the response spectra within a small range of periods. The significant positive bias demonstrated by the residuals associated with all models at longer vibration periods (in the Mw7.1 Darfield and Mw6.2 Christchurch earthquakes) is likely due to the influence of basin-induced surface waves and non-linear soil response. Empirical models for the pulse period notably under-predict observations from the Darfield and Christchurch earthquakes, inferred as being a result of both the effect of nonlinear site response and influence of the Canterbury basin. In contrast, observed pulse periods from the smaller magnitude June (Mw6.0) and December (Mw5.9) 2011 earthquakes are in good agreement with predictions. Models for the pulse amplitude generally provide accurate estimates of the observations at source-to-site distances between 1 km and 10 km. At longer distances, observed PGVs are significantly under-predicted due to their slower apparent attenuation. Mixed-effects regression is employed to develop revised models for both parameters using the latest NGA-West2 pulse-like ground motion database. A pulse period relationship which accounts for the effect of faulting mechanism using rake angle as a continuous predictor variable is developed. The use of a larger database in model development, however does not result in improved predictions of pulse period for the Darfield and Christchurch earthquakes. In contrast, the revised model for PGV provides a more appropriate attenuation of the pulse amplitude with distance, and does not exhibit the bias associated with previous models. Finally, the effects of near-fault directivity are explicitly included in NZ-specific probabilistic seismic hazard analysis (PSHA) using the narrowband directivity model of Shahi & Baker (2011). Seismic hazard analyses are conducted with and without considering directivity for typical sites in Christchurch and Otira. The inadequacy of the near-fault factor in the NZS1170.5: 2004 is apparent based on a comparison with the directivity amplification obtained from PSHA.

Research Papers, Lincoln University

Increasingly, economic, political and human crises, along with natural disasters, constitute a recurrent reality around the world. The effect of large-scale disaster and economic disruption are being felt far and wide and impacting libraries in diverse ways. Libraries are casualties of natural disasters, from earthquakes to hurricanes, as well as civil unrest and wars. Sudden cuts in library budgets have resulted in severe staff reductions, privatization and even closures. The presenters share their experiences about how they have prepared for or coped with profound change.

Research papers, University of Canterbury Library

INTRODUCTION: After the 2011 Canterbury earthquake, the provision of school social work was extended into a larger number of schools in the greater Christchurch region to support discussions of their practice priorities and responses in post-earthquake schools. FINDINGS: Two main interpretations of need are reflected in the school social workers’ accounts of their work with children and families. Firstly, hardship-focused need, which represented children as adversely influenced by their home circumstances; the interventions were primarily with parents. These families were mainly from schools in low socioeconomic areas. Secondly, anxiety-based need, a newer practice response, which emphasised children who were considered particularly susceptible to the impacts of the disaster event. This article considers how these practitioners conceptualised and responded to the needs of the children and their families in this context. METHOD: A qualitative study examining recovery policy and school social work practice following the earthquakes including 12 semi-structured interviews with school social workers. This article provides a Foucauldian analysis of the social worker participants’ perspectives on emotional and psychological issues for children, particularly those from middle-class families; the main interventions were direct therapeutic work with children themselves. Embedded within these practice accounts are moments in which the social workers contested the predominant, individualising conceptualisations of need to enable more open-ended, negotiable, interconnected relationships in post-earthquake schools. IMPLICATIONS: In the aftermath of disasters, school social workers can reflect on their preferred practice responses and institutional influences in schools to offer children and families opportunities to reject the prevalent norms of risk and vulnerability.

Images, Alexander Turnbull Library

A man chats over the fence with a newcomer to the area who is digging a vegetable patch. The newcomer is wearing a red and black striped jersey, his dog wears a red and black dog-coat and there are red and black curtains in the windows of the house. The passer-by wonders where the newcomer has located to the Waikato from. The colours make it obvious that he is from Christchurch. Context - People moving away from Christchurch following the earthquake of 22 February 2011. Quantity: 1 digital cartoon(s).

Research Papers, Lincoln University

The 48hr Design Challenge, run by the Christchurch City Council and held at Lincoln University, provided an opportunity for Council to gain inspiration from the design and architecture industry, while testing the draft Central City Plan currently being developed. The Challenge was a response to the recent earthquakes in Christchurch and brought together local and international talent. A total of 15 teams took part in the Challenge, with seven people in each including engineers, planners, urban designers, architects and landscape architects, as well as one student on each team. The four sites within the Red Zone included the Cathedral Square and BNZ Building; 160 Gloucester Street; the Orion NZ Building at 203 Gloucester Street; and 90 Armagh Street, including the Avon River and Victoria Square. The fifth site, which sits outside the Red Zone, is the former Christchurch Women’s Hospital at 885 Colombo Street. This is team SoLA's entry for 160 Gloucester Street.

Images, Alexander Turnbull Library

The title is 'Gambling on the rise in Christchurch'. Several vignettes show two men running in the 'Porta-loo stakes (runs)'; people betting on the 'size of the next shake'; people betting on 'who will have the last chimney standing'; a man sitting over a pot on a little gas ring wondering 'How long will it take to boil a 3 minute egg... when it's minus 10 in the kitchen'; someone in a car wondering 'Whose street can wipe out the most engine sumps'; and someone wondering 'Which power company will be first to put people before profits'. Context: The way of things following the earthquakes of September 4 2010, 22 February 2011 and 13 June 2011. The Problem Gambling Foundation says it is concerned more Christchurch people are turning to gambling to combat stress from earthquakes. It says spending on pokie machines in Christchurch has risen by almost $4 million, going against a downward national trend. The foundation says the data released by the Department of Internal Affairs shows spending on gaming machines rose by more than $3,800,000 in Christchurch city to almost $23 million. (Radio NZ News 26 July 2011) Colour and black and white versions available Quantity: 2 digital cartoon(s).

Images, UC QuakeStudies

A photograph of the earthquake damage to the former Canterbury Public Library on the corner of Hereford Street and Cambridge Terrace. The bricks in the corner of the building have crumbled and masonry can be seen on the footpath below. Wire fences have been placed around the building as a cordon.

Research papers, University of Canterbury Library

The term resilience‘’is increasingly being used in a multitude of contexts. Seemingly the latest buzz‘’word, it can mean many things to many people, in many different situations. In a natural hazard context, the terms sustainable planning‘’, and resilience‘planning are now’being used, often interchangeably. This poster provides an overview of resilience and sustainability within a land use planning and natural hazard context, and discusses how they are interrelated in the situation of the earthquake impacted city of Christchurch, New Zealand.

Images, Alexander Turnbull Library

A man representing 'Chch' (Christchurch) walks a tightrope between two cliffs. Suddenly below there are piles of dollar notes from the 'AMI' and he says 'A safety net at last!' Context - Christchurch earthquake problems with insurance. Insurers are saying that they will only pay for repairs for houses in the Red zone that are destined for demolition but that are relatively undamaged. Maybe the cartoon is expressing an ironic response to AMI's 'total replacement' policy. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The cartoon is headed 'Whitebait - How to spot the difference.' Below are two frames; the one on the left shows a brown fish wearing goggles and breathing apparatus, it is from the East Coast and is described as 'drab brown' and 'tastes like dung'; the one on the right is pink and wears a sun hat and sunglasses, it is from the West Coast and is described as 'lightly tanned' and 'tastes like coconut'. Context: The whitebait from the east coast has been contaminated by the Canterbury earthquakes. Quantity: 1 digital cartoon(s).