As the result of the September 4th 2010 Canterbury earthquake and associated aftershocks on February 22nd 2011 and June 13th 2011, final examinations in the two 100 level economics papers at Canterbury University were cancelled at short notice in semester one 2011. The final examination weightings were spread over the remaining assessments to obtain a final grade for students. This paper attempts to establish how different online assessment conditions affect final grade distributions when online assessments are substituted for an invigilated final examination. Pearson correlation coefficients and Spearman rank order correlation coefficients are used to show that there is a greater correlation between online quizzes and invigilated assessments when those quizzes are only available for a restricted period of time, compared to the whole semester. We find that online quizzes are more closely correlated with invigilated assessments when the first attempt at a quiz is recorded, as opposed to the highest of two attempts. We also find that using the first attempt leads to less grade disruption when compared to a “normal” semester that includes a final examination. Finally, the actual impact on student grades when online quizzes are substituted for a final examination is discussed.
On September the 4th 2010 and February 22nd 2011 the Canterbury region of New Zealand was shaken by two massive earthquakes. This paper is set broadly within the civil defence and emergency management literature and informed by recent work on community participation and social capital in the building of resilient cities. Work in this area indicates a need to recognise both the formal institutional response to the earthquakes as well as the substantive role communities play in their own recovery. The range of factors that facilitate or hinder community involvement also needs to be better understood. This paper interrogates the assumption that recovery agencies and officials are both willing and able to engage communities who are themselves willing and able to be engaged in accordance with recovery best practice. Case studies of three community groups – CanCERN, Greening the Rubble and Gap Filler – illustrate some of the difficulties associated with becoming a community during the disaster recovery phase. Based on my own observations and experiences, combined with data from approximately 50 in-depth interviews with Christchurch residents and representatives from community groups, the Christchurch City Council, the Earthquake Commission and so on, this paper outlines some practical strategies emerging communities may use in the early disaster recovery phase that then strengthens their ability to ‘participate’ in the recovery process.
We aim to investigate the role of insurance in business recovery following the devastating Christchurch earthquake in February, 22nd, 2011. We analyze data from two business surveys conducted after the earthquake to examine how insurance affected business operation in the aftermath of the earthquake both in the short-term and longer-term. For the short-term analysis, we use a combination of propensity score matching (PSM) and linear probability model (LPM) to analyze the data. We first estimate the propensity scores for insurance take-up of each firm conditional on the firm’s individual characteristics. Stratification based on the estimated propensity scores is used to match the treated (insured) and the control (uninsured) firms. We then estimate the probability of firms’ continuing operations with a set of control variables to account for the level of damage and disruption caused by the quake in each stratum. We find little evidence of any beneficial effect of insurance coverage on business continuity in the short-run. For the longer-term analysis, we analyze the available survey data using logistic regression. The result suggests that business interruption insurance significantly promotes increased level of long-term productivity for surviving firms following the earthquake.
In the period between September 2010 and December 2011, Christchurch was shaken by a series of strong earthquakes including the MW7.1 4 September 2010, Mw 6.2 22 February 2011, MW6.2 13 June 2011 and MW6.0 23 December 2011 earthquakes. These earthquakes produced very strong ground motions throughout the city and surrounding areas that resulted in soil liquefaction and lateral spreading causing substantial damage to buildings, infrastructure and the community. The stopbank network along the Kaiapoi and Avon River suffered extensive damage with repairs projected to take several years to complete. This presented an opportunity to undertake a case-study on a regional scale of the effects of liquefaction on a stopbank system. Ultimately, this information can be used to determine simple performance-based concepts that can be applied in practice to improve the resilience of river protection works. The research presented in this thesis draws from data collected following the 4th September 2010 and 22nd February 2011 earthquakes. The stopbank damage is categorised into seven key deformation modes that were interpreted from aerial photographs, consultant reports, damage photographs and site visits. Each deformation mode provides an assessment of the observed mechanism of failure behind liquefaction-induced stopbank damage and the factors that influence a particular style of deformation. The deformation modes have been used to create a severity classification for the whole stopbank system, being ‘no or low damage’ and ‘major or severe damage’, in order to discriminate the indicators and factors that contribute to ‘major to severe damage’ from the factors that contribute to all levels of damage a number of calculated, land damage, stopbank damage and geomorphological parameters were analysed and compared at 178 locations along the Kaiapoi and Avon River stopbank systems. A critical liquefiable layer was present at every location with relatively consistent geotechnical parameters (cone resistance (qc), soil behaviour type (Ic) and Factor of Safety (FoS)) across the study site. In 95% of the cases the critical layer occurred within two times the Height of the Free Face (HFF,). A statistical analysis of the geotechnical factors relating to the critical layer was undertaken in order to find correlations between specific deformation modes and geotechnical factors. It was found that each individual deformation mode involves a complex interplay of factors that are difficult to represent through correlative analysis. There was, however, sufficient data to derive the key factors that have affected the severity of deformation. It was concluded that stopbank damage is directly related to the presence of liquefaction in the ground materials beneath the stopbanks, but is not critical in determining the type or severity of damage, instead it is merely the triggering mechanism. Once liquefaction is triggered it is the gravity-induced deformation that causes the damage rather than the shaking duration. Lateral spreading and specifically the depositional setting was found to be the key aspect in determining the severity and type of deformation along the stopbank system. The presence or absence of abandoned or old river channels and point bar deposits was found to significantly influence the severity and type of deformation. A review of digital elevation models and old maps along the Kaiapoi River found that all of the ‘major to severe’ damage observed occurred within or directly adjacent to an abandoned river channel. Whilst a review of the geomorphology along the Avon River showed that every location within a point bar deposit suffered some form of damage, due to the depositional environment creating a deposit highly susceptible to liquefaction.
The UC CEISMIC Canterbury Earthquakes Digital Archive was built following the devastating earthquakes that hit the Canterbury region in the South Island of New Zealand from 2010 – 2012. 185 people were killed in the 6.3 magnitude earthquake of February 22nd 2011, thousands of homes and businesses were destroyed, and the local community endured over 10,000 aftershocks. The program aims to document and protect the social, cultural, and intellectual legacy of the Canterbury community for the purposes of memorialization and enabling research. The nationally federated archive currently stores 75,000 items, ranging from audio and video interviews to images and official reports. Tens of thousands more items await ingestion. Significant lessons have been learned about data integration in post-disaster contexts, including but not limited to technical architecture, governance, ingestion process, and human ethics. The archive represents a model for future resilience-oriented data integration and preservation products.
Fatal earthquakes such as that which occurred in Christchurch on February 22nd 2011, can result in survivors having difficulties with cognitively processing the event, which may be the precursor to posttraumatic stress symptoms. Trauma related dissociation has been proposed to be a mechanism related to these cognitive processing difficulties. Most research focusing on information processing and dissociation post-trauma has conducted controlled analogue studies or has not focused solely on information processing and dissociation. There is also scant research on these constructs across therapy. In response to this gap in research, two studies were developed. An association was proposed between dissociation and information processing as demonstrated by an increase in conceptual processing and a reduction in dissociation. It was predicted that an improvement in these constructs would be related to a reduction in PTSD symptoms over therapy. Study1 applied a case-study design to 5 individuals who were attending therapy for post-traumatic stress disorder in response to the trauma they had experienced from the Christchurch earthquakes. Study 2 assessed information processing and dissociation (via self and observer report) in 20 individuals who had direct exposure to the effects of the earthquake. Earthquake information processing and dissociation were assessed as they were happening nearly two year’s post-quake using correlation analyses and hierarchical regressions. The hypotheses were partially confirmed, in that an increase in conceptual processing was not shown to be associated with a reduction in dissociation. However, an increase in conceptual processing was shown to be related to trauma symptom improvement particularly for re-experiencing symptoms. In addition, study 2 demonstrated a possible relationship between trait dissociation and arousal symptoms. These findings partially support the proposed role information processing and dissociation play in the recovery from PTSD. The findings suggest that trauma related difficulties should be assessed as early as possible to resolve issues related to a delay in symptom reporting.
There is a critical strand of literature suggesting that there are no ‘natural’ disasters (Abramovitz, 2001; Anderson and Woodrow, 1998; Clarke, 2008; Hinchliffe, 2004). There are only those that leave us – the people - more or less shaken and disturbed. There may be some substance to this; for example, how many readers recall the 7.8 magnitude earthquake centred in Fiordland in July 2009? Because it was so far away from a major centre and very few people suffered any consequences, the number is likely to be far fewer than those who remember (all too vividly) the relatively smaller 7.1 magnitude Canterbury quake of September 4th 2010 and the more recent 6.3 magnitude February 22nd 2011 event. One implication of this construction of disasters is that seismic events, like those in Canterbury, are as much socio-political as they are geological. Yet, as this paper shows, the temptation in recovery is to tick boxes and rebuild rather than recover, and to focus on hard infrastructure rather than civic expertise and community involvement. In this paper I draw upon different models of community engagement and use Putnam’s (1995) notion of ‘social capital’ to frame the argument that ‘building bridges’ after a disaster is a complex blend of engineering, communication and collaboration. I then present the results of a qualitative research project undertaken after the September 4th earthquake. This research helps to illustrate the important connections between technical rebuilding, social capital, recovery processes and overall urban resilience.
As a result of the Christchurch Earthquake that occurred on 22nd February 2011 and the resultant loss of life and widespread damage, a Royal Commission of Enquiry was convened in April 2011. The Royal Commission recommended a number of significant changes to the regulation of earthquake prone building in New Zealand. Earthquake prone buildings are buildings that are deemed to be of insufficient strength to perform adequately in a moderate earthquake. In response to the Royal Commission recommendations the New Zealand Government carried out a consultative process before announcing proposed changes to the building regulations in August 2013. One of the most significant changes is the imposition of mandatory strengthening requirements for earthquake prone buildings on a national basis. This will have a significant impact on the urban fabric of most New Zealand towns and cities. The type of traditional cost benefit study carried out to date fails to measure these impacts and this paper proposes an alternative methodology based on the analysis of land use data and rating valuations. This methodology was developed and applied to a small provincial town in the form of a case study. The results of this case study and the methodology used are discussed in this paper.
The New Zealand Kellogg Rural Leaders Programme develops emerging agribusiness leaders to help shape the future of New Zealand agribusiness and rural affairs. Lincoln University has been involved with this leaders programme since 1979 when it was launched with a grant from the Kellogg Foundation, USA.At 4.35am on 4th September 2010, Canterbury was hit by an earthquake measuring 7.1 on the Richter scale. On 22nd February 2011 and 13th June 2011 a separate fault line approximately 35km from the first, ruptured to inflict two further earthquakes measuring 6.3 and 6.0 respectively. As a direct result of the February earthquake, 181 people lost their lives. Some commentators have described this series of earthquakes as the most expensive global insurance event of all time. These earthquakes and the more than 7000 associated aftershocks have had a significant physical impact on parts of Canterbury and virtually none on others. The economic, social and emotional impacts of these quakes spread across Canterbury and beyond. Waimakariri district, north of Christchurch, has reflected a similar pattern, with over 1400 houses requiring rebuild or substantial repair, millions of dollars of damage to infrastructure, and significant social issues as a result. The physical damage in Waimakiriri District was predominately in parts of Kaiapoi, and two small beach settlements, The Pines and Kairaki Beach with pockets elsewhere in the district. While the balance of the district is largely physically untouched, the economic, social, and emotional shockwaves have spread across the district. Waimakariri district consists of two main towns, Rangiora and Kaiapoi, a number of smaller urban areas and a larger rural area. It is considered mid-size in the New Zealand local government landscape. This paper will explore the actions and plans of Waimakiriri District Council (WDC) in the Emergency Management Recovery programme to provide context to allow a more detailed examination of the planning processes prior to, and subsequent to the earthquakes. This study looked at documentation produced by WDC, applicable legislation and New Zealand Emergency Management resources and other sources. Key managers and elected representatives in the WOC were interviewed, along with a selection of governmental and nongovernmental agency representatives. The interview responses enable understanding of how central Government and other local authorities can benefit from these lessons and apply them to their own planning. It is intended that this paper will assist local government organisations in New Zealand to evaluate their planning processes in light of the events of 2010/11 in Canterbury and the lessons from WDC.
The Avon-Heathcote Estuary, located in Christchurch, New Zealand, experienced coseismic deformation as a result of the February 22nd 2011 Christchurch Earthquake. The deformation is reflected as subsidence in the northern area and uplift in the southern area of the Estuary, in addition to sand volcanoes which forced up sediment throughout the floor of the Estuary altering estuary bed height and tidal flow. The first part of the research involved quantifying the change in the modern benthic foraminifera distribution as a result of the coseismic deformation caused by the February 22nd 2011 earthquake. By analysing the taxa present immediately post deformation and then the taxa present 2 years post deformation a comparison of the benthic foraminifera distribution can be made of the pre and post deformation. Both the northern and the southern areas of the Estuary were sampled to establish whether foraminifera faunas migrated landward or seaward as a result of subsidence and uplift experienced in different areas. There was no statistical change in overall species distribution in the two year time period since the coseismic deformation occurred, however, there were some noticeable changes in foraminifera distribution at BSNS-Z3 showing a landward migration of taxa. The changes that were predicted to occur as a result of the deformation of the Estuary are taking longer than expected to show up in the foraminiferal record and a longer time period is needed to establish these changes. The second stage involved establishing the modern distribution of foraminifera at Settlers Reserve in the southern area of the Avon-Heathcote Estuary by detailed sampling along a 160 m transect. Foraminifera are sensitive to environmental parameters, tidal height, grainsize, pH and salinity were recorded to evaluate the effect these parameters have on distribution. Bray-Curtis two-way cluster analysis was primarily used to assess the distribution pattern of foraminifera. The modern foraminifera distribution is comparable to that of the modern day New Zealand brackish-water benthic foraminifera distribution and includes species not yet found in other studies of the Avon-Heathcote Estuary. Differences in sampling techniques and the restricted intertidal marshland area where the transect samples were collected account for some of the differences seen between this model and past foraminifera studies. xiii The final stage involved sampling a 2.20 m core collected from Settlers Reserve and using the modern foraminiferal distribution to establish a foraminiferal history of Settlers Reserve. As foraminifera are sensitive to tidal height they may record past coseismic deformation events and the core was used to ascertain whether record of past coseismic deformation is preserved in Settlers Reserve sediments. Sampling the core for foraminifera, grainsize, trace metals and carbon material helped to build a story of estuary development. Using the modern foraminiferal distribution and the tidal height information collected, a down core model of past tidal heights was established to determine past rates of change. Foraminifera are not well preserved throughout the core, however, a sudden relative rise in sea level is recorded between 0.25 m and 0.85 m. Using trace metal and isotope analysis to develop an age profile, this sea level rise is interpreted to record coseismic subsidence associated with a palaeoseismic event in the early 1900’s. Overall, although the Avon-Heathcote Estuary experienced clear coseismic deformation as a result of the 22nd of February 2011 earthquake, modern changes in foraminiferal distribution cannot yet be tracked, however, past seismic deformation is identified in a core. The modern transect describes the foraminifera distribution which identifies species that have not been identified in the Avon-Heathcote Estuary before. This thesis enhances the current knowledge of the Avon-Heathcote Estuary and is a baseline for future studies.
The Christchurch earthquake sequence has been on-going since September 4th 2010. The largest two earthquakes, magnitude (M) 7.1 on September 4th and the M 6.3 on February 22nd 2011 caused immediate and significant damage to the city of Christchurch. As a consequence of the earthquakes, the tourism sector in the Canterbury region has been heavily impacted, with broader impacts being felt throughout the South Island. Resilient Organisations and the University of Canterbury began a series of quantitative investigations into the recovery and response of key business sectors to the earthquakes. The purpose of this study was to build on this work by exploring the outcomes of the earthquakes on the tourism sector, a critical economic driver in the region. Two postal surveys were sent to 719 tourism business managers; the first to businesses in the ‘Impact Zone’ defined as areas that experienced Modified Mercalli intensities greater than 6. The second survey was sent to the remaining businesses throughout the Canterbury region (‘Rest of Canterbury’). Response rates were 46% response for the Impact Zone, and 29% for the Rest of Canterbury. Key findings:
With the occurrence of natural disasters on the increase, major cities around the world face the potential of complete loss of infrastructure due to design guidelines that do not consider resilience in the design. With the February 22nd, 2011 earthquake in Christchurch, being the largest insured event, lessons learnt from the rebuild will be vital for the preparation of future disasters. Therefore the objective of this research is to understand the financial implications of the changes to the waste water design guidelines used throughout the five year rebuild programme of works. The research includes a study of the SCIRT alliance model selected for the delivery that is flexible enough to handle changes in the design with minimal impact on the direct cost of the rebuild works. The study further includes the analysis and compares the impact of the three different guidelines on maintenance and replacement cost over the waste water pipe asset life. The research concludes that with the varying ground conditions in Christchurch and also the wide variety of materials in use in the waste water network up to the start of the CES, the rebuild was not a ‘one size fits all’ approach.
Over 900 buildings in the Christchurch central business district and 10,000 residential homes were demolished following the 22nd of February 2011 Canterbury earthquake, significantly disrupting the rebuild progress. This study looks to quantify the time required for demolitions during this event which will be useful for future earthquake recovery planning. This was done using the Canterbury Earthquake Recovery Authority (CERA) demolition database, which allowed an in-depth look into the duration of each phase of the demolition process. The effect of building location, building height, and the stakeholder which initiated the demolition process (i.e. building owner or CERA) was investigated. The demolition process comprises of five phases; (i) decision making, (ii) procurement and planning, (iii) demolition, (iv) site clean-up, and (v) completion certification. It was found that the time required to decide to demolish the building made up majority of the total demolition duration. Demolition projects initiated by CERA had longer procurement and planning durations, but was quicker in other phases. Demolished buildings in the suburbs had a longer decision making duration, but had little effect on other phases of the demolition process. The decision making and procurement and planning phases of the demolition process were shorter for taller buildings, though the other phases took longer. Fragility functions for the duration of each phase in the demolition process are provided for the various categories of buildings for use in future studies.
This thesis investigates the relationship between the apocalyptic narrative and the postmodern novel. It explores and builds on Patricia Waugh‟s hypothesis in Practising Postmodernism: Reading Modernism (1992) which suggests that that the postmodern is characterised by an apocalyptic sense of crisis, and argues that there is in fact a strong relationship between the apocalyptic and the postmodern. It does so through an exploration of apocalyptic narratives and themes in five postmodern novels. It also draws on additional supporting material which includes literary and cultural theory and criticism, as well as historical theory. In using the novel as a medium through which to explore apocalyptic narratives, this thesis both assumes and affirms the novel‟s importance as a cultural artefact which reflects the concerns of the age in which it is written. I suggest that each of the novels discussed in this thesis demonstrates the close relationship between the apocalyptic and the postmodern through society‟s concern over the direction of history, the validity of meta-narratives, and other cultural phenomenon, such as war, the development of nuclear weaponry, and terrorism. Although the scope of this thesis is largely confined to the historical-cultural epoch known as postmodernity, it also draws on literature and cultural criticism from earlier periods so as to provide a more comprehensive framework for investigating apocalyptic ideas and their importance inside the postmodern novel. A number of modernist writers are therefore referred to or quoted throughout this thesis, as are other important thinkers from preceding periods whose ideas are especially pertinent. The present thesis was researched and written between March 2010 and August 2011 and is dedicated to all of those people who lost their lives in the apocalyptic events of the February 22nd Christchurch earthquake.
The Canterbury earthquake and aftershock sequence in New Zealand during 2010-2011 subjected the city’s structures to a significant accumulated cyclic demand and raised significant questions regarding the low-cycle fatigue demands imposed upon the structures. There is a significant challenge to quantify the level of cumulative demand imposed on structures and to assess the percentage of a structure's fatigue life that has been consumed as a result of this earthquake sequence. It is important to be able to quantify the cumulative demand to determine how a building will perform in a subsequent large earthquake and inform repair and re-occupancy decisions. This paper investigates the cumulative fatigue demand for a structure located within the Christchurch Central Business District (CBD). Time history analysis and equivalent cycle counting methods are applied across the Canterbury earthquake sequence, using key events from September 4th 2010 and February 22nd , 2011 main shocks. The estimate of the cumulative fatigue demand is then compared to the expected capacity of a case study reinforced concrete bridge pier, to undertake a structure-specific fatigue assessment. The analysis is undertaken to approximate the portion of the structural fatigue capacity that has been consumed, and how much residual capacity remains. Results are assessed for recordings at the four Christchurch central city strong motion recording sites installed by the GeoNet programme, to provide an estimate of variation in results. The computed cyclic demand results are compared to code-based design methods and as assessment of the inelastic displacement demand of the reinforcing steel. Results are also presented in a fragility context where a de minimis (inconsequential), irreparable damage and full fatigue fracture are defined to provide a probabilistic assessment of the fatigue damage incurred. This methodology can provide input into the overall assessment of fatigue demands and residual capacity.
When the devastating 6.3 magnitude earthquake hit Christchurch, Aotearoa New Zealand, at 12.51pm on 22nd February 2011, the psychological and physical landscape was irrevocably changed. In the days and weeks following the disaster communities were isolated due to failed infrastructure, continuing aftershocks and the extensive search and rescue effort which focussed resources on the central business district. In such moments the resilience of a community is truly tested. This research discusses the role of grassroots community groups in facilitating community resilience during the Christchurch 2010/11 earthquakes and the role of place in doing so. I argue that place specific strategies for urban resilience need to be enacted from a grassroots level while being supported by broader policies and agencies. Using a case study of Project Lyttelton – a group aspiring towards a resilient sustainable future who were caught at the epicentre of the February earthquake – I demonstrate the role of a community group in creating resilience through self-organised place specific action during a disaster. The group provided emotional care, basic facilities and rebuilding assistance to the residents of Lyttelton, proving to be an invaluable asset. These actions are closely linked to the characteristics of social support and social learning that have been identified as important to socio-ecological resilience. In addition this research will seek to understand and explore the nuances of place and identity and its role in shaping resilience to such dis-placing events. Drawing on community narratives of the displacement of place identity, the potential for a progressive sense of place as instigated by local groups will be investigated as an avenue for adaptation by communities at risk of disaster and place destabilisation.
The magnitude Mw 6.2 earthquake of February 22nd 2011 that struck beneath the city of Christchurch, New Zealand, caused widespread damage and was particularly destructive to the Central Business District (CBD). The shaking caused major damage, including collapses of structures, and initiated ground failure in the form of soil liquefaction and consequent effects such as sand boils, surface flooding, large differential settlements of buildings and lateral spreading of ground towards rivers were observed. A research project underway at the University of Canterbury to characterise the engineering behaviour of the soils in the region was influenced by this event to focus on the performance of the highly variable ground conditions in the CBD. This paper outlines the methodology of this research to characterise the key soil horizons that underlie the CBD that influenced the performance of important structures during the recent earthquakes, and will influence the performance of the rebuilt city centre under future events. The methodology follows post-earthquake reconnaissance in the central city, a desk study on ground conditions, site selection, mobilisation of a post-earthquake ground investigation incorporating the cone penetration test (CPT), borehole drilling, shear wave velocity profiling and Gel-push sampling followed by a programme of laboratory testing including monotonic and cyclic testing of the soils obtained in the investigation. The research is timely and aims to inform the impending rebuild, with appropriate information on the soils response to dynamic loading, and the influence this has on the performance of structures with various foundation forms.
The Canterbury region of New Zealand was shaken by major earthquakes on the 4th September 2010 and 22nd February 2011. The quakes caused 185 fatalities and extensive land, infrastructure and building damage, particularly in the Eastern suburbs of Christchurch city. Almost 450 ha of residential and public land was designated as a ‘Red Zone’ unsuitable for residential redevelopment because land damage was so significant, engineering solutions were uncertain, and repairs would be protracted. Subsequent demolition of all housing and infrastructure in the area has left a blank canvas of land stretching along the Avon River corridor from the CBD to the sea. Initially the Government’s official – but enormously controversial – position was that this land would be cleared and lie fallow until engineering solutions could be found that enabled residential redevelopment. This paper presents an application of a choice experiment (CE) that identified and assessed Christchurch residents’ preferences for different land use options of this Red Zone. Results demonstrated strong public support for the development of a recreational reserve comprising a unique natural environment with native fauna and flora, healthy wetlands and rivers, and recreational opportunities that align with this vision. By highlighting the value of a range of alternatives, the CE provided a platform for public participation and expanded the conversational terrain upon which redevelopment policy took place. We conclude the method has value for land use decision-making beyond the disaster recovery context.
This report presents research on the affects of the Ōtautahi/Christchurch earthquakes of 2010 to 2012 on the city’s Tangata Whaiora community, ‘people seeking health’ as Māori frame mental health clients. Drawing on the voices of 39 participants of a Kaupapa Māori provider (Te Awa o te Ora), this report presents extended quotes from Tangata Whaiora, their support staff (many of whom are Tangata Whaiora), and managers as they speak of the events, their experiences, and support that sustained them in recoveries of well-being through the worse disaster in Aotearoa/New Zealand in three generations. Ōtautahi contains a significant urban Māori population, many living in suburbs that were seriously impacted by the earthquakes that began before dawn on September 4th, 2010, and continued throughout 2011 and 2012. The most damaging event occurred on February 22nd, 2011, and killed 185 people and severely damaged the CBD as well as many thousands of homes. The thousands of aftershocks delayed the rebuilding of homes and infrastructure and exacerbated the stress and dislocation felt by residents. The tensions and disorder continue for numerous residents into 2014 and it will be many years before full social and physical recovery can be expected. This report presents extended excerpts from the interviews of Tangata Whaiora and their support staff. Their stories of survival through the disaster reinforce themes of community and whānau while emphasising the reality that a significant number of Tangata Whaiora do not or cannot draw on this supports. The ongoing need for focused responses in the area of housing and accommodation, sufficiently resourced psycho-social support, and the value of Kaupapa Māori provision for Māori and non-Māori mental health clients cannot be overstated. The report also collates advice from participants to other Tangata Whaiora, their whānau, providers and indeed all residents of places subject to irregular but potentially devastating disaster. Much of this advice is relevant for more daily challenges and should not be underestimated despite its simplicity.
The development of Digital City technologies to manage and visualise spatial information has increasingly become a focus of the research community, and application by city authorities. Traditionally, the Geographic Information Systems (GIS) and Building Information Models (BIM) underlying Digital Cities have been used independently. However, integrating GIS and BIM into a single platform provides benefits for project and asset management, and is applicable to a range of issues. One of these benefits is the means to access and analyse large datasets describing the built environment, in order to characterise urban risk from and resilience to natural hazards. The aim of this thesis is to further explore methodologies of integration in two distinct areas. The first, integration through connectivity of heterogeneous datasets where GIS spatial infrastructure data is merged with 3D BIM building data to create a digital twin. Secondly, integration through analysis whereby data from the digital twin are extracted and integrated with computational models. To achieve this, a workflow was developed to identify the required datasets of a digital twin, and develop a process of integrating those datasets through a combination of; semi-autonomous conversion, translation and extension of data; and semantic web and services-based processes. Through use of a designed schema, the data were streamed in a homogenous format in a web-based platform. To demonstrate the value of this workflow with respect to urban risk and resilience, the process was applied to the Taiora: Queen Elizabeth II recreation and sports centre in eastern Christchurch, New Zealand. After integration of as-built GIS and BIM datasets, targeted data extraction was implemented, with outputs tailored for analysis in an infrastructure serviceability loss model, which assessed potable water network performance in the 22nd February 2011 Christchurch Earthquake. Using the same earthquake conditions as the serviceability loss model, performance of infrastructure assets in service at the time of the 22nd February 2011 Christchurch Earthquake was compared to new assets rebuilt at the site, post-earthquake. Due to improved potable water infrastructure resilience resulting from installation of ductile piles, a decrease of 35.5% in the probability of service loss was estimated in the serviceability loss model. To complete the workflow, the results from the external analysis were uploaded to the web-based platform. One of the more significant outcomes from the workflow was the identification of a lack of mandated metadata standards for fittings/valves connecting a building to private laterals. Whilst visually the GIS and BIM data show the building and pipes as connected, the semantic data does not include this connectivity relationship. This has no material impact on the current serviceability loss model as it is not one of the defined parameters. However, a proposed modification to the model would utilise the metadata to further assess the physical connection robustness, and increase the number of variables for estimating probability of service loss. This thesis has made a methodological contribution to urban resilience analysis by demonstrating how readily available up-to-date building and infrastructure data can be integrated, and with tailored extraction from a Digital City platform, be used for disaster impact analysis in an external computational engine, with results in turn imported and visualised in the Digital City platform. The workflow demonstrated that translation and integration of data would be more successful if a regional/national mandate was implemented for the submission of consent documentation in a specified standard BIM format. The results of this thesis have identified that the key to ensuring the success of an integrated tool lies in the initial workflow required to safeguard that all data can be either captured or translated in an interoperable format.
The development of Digital City technologies to manage and visualise spatial information has increasingly become a focus of the research community, and application by city authorities. Traditionally, the Geographic Information Systems (GIS) and Building Information Models (BIM) underlying Digital Cities have been used independently. However, integrating GIS and BIM into a single platform provides benefits for project and asset management, and is applicable to a range of issues. One of these benefits is the means to access and analyse large datasets describing the built environment, in order to characterise urban risk from and resilience to natural hazards. The aim of this thesis is to further explore methodologies of integration in two distinct areas. The first, integration through connectivity of heterogeneous datasets where GIS spatial infrastructure data is merged with 3D BIM building data to create a digital twin. Secondly, integration through analysis whereby data from the digital twin are extracted and integrated with computational models. To achieve this, a workflow was developed to identify the required datasets of a digital twin, and develop a process of integrating those datasets through a combination of; semi-autonomous conversion, translation and extension of data; and semantic web and services-based processes. Through use of a designed schema, the data were streamed in a homogenous format in a web-based platform. To demonstrate the value of this workflow with respect to urban risk and resilience, the process was applied to the Taiora: Queen Elizabeth II recreation and sports centre in eastern Christchurch, New Zealand. After integration of as-built GIS and BIM datasets, targeted data extraction was implemented, with outputs tailored for analysis in an infrastructure serviceability loss model, which assessed potable water network performance in the 22nd February 2011 Christchurch Earthquake. Using the same earthquake conditions as the serviceability loss model, performance of infrastructure assets in service at the time of the 22nd February 2011 Christchurch Earthquake was compared to new assets rebuilt at the site, post-earthquake. Due to improved potable water infrastructure resilience resulting from installation of ductile piles, a decrease of 35.5% in the probability of service loss was estimated in the serviceability loss model. To complete the workflow, the results from the external analysis were uploaded to the web-based platform. One of the more significant outcomes from the workflow was the identification of a lack of mandated metadata standards for fittings/valves connecting a building to private laterals. Whilst visually the GIS and BIM data show the building and pipes as connected, the semantic data does not include this connectivity relationship. This has no material impact on the current serviceability loss model as it is not one of the defined parameters. However, a proposed modification to the model would utilise the metadata to further assess the physical connection robustness, and increase the number of variables for estimating probability of service loss. This thesis has made a methodological contribution to urban resilience analysis by demonstrating how readily available up-to-date building and infrastructure data can be integrated, and with tailored extraction from a Digital City platform, be used for disaster impact analysis in an external computational engine, with results in turn imported and visualised in the Digital City platform. The workflow demonstrated that translation and integration of data would be more successful if a regional/national mandate was implemented for the submission of consent documentation in a specified standard BIM format. The results of this thesis have identified that the key to ensuring the success of an integrated tool lies in the initial workflow required to safeguard that all data can be either captured or translated in an interoperable format.
4th September 2010 a 7.1 magnitude earthquake strikes near Christchurch, New Zealand’s second largest city of approximately 370,000 people. This is followed by a 6.3 magnitude quake on 22nd February 2011 and a 6.4 on 13th June. In February 181 people died and a state of national emergency was declared from 23 February to 30th April. Urban Search and Rescue teams with 150 personnel from New Zealand and 429 from overseas worked tirelessly in addition to Army, Police and Fire services. Within the central business district 1,000 buildings (of 4,000) are expected to be demolished. An estimated 10,000 houses require demolition and over 100,000 were damaged. Meanwhile the over 7,000 aftershocks have become part of the “new normal” for us all. During this time how have libraries supported their staff? What changes have been made to services? What are the resourcing opportunities? This presentation will provide a personal view from Lincoln University, Te Whare Wanaka o Aoraki, Library Teaching and Learning. Lincoln is New Zealand's third oldest university having been founded in 1878. Publicly owned and operated it is New Zealand's specialist land-based university. Lincoln is based on the Canterbury Plains, 22 kilometres south of Christchurch. On campus there was mostly minor damage to buildings while in the Library 200,000 volumes were thrown from the shelves. I will focus on the experiences of the Disaster Team and on our experiences with hosting temporarily displaced staff and students from the Christchurch Polytechnic Institute of Technology, Library, Learning & Information Services. Experiences from two other institutions will be highlighted: Christchurch City Libraries, Ngā Kete Wānanga-o-Ōtautahi. Focusing on the Māori Services Team and the Ngā Pounamu Māori and Ngāi Tahu collections. The Central library located within the red zone cordon has been closed since February, the Central library held the Ngā Pounamu Māori and Ngai Tahu collections, the largest Māori collections in the Christchurch public library network. The lack of access to these collections changed the way the Māori Services Team, part of the larger Programmes, Events and Learning Team at Christchurch City Libraries were able to provide services to their community resulting in new innovative outreach programmes and a focus on promotion of online resources. On 19th December the “temporary” new and smaller Central library Peterborough opened. The retrieved Ngā Pounamu Māori and Ngai Tahu collections "Ngā rakau teitei e iwa”, have since been re-housed and are once again available for use by the public. Te Rūnanga o Ngāi Tahu. This organisation, established by the Te Rūnanga o Ngāi Tahu Act 1996, services the statutory rights for the people of Ngāi Tahu descent and ensures that the benefits of their Treaty Claim Settlement are enjoyed by Ngāi Tahu now and in the future. Ngāi Tahu are the indigenous Māori people of the southern islands of New Zealand - Te Waipounamu. The iwi (people) hold the rangatiratanga or tribal authority to over 80 per cent of the South Island. With their headquarters based in the central business they have also had to be relocated to temporary facilities. This included their library/archive collection of print resources, art works and taonga (cultural treasures).
This thesis is about many things, not least of all the September 4th 2010 and February 22nd 2011 earthquakes that shook Christchurch, New Zealand. A city was shaken, events which worked to lay open the normally invisible yet vital objects, processes and technologies which are the focus of inquiry: the sewers, pipes, pumps, the digital technologies, the land and politics which constitute the Christchurch wastewater networks. The thesis is an eclectic mix drawing together methods and concepts from Bruno Latour, John Law, Giles Deleuze and Felix Guattari, Nigel Thrift, Donna Haraway and Patrick Joyce. It is an exploration of how the technologies and objects of sanitation perform the city, and how such things which are normally hidden and obscured, are made visible. The question of visibility is also turned toward the research itself: how does one observe, and describe? How are sociological visibilities constructed? Through the research, the encountering of objects in the field, the processes of method, the pedagogy of concepts, and the construction of risk, the thesis comes to be understood as a particular kind of social scientific artefact which assembles four different accounts: the first regards the construction of visibility; the second explores Christchurch city from the control room where the urban sanitary infrastructures are monitored; the third chapter looks at the formatted and embodied practices which emerge with the correlation of the city and sanitation; the fourth looks at the changing politics of a city grappling with severely damaged essential services, land and structures. The final chapter considers how the differences between romantic and baroque sensibilities mean that these four accounts elicit knowing not through smoothness or uniformity, but in partiality and non-coherence. This thesis is about pipes, pump stations, and treatment plants; about the effluent of a city; about the messiness of social science when confronted by the equally messy world of wastewater.
This project looks at how destroyed architecture, although physically lost, fundamentally continues to exist within human memories as a non-physical entity. The site chosen is Avonside Girls’ High School in Christchurch, New Zealand, a school heavily damaged during the February 22nd earthquake in 2011. The project focuses on the Main Block, a 1930s masonry building which had always been a symbol for the school and its alumni. The key theories relevant to this are studies on non-material architecture and memory as these subjects investigate the relationship between conceptual idea and the triggering of it. This research aims to study how to fortify a thought-based architecture against neglect, similar to the retrofitting of physical structures. In doing so, the importance of the emotive realm of architecture and the idea behind a building (as opposed to the built component itself) is further validated, promoting more broadminded stances regarding the significance of the idea over the object. A new method for disaster recovery and addressing trauma from lost architecture is also acquired. Factors regarding advanced structural systems and programmes are not covered within the scope of this research because the project instead explores issues regarding the boundaries between the immaterial and material. The project methodology involves communicating a narrative derived from the memories alumni and staff members have of the old school block. The approach for portraying the narrative is based on a list of strategies obtained from case studies. The final product of the research is a new design for the high school, conveyed through a set of atmospheric drawings that cross-examines the boundaries between the physical and non-physical realms by representing the version of the school that exists solely within memories.
For the people of Christchurch and its wider environs of Canterbury in New Zealand, the 4th of September 2010 earthquake and the subsequent aftershocks were daunting. To then experience a more deadly earthquake five months later on the 22nd of February 2011 was, for the majority, overwhelming. A total of 185 people were killed and the earthquake and continuing aftershocks caused widespread damage to properties, especially in the central city and eastern suburbs. A growing body of literature consistently documents the negative impact of experiencing natural disasters on existing psychological disorders. As well, several studies have identified positive coping strategies which can be used in response to adversities, including reliance on spiritual and cultural beliefs as well as developing resilience and social support. The lifetime prevalence of severe mental health disorders such as posttraumatic stress disorder (PTSD) occurring as a result of experiencing natural disasters in the general population is low. However, members of refugee communities who were among those affected by these earthquakes, as well as having a past history of experiencing traumatic events, were likely to have an increased vulnerability. The current study was undertaken to investigate the relevance to Canterbury refugee communities of the recent Canterbury Earthquake Recovery Authority (CERA) draft recovery strategy for Christchurch post-earthquakes. This was accomplished by interviewing key informants who worked closely with refugee communities. These participants were drawn from different agencies in Christchurch including Refugee Resettlement Services, the Canterbury Refugee Council, CERA, and health promotion and primary healthcare organisations, in order to obtain the views of people who have comprehensive knowledge of refugee communities as well as expertise in local mainstream services. The findings from the semi-structured interviews were analysed using qualitative thematic analysis to identify common themes raised by the participants. The key informants described CERA’s draft recovery strategy as a significant document which highlighted the key aspects of recovery post disaster. Many key informants identified concerns regarding the practicality of the draft recovery strategy. For the refugee communities, some of those concerns included the short consultation period for the implementation phase of the draft recovery strategy, and issues surrounding communication and collaboration between refugee agencies involved in the recovery. This study draws attention to the importance of communication and collaboration during recovery, especially in the social reconstruction phase following a disaster, for all citizens but most especially for refugee communities.
The city of Ōtautahi/Christchurch experienced a series of earthquakes that began on September 4th, 2010. The most damaging event occurred on February 22nd, 2011 but significant earthquakes also occurred on June 13th and December 23rd with aftershocks still occurring well into 2012. The resulting disaster is the second deadliest natural disaster in New Zealand’s history with 185 deaths. During 2011 the Canterbury earthquakes were one of the costliest disasters worldwide with an expected cost of up to $NZ30 billion. Hundreds of commercial buildings and thousands of houses have been destroyed or are to be demolished and extensive repairs are needed for infrastructure to over 100,000 homes. As many as 8,900 people simply abandoned their homes and left the city in the first few months after the February event (Newell, 2012), and as many as 50,000 may leave during 2012. In particular, young whānau and single young women comprised a disproportionate number of these migrants, with evidence of a general movement to the North Island. Te Puni Kōkiri sought a mix of quantitative and qualitative research to examine the social and economic impacts of the Christchurch earthquakes on Māori and their whānau. The result of this work will be a collection of evidence to inform policy to support and assist Māori and their whānau during the recovery/rebuild phases. To that end, this report triangulates available statistical and geographical information with qualitative data gathered over 2010 and 2011 by a series of interviews conducted with Māori who experienced the dramatic events associated with the earthquakes. A Māori research team at Lincoln University was commissioned to undertake the research as they were already engaged in transdisciplinary research (began in the May 2010), that focused on quickly gathering data from a range of Māori who experienced the disaster, including relevant economic, environmental, social and cultural factors in the response and recovery of Māori to these events. Participants for the qualitative research were drawn from Māori whānau who both stayed and left the city. Further data was available from ongoing projects and networks that the Lincoln research team was already involved in, including interviews with Māori first responders and managers operating in the CBD on the day of the February event. Some limited data is also available from younger members of affected whānau. Māori in Ōtautahi/Christchurch City have exhibited their own culturally-attuned collective responses to the disaster. However, it is difficult to ascertain Māori demographic changes due to a lack of robust statistical frameworks but Māori outward migration from the city is estimated to range between 560 and 1,100 people. The mobility displayed by Māori demonstrates an important but unquantified response by whānau to this disaster, with emigration to Australia presenting an attractive option for young Māori, an entrenched phenomenon that correlates to cyclical downturns and the long-term decline of the New Zealand economy. It is estimated that at least 315 Māori have emigrated from the Canterbury region to Australia post-quake, although the disaster itself may be only one of a series of events that has prompted such a decision. Māori children made up more than one in four of the net loss of children aged 6 to 15 years enrolled in schools in Greater Christchurch over the year to June 2011. Research literature identifies depression affecting a small but significant number of children one to two years post-disaster and points to increasing clinical and organisational demands for Māori and other residents of the city. For those residents in the eastern or coastal suburbs – home to many of the city’s Māori population - severe damage to housing, schools, shops, infrastructure, and streets has meant disruption to their lives, children’s schooling, employment, and community functioning. Ongoing abandonment of homes by many has meant a growing sense of unease and loss of security, exacerbated by arson, burglaries, increased drinking, a stalled local and national economy, and general confusion about the city’s future. Māori cultural resilience has enabled a considerable network of people, institutions, and resources being available to Māori , most noticeably through marae and their integral roles of housing, as a coordinating hub, and their arguing for the wider affected communities of Christchurch. Relevant disaster responses need to be discussed within whānau, kōhanga, kura, businesses, communities, and wider neighbourhoods. Comprehensive disaster management plans need to be drafted for all iwi in collaboration with central government, regional, and city or town councils. Overall, Māori are remarkably philosophical about the effects of the disaster, with many proudly relishing their roles in what is clearly a historic event of great significance to the city and country. Most believe that ‘being Māori’ has helped cope with the disaster, although for some this draws on a collective history of poverty and marginalisation, features that contribute to the vulnerability of Māori to such events. While the recovery and rebuild phases offer considerable options for Māori and iwi, with Ngāi Tahu set to play an important stakeholder in infrastructural, residential, and commercial developments, some risk and considerable unknowns are evident. Considerable numbers of Māori may migrate into the Canterbury region for employment in the rebuild, and trades training strategies have already been established. With many iwi now increasingly investing in property, the risks from significant earthquakes are now more transparent, not least to insurers and the reinsurance sector. Iwi authorities need to be appraised of insurance issues and ensure sufficient coverage exists and investments and developments are undertaken with a clear understanding of the risks from natural hazards and exposure to future disasters.
Picture this, you are relaxing at home enjoying the afternoon sun. It is another beautiful Christchurch day in late 2017. There is a knock at the door, you’ve been expecting it. It is a member of the Christchurch Health and Development Study, here to conduct your prearranged interview. The interview request did not come as a surprise of course, you have been participating in these interviews yourself sporadically throughout your adult life, and prior to that you attended many alongside your parents. In fact, you have been answering the studies interview your whole life. Transcripts of these interviews sit in the studies database alongside copies of school reports, health records and a wealth of other information. It has been this way since birth, since your mother was approached back in 1977, not long after you had arrived in this world, and asked if she would consent to participating in the study. She, along with many other Cantabrian new mothers from that year, agreed and the Christchurch Health and Development Study was born. Since then, these interviews have become a matter of routine for you. As life went on many things changed, but one thing that was constant was the sporadic visit from an interviewer of the study. The current interview is a little different from most of the others, however. Last time an interviewer visited in 2012, you were asked if you would like to conduct an earthquake-specific interview, you agreed. This time, the same question was asked. Why? Well because you were there that day of course. The day of the 22nd February 2011 when a major earthquake struck Canterbury. You were there in the centre of the city as buildings came crashing down and people ran for safety. You were there for the chaos. Your knee dully aches, it never did quite heal properly and strangely seems to flare up whenever you think back to that day. A lasting reminder. It is a difficult subject, but you agree to the second earthquake-specific interview. You understand the purpose of the study, and the value of the data collected. You take a sip of the cup of tea politely made upon the interviewer’s arrival, lean back into the comfort of your couch and cast your mind back to that fateful day. So, what does this study mean? Why still participate, all these years later? Over time it has become more apparent as to how valuable this information could be, considering all the experiences through the life course, and to think of the experiences that others in the cohort have had too. How differently have events affected people from all walks of life, who just so happened to be born within the same few months. We can use the data from this study to better understand situations when using life course characteristics which can hopefully influence decision making and population health within New Zealand.
On the 22nd of February, 2011 the city of Christchurch, New Zealand was crippled by a colossal earthquake. 185 people were killed, thousands injured and what remained was a city left in destruction and ruin. Thousands of Christchurch properties and buildings were left damaged beyond repair and the rich historical architecture of the Canterbury region had suffered irreparably. This research will conduct an investigation into whether the use of mixed reality can aid in liberating Christchurch’s rich architectural heritage when applied to the context of destructed buildings within Christchurch. The aim of this thesis is to formulate a narrative around the embodiment of mixed reality when subjected to the fragmentary historical architecture of Christchurch. Mixed reality will aspire to act as the defining ligature that holds the past, present and future of Christchurch’s architectural heritage intact as if it is all part of the same continuum. This thesis will focus on the design of a memorial museum within a heavily damaged historical trust registered building due to the Christchurch earthquake. It is important and relevant to conceive the idea of such a design as history is what makes everything we know. The memories of the past, the being of the now and the projection of the future is the basis and fundamental imperative in honouring the city and people of Christchurch. Using the technologies of Mixed Reality and the realm of its counter parts the memorial museum will be a definitive proposition of desire in providing a psychological and physical understanding towards a better Christchurch, for the people of Christchurch. This thesis serves to explore the renovation possibilities of the Canterbury provincial council building in its destructed state to produce a memorial museum for the Christchurch earthquake. The design seeks to mummify the building in its raw state that sets and develops the narrative through the spaces. The design intervention is kept at a required minimum and in doing so manifests a concentrated eloquence to the derelict space. The interior architecture unlocks the expression of history and time encompassed within a destructive and industrialised architectural dialogue. History is the inhabitant of the building, and using the physical and virtual worlds it can be set free. This thesis informs a design for a museum in central Christchurch that celebrates and informs the public on past, present and future heritage aspects of Christchurch city. Using mixed reality technologies the spatial layout inside will be a direct effect of the mixed reality used and the exploration of the physical and digital heritage aspects of Christchurch. The use of technology in today’s world is so prevalent that incorporating it into a memorial museum for Christchurch would not only be interesting and exploratory but also offer a sense of pushing forward and striving beyond for a newer, fresher Christchurch. The memorial museum will showcase a range of different exhibitions that formulate around the devastating Christchurch earthquake. Using mixed reality technologies these exhibitions will dictate the spaces inside dependant on their various applications of mixed reality as a technology for architecture. Research will include; what the people of Canterbury are most dear to in regards to Christchurch’s historical environment; the use of mixed reality to visualise digital heritage, and the combination of the physical and digital to serve as an architectural mediation between what was, what is and what there could be.
One of the less understood geotechnical responses to the cyclic loading from the MW6.2 Christchurch Earthquake, on the 22nd of February 2011, is the fissuring in the loessial soil-mantled, footslope positions of the north-facing valleys of the Port Hills. The fissures are characterized by mostly horizontal offset (≤500mm), with minor vertical displacement (≤300mm), and they extend along both sides of valleys for several hundred metres in an approximately contour-parallel orientation. The fissure traces correspond to extensional features mapped in other studies. Previous studies have suggested that the fissures are the headscarps of incipient landslides, but the surface and subsurface features are not typical of landslide movement. Whilst there are some features that correlate with landslide movement, there are many features that contradict the landslide movement hypothesis. Of critical importance to this investigation was the fact that there are no landslide flanks, there has been no basal shear surface found, there is little deformation in the so-called ‘landslide body’, and there have been no recorded zones of low shear strength in the soil deposit that are indicative of a basal shear surface. This thesis is a detailed geotechnical study on the fissures along part of Ramahana Road in the Hillsborough Valley, Christchurch. Shallow and deep investigation methods found that the predominant soil is loess-colluvium, to depths of ~20m, and this soil has variable geotechnical characteristics depending on the layer sampled. The factor that has the most influence on shear strength was found to be the moisture content. Direct shear-box testing of disturbed, recompacted loess-colluvium found that the soil had a cohesion of 35-65kPa and a friction angle of 38-43° when the soil moisture content was at 8-10%. However when the moisture content was at 19-20% the soil’s cohesion decreased to 3-5kPa and its friction angle decreased to 33-38°, this moisture content is at or slightly above the plastic limit. An electrical resistivity geophysical survey was conducted perpendicular to multiple fissure traces and through the compressional zone at 17 Ramahana Road. The electrical resistivity line found that there was an area of high resistivity at the toe of the slope, and an area of high conductivity downslope of this and at greater depths. This area correlated to the compressional zone recorded by previous studies. Moisture content testing of the soil in these locations showed that the soil in the resistive area was relatively dry (9%) compared to the surrounding soil (13%), whilst the soil in the conductive area was relatively wet (22%)compared to the surrounding soil (19%). Density tests of the soil in the compressional zone recorded that the resistive area had a higher dry density than the surrounding soil (~1790 kg/m3 compared to ~1650 kg/m3). New springs arose downslope of the compressional zone contemporaneously with the fissures, and it is interpreted that these have arisen from increased hydraulic head in the Banks Peninsula bedrock aquifer system, and earthquake induced-bedrock fracturing. A test pit was dug across an infilled fissure trace at 17 Ramahana Road to a depth of 3m. The fissure trace had an aperture of 450-470mm at the ground surface, but it gradually lost aperture with depth until 2.0-2.1m where it became a segmented fissure trace with 1-2mm aperture. A mixed-colluvium layer was intercepted by the fissure trace at 2.4m depth, and there was no observable vertical offset of this layer. The fissure trace was at an angle of 78° at the ground surface, but it also flattened with depth, which gave it a slightly curved appearance. The fissure trace was at an assumed angle of 40-50° near the base of the test pit. Rotational slide, translational slide and lateral spread landslide movement types were compared and contrasted as possibilities for landslide movement types, whilst an alternative hypothesis was offered that the fissures are tensile failures with a quasi-toppling motion involving a cohesive block of loessial soil moving outwards from the slope, with an accommodating compressional strain in the lower less cohesive soil. The mechanisms behind this movement are suggested to be the horizontal earthquake inertia forces from the Christchurch Earthquake, the static shear stress of the slope, and bedrock uplift of the Port Hills in relation to the subsidence of the Christchurch city flatlands. Extremely high PGA is considered to be a prerequisite to the fissure trace development, and these can only be induced in the Hillsborough Valley from a Port Hills Fault rupture, which has a recurrence interval of ~10,000 years. The current understanding of how the loess-colluvium soil would behave under cyclic loading is limited, and the mechanisms behind the suggested movement type are not completely understood. Further research is needed to confirm the proposed mechanism of the fissure traces. Laboratory tests such as the cyclic triaxial and cyclic shear test would be beneficial in future research to quantitatively test how the soil behaves under cyclic loading at various moisture contents and clay contents, and centrifuge experiments would be of great use to qualitatively test the suggested mode of movement in the loessial soil.
Following the 22nd February 2011, Mw 6.2 earthquake located along a previously unknown fault beneath the Port Hills of Christchurch, surface cracking was identified in contour parallel locations within fill material at Quarry Road on the lower slopes of Mount Pleasant. GNS Science, in the role of advisor to the Christchurch City Council, concluded that these cracks were a part of a potential rotational mass movement (named zone 11A) within the fill and airfall loess material present. However, a lack of field evidence for slope instability and an absence of laboratory geotechnical data on which slope stability analysis was based, suggested this conclusion is potentially incorrect. It was hypothesised that ground cracking was in fact due to earthquake shaking, and not mass movement within the slope, thus forming the basis of this study. Three soil units were identified during surface and subsurface investigations at Quarry Road: fill derived from quarry operations in the adjacent St. Andrews Quarry (between 1893 and 1913), a buried topsoil, and underlying in-situ airfall loess. The fill material was identified by the presence of organic-rich topsoil “clods” that were irregular in both size (∼10 – 200 mm) and shape, with variable thicknesses of 1 – 10 m. Maximum thickness, as indicated by drill holes and geophysical survey lines, was identified below 6 Quarry Road and 7 The Brae where it is thought to infill a pre-existing gully formed in the underlying airfall loess. Bearing strength of the fill consistently exceeded 300 kPa ultimate below ∼500 mm depth. The buried topsoil was 200 – 300 mm thick, and normally displayed a lower bearing strength when encountered, but not below 300 kPa ultimate (3 – 11 blows per 100mm or ≥100 kPa allowable). In-situ airfall loess stood vertically in outcrop due to its characteristic high dry strength and also showed Scala penetrometer values of 6 – 20+ blows per 100 mm (450 – ≥1000 kPa ultimate). All soils were described as being moist to dry during subsurface investigations, with no groundwater table identified during any investigation into volcanic bedrock. In-situ moisture contents were established using bulk disturbed samples from hand augers and test pitting. Average moisture contents were low at 9% within the fill, 11 % within the buried topsoil, and 8% within the airfall loess: all were below the associated average plastic limit of 17, 15, and 16, respectively, determined during Atterberg limit analysis. Particle size distributions, identified using the sieve and pipette method, were similar between the three soil units with 11 – 20 % clay, 62 – 78 % silt, and 11 – 20 % fine sand. Using these results and the NZGS soil classification, the loess derived fill and in-situ airfall loess are termed SILT with some clay and sand, and the buried topsoil is SILT with minor clay and sand. Dispersivity of the units was found using the Emerson crumb test, which established that the fill can be non- to completely dispersive (score 0 – 4). The buried topsoil was always non-dispersive (score 0), and airfall loess completely dispersive (score 4). Values for cohesion (c) and internal friction angle (φ) of the three soil units were established using the direct shear box at field moisture contents. Results showed all soil units had high shear strengths at the moisture contents tested (c = 18 – 24 kPa and φ = 42 – 50°), with samples behaving in a brittle fashion. Moisture content was artificially increased to 16% within the buried topsoil, which reduced the shear strength (c = 10 kPa, φ = 18°) and allowed it to behave plastically. Observational information indicating stability at Quarry Road included: shallow, discontinuous, cracks that do not display vertical offset; no scarp features or compressional zones typical of landsliding; no tilted or deformed structures; no movement in inclinometers; no basal shear zone identified in logged core to 20 m depth; low field moisture contents; no groundwater table; and high soil strength using Scala penetrometers. Limit equilibrium analysis of the slope was conducted using Rocscience software Slide 5.0 to verify the slope stability identified by observational methods. Friction, cohesion, and density values determined during laboratory were input into the two slope models investigated. Results gave minimum static factor of safety values for translational (along buried topsoil) and rotational (in the fill) slides of 2.4 – 4.2. Sensitivity of the slope to reduced shear strength parameters was analysed using c = 10 kPa and φ = 18° for the translational buried topsoil plane, and a cohesion of 0 kPa within the fill for the rotational plane. The only situation that gave a factor of safety <1.0 was in nonengineered fill at 0.5 m depth. Pseudostatic analysis based on previous peak ground acceleration (PGA) values for the Canterbury Earthquake Sequence, and predicted PGAs for future Alpine Fault and Hope Fault earthquakes established minimum factor of safety values between 1.2 and 3.3. Yield acceleration PGAs were computed to be between 0.8g and 1.6g. Based on all information gathered, the cracking at Quarry Road is considered to be shallow deformation in response to earthquake shaking, and not due to deep-seated landsliding. It is recommended that the currently bare site be managed by smoothing the land, installing contour drainage, and bioremediation of the surface soils to reduce surface water infiltration and runoff. Extensive earthworks, including removal of the fill, are considered unnecessary. Any future replacement of housing would be subject to site-specific investigations, and careful foundation design based on those results.