The Canterbury earthquakes, which started with the 7.1 magnitude event on September 4, 2010, caused significant damage in the region. The September 4 earthquakes brought substantial damage to land, buildings, and infrastructure, while the 6.3 magnitude earthquake on February 22, 2011 (and its subsequent aftershocks), brought even greater property damage, but also significant loss of life in addition to the region. Thousands were injured, and 185 persons died. A national State of Emergency was declared and remained in effect until April 30, 2011. A significant number of people required immediate assistance and support to deal with loss, injury, trauma experiences, and property damages. Many had to find alternate accommodation as their houses were too damaged to stay in. Of those affected, many were already vulnerable, and others had been too traumatized by the events to effectively deal with the challenges they were faced with. A number of human service organizations in the region, from both government and non-government sectors, joined forces to be able to more effectively and efficiently help those in need. This was the start of what would become known as the Earthquake Support Coordination Service. The aim of this report is to present an evaluation of the Earthquake Support Coordination Service and its collaborative organization, based on documentation and interviews with key stakeholders of the service. The aim is also to evaluate the service based on perspectives gathered among the clients as well as the coordinators working in the service. The final aim is to offer a reflection on the service model, and on what factors enabled the service, as well as recommendations regarding aspects of the service which may require review, and aspects which may be useful in other contexts.
Whole document is available to authenticated members of The University of Auckland until Feb. 2014 The increasing scale of losses from earthquake disasters has reinforced the need for property owners to become proactive in seismic risk reduction programs. However, despite advancement in seismic design methods and legislative frameworks, building owners are often reluctant to adopt mitigation measures required to reduce earthquake losses. The magnitude of building collapses from the recent Christchurch earthquakes in New Zealand shows that owners of earthquake prone buildings (EPBs) are not adopting appropriate risk mitigation measures in their buildings. Owners of EPBs are found unwilling or lack motivation to adopt adequate mitigation measures that will reduce their vulnerability to seismic risks. This research investigates how to increase the likelihood of building owners undertaking appropriate mitigation actions that will reduce their vulnerability to earthquake disaster. A sequential two-phase mixed methods approach was adopted for the research investigation. Multiple case studies approach was adopted in the first qualitative phase, followed by the second quantitative research phase that includes the development and testing of a framework. The research findings reveal four categories of critical obstacles to building owners‘ decision to adopt earthquake loss prevention measures. These obstacles include perception, sociological, economic and institutional impediments. Intrinsic and extrinsic interventions are proposed as incentives for overcoming these barriers. The intrinsic motivators include using information communication networks such as mass media, policy entrepreneurs and community engagement in risk mitigation. Extrinsic motivators comprise the use of four groups of incentives namely; financial, regulatory, technological and property market incentives. These intrinsic and extrinsic interventions are essential for enhancing property owners‘ decisions to voluntarily adopt appropriate earthquake mitigation measures. The study concludes by providing specific recommendations that earthquake risk mitigation managers, city councils and stakeholders involved in risk mitigation in New Zealand and other seismic risk vulnerable countries could consider in earthquake risk management. Local authorities could adopt the framework developed in this study to demonstrate a combination of incentives and motivators that yield best-valued outcomes. Consequently, actions can be more specific and outcomes more effective. The implementation of these recommendations could offer greater reasons for the stakeholders and public to invest in building New Zealand‘s built environment resilience to earthquake disasters
We examined the stratigraphy of alluvial fans formed at the steep range front of the Southern Alps at Te Taho, on the north bank of the Whataroa River in central West Coast, South Island, New Zealand. The range front coincides with the Alpine Fault, an Australian-Pacific plate boundary fault, which produces regular earthquakes. Our study of range front fans revealed aggradation at 100- to 300-year intervals. Radiocarbon ages and soil residence times (SRTs) estimated by a quantitative profile development index allowed us to elucidate the characteristics of four episodes of aggradation since 1000 CE. We postulate a repeating mode of fan behaviour (fan response cycle [FRC]) linked to earthquake cycles via earthquake-triggered landslides. FRCs are characterised by short response time (aggradation followed by incision) and a long phase when channels are entrenched and fan surfaces are stable (persistence time). Currently, the Te Taho and Whataroa River fans are in the latter phase. The four episodes of fan building we determined from an OxCal sequence model correlate to Alpine Fault earthquakes (or other subsidiary events) and support prior landscape evolution studies indicating ≥M7.5 earthquakes as the main driver of episodic sedimentation. Our findings are consistent with other historic non-earthquake events on the West Coast but indicate faster responses than other earthquake sites in New Zealand and elsewhere where rainfall and stream gradients (the basis for stream power) are lower. Judging from the thickness of fan deposits and the short response times, we conclude that pastoral farming (current land-use) on the fans and probably across much of the Whataroa River fan would be impossible for several decades after a major earthquake. The sustainability of regional tourism and agriculture is at risk, more so because of the vulnerability of the single through road in the region (State Highway 6).
The September and February earthquakes were terrifying and devastating. In February, 185 people were killed (this number excludes post earthquake related deaths) and several thousand injured. Damage to infrastructure above and below ground in and around Christchurch was widespread and it will take many years and billions of dollars to rebuild. The ongoing effects of the big quakes and aftershocks are numerous, with the deepest impact being on those who lost family and friends, their livelihoods and homes. What did Cantabrians do during the days, weeks and months of uncertainty and how have we responded? Many grieved, some left, some stayed, some arrived, many shovelled (liquefaction left thousands of tons of silt to be removed from homes and streets), and some used their expertise or knowledge to help in the recovery. This book highlights just some of the projects staff and students from The Faculty of Environment, Society and Design have been involved in from September 2010 to October 2012. The work is ongoing and the plan is to publish another book to document progress and new projects.
The housing and mortgage market in Christchurch experienced significant changes since the 2011 earthquake, especially after the reconstruction of the city. The increasing speed of Christchurch average house price exceed the average house price of the whole country, as well as the number of new dwellings. By this regard, this study surveyed the households in Christchurch to analyze the effect of the earthquake on housing and mortgage market. This includes factors such as housing price, interest rate, government policy and socioeconomic factors in terms of age, gender, educational attainment, income, marital status and family life cycle. Logistic regression model is used to analyze the data. The study provides an overview of the housing market and mortgage market in Christchurch. The logistic regression, results show changes on sensitivity between the socio-economic factors and house purchase, as well as mortgage borrowing pre- and post-earthquake. The result indicates that the earthquake in Christchurch has affected households’ decision on house purchase and mortgage borrowing.
This thesis investigates life-safety risk in earthquakes. The first component of the thesis utilises a dataset of earthquake injuries and deaths from recent earthquakes in New Zealand to identify cause, context, and risk factors of injury and death in the 2011 MW6.3 Christchurch earthquake and 2016 MW7.8 Kaikōura earthquake. Results show that nearly all deaths occurred from being hit by structural elements from buildings, while most injuries were caused by falls, strains and being hit by contents or non-structural elements. Statistical analysis of injured cases compared to an uninjured control group found that age, gender, building damage, shaking intensity, and behaviour during shaking were the most significant risk factors for injury during these earthquakes. The second part of the thesis uses the empirical findings from the first section to develop two tools for managing life-safety risk in earthquakes. The first tool is a casualty estimation model for health system and emergency response planning. An existing casualty model used in New Zealand was validated against observed data from the 2011 Christchurch earthquake and found to underestimate moderate and severe injuries by an order of magnitude. The model was then updated to include human behaviour such as protective actions, falls and strain type injuries that are dependent on shaking intensity, as well as injuries and deaths outside buildings. These improvements resulted in a closer fit to observed casualties for the 2011 Christchurch earthquake. The second tool that was developed is a framework to set seismic loading standards for design based on fatality risk targets. The proposed framework extends the risk-targeted hazard method, by moving beyond collapse risk targets, to fatality risk targets for individuals in buildings and societal risk in cities. The framework also includes treatment of epistemic uncertainty in seismic hazard to allow this uncertainty to be used in risk-based decision making. The framework is demonstrated by showing how the current New Zealand loading standards could be revised to achieve uniform life-safety risk across the country and how the introduction of a new loading factor can reduce risk aggregation in cities Not on Alma, moved and emailed. 1/02/2023 ce
The Canterbury earthquakes of 2010 and 2011 caused significant damage and disruption to the city of Christchurch, New Zealand. A Royal Commission was established to report on the causes of building failure as a result of the earthquakes as well as look at the legal and best-practice requirements for buildings in New Zealand Central Business Districts. The Royal Commission made 189 recommendations on a variety of matters including managing damaged buildings after an earthquake, the adequacy of building codes and standards, and the processes of seismic assessments of existing buildings to determine their earthquake vulnerability. In response the Ministry of Business, Innovation and Employment, the agency responsible for administering building regulation in New Zealand, established a work programme to assist with the Canterbury rebuild and to implement the lessons learned throughout New Zealand. The five primary work streams in the programme are: • Facilitating the Canterbury Rebuild • Structural Performance and Design Standards • Geotechnical and structural guidance • Existing Building Resilience • Post Disaster Building Management This paper provides more detail on each of the work streams. There has been significant collaboration between the New Zealand Government and the research community, technical societies, and engineering consultants, both within New Zealand and internationally, to deliver the programme and improve the resilience of the New Zealand built environment. This has presented major challenges for an extremely busy industry in the aftermath of the Canterbury earthquakes. The paper identifies the items of work that have been completed and the work that is still in progress at the time of writing.
Major earthquakes, such as the Canterbury and Kaikoura events recorded in New Zealand in 2010 and 2016 respectively, highlighted that floor systems can be heavily damaged. At a reduced or full scale, quasi-static experimental tests on structural sub-assemblies can help to establish the seismic performance of structural systems. However, the experimental performance obtained with such tests is likely to be dependent on the drift protocol adopted. This paper provides an overview of the drift protocols which have been assumed in previous relevant experimental activities, with emphasis on those adopted for testing floor systems. The paper also describes the procedure used to define the loading protocol applied in the testing of a large precast concrete floor diaphragm as part of the Recast floor project at the University of Canterbury. Finally, major limits of current loading protocols, and areas of future research, are identified.
Tens of thousands of landslides were generated over 10, 000 km2 of North Canterbury and Marlborough as a consequence of the 14 November 2016, MW7.8 Kaikōura Earthquake. The most intense landslide damage was concentrated in 3500 km2 around the areas of fault rupture. Given the sparsely populated area affected by landslides, only a few homes were impacted and there were no recorded deaths due to landslides. Landslides caused major disruption with all road and rail links with Kaikōura being severed. The landslides affecting State Highway 1 (the main road link in the South Island of New Zealand) and the South Island main trunk railway extended from Ward in Marlborough all the way to the south of Oaro in North Canterbury. The majority of landslides occurred in two geological and geotechnically distinct materials reflective of the dominant rock types in the affected area. In the Neogene sedimentary rocks (sandstones, limestones and siltstones) of the Hurunui District, North Canterbury and around Cape Campbell in Marlborough, first-time and reactivated rock-slides and rock-block slides were the dominant landslide type. These rocks also tend to have rock material strength values in the range of 5-20 MPa. In the Torlesse 'basement' rocks (greywacke sandstones and argillite) of the Kaikōura Ranges, first-time rock and debris avalanches were the dominant landslide type. These rocks tend to have material strength values in the range of 20-50 MPa. A feature of this earthquake is the large number (more than 200) of valley blocking landslides it generated. This was partly due to the steep and confined slopes in the area and the widely distributed strong ground shaking. The largest landslide dam has an approximate volume of 12(±2) M m3 and the debris from this travelled about 2.7 km2 downslope where it formed a dam blocking the Hapuku River. The long-term stability of cracked slopes and landslide dams from future strong earthquakes and large rainstorms are an ongoing concern to central and local government agencies responsible for rebuilding homes and infrastructure. A particular concern is the potential for debris floods to affect downstream assets and infrastructure should some of the landslide dams breach catastrophically. At least twenty-one faults ruptured to the ground surface or sea floor, with these surface ruptures extending from the Emu Plain in North Canterbury to offshore of Cape Campbell in Marlborough. The mapped landslide distribution reflects the complexity of the earthquake rupture. Landslides are distributed across a broad area of intense ground shaking reflective of the elongate area affected by fault rupture, and are not clustered around the earthquake epicentre. The largest landslides triggered by the earthquake are located either on or adjacent to faults that ruptured to the ground surface. Surface faults may provide a plane of weakness or hydrological discontinuity and adversely oriented surface faults may be indicative of the location of future large landslides. Their location appears to have a strong structural geological control. Initial results from our landslide investigations suggest predictive models relying only on ground-shaking estimates underestimate the number and size of the largest landslides that occurred.
Pumice materials, which are problematic from an engineering viewpoint, are widespread in the central part of the North Island. Considering the impacts of the 2010-2011 Christchurch earthquakes, a clear understanding of their properties under earthquake loading is necessary. For example, the 1987 Edgecumbe earthquake showed evidence of localised liquefaction of sands of volcanic origin. To elucidate on this, research was undertaken to investigate whether existing empirical field-based methods to evaluate the liquefaction potential of sands, which were originally developed for hard-grained soils, are applicable to crushable pumice-rich deposits. For this purpose, two sites, one in Whakatane and another in Edgecumbe, were selected where the occurrence of liquefaction was reported following the Edgecumbe earthquake. Manifestations of soil liquefaction, such as sand boils and ejected materials, have been reported at both sites. Field tests, including cone penetration tests (CPT), shear-wave velocity profiling, and screw driving sounding (SDS) tests were performed at the sites. Then, considering estimated peak ground accelerations (PGAs) at the sites based on recorded motions and possible range of ground water table locations, liquefaction analysis was conducted at the sites using available empirical approaches. To clarify the results of the analysis, undisturbed soil samples were obtained at both sites to investigate the laboratory-derived cyclic resistance ratios and to compare with the field-estimated values. Research results clearly showed that these pumice-rich soils do not fit existing liquefaction assessment frameworks and alternate methods are necessary to characterise them.
The Canterbury earthquake sequence in New Zealand’s South Island induced widespread liquefaction phenomena across the Christchurch urban area on four occasions (4 Sept 2010; 22 Feb; 13 June; 23 Dec 2011), that resulted in widespread ejection of silt and fine sand. This impacted transport networks as well as infiltrated and contaminated the damaged storm water system, making rapid clean-up an immediate post-earthquake priority. In some places the ejecta was contaminated by raw sewage and was readily remobilised in dry windy conditions, creating a long-term health risk to the population. Thousands of residential properties were inundated with liquefaction ejecta, however residents typically lacked the capacity (time or resources) to clean-up without external assistance. The liquefaction silt clean-up response was co-ordinated by the Christchurch City Council and executed by a network of contractors and volunteer groups, including the ‘Farmy-Army’ and the ‘Student-Army’. The duration of clean-up time of residential properties and the road network was approximately 2 months for each of the 3 main liquefaction inducing earthquakes; despite each event producing different volumes of ejecta. Preliminary cost estimates indicate total clean-up costs will be over NZ$25 million. Over 500,000 tonnes of ejecta has been stockpiled at Burwood landfill since the beginning of the Canterbury earthquakes sequence. The liquefaction clean-up experience in Christchurch following the 2010-2011 earthquake sequence has emerged as a valuable case study to support further analysis and research on the coordination, management and costs of large volume deposition of fine grained sediment in urban areas.
By closely examining the performance of a 22-storey steel framed building in Christchurch subject to various earthquakes over the past seven years, it is shown that a number of lessons can be learnt regarding the cost-effective consideration of non-structural elements. The first point in this work is that non-structural elements significantly affected the costs associated with repairing steel eccentrically braced frame (EBF) links. The decommissioning or rerouting of non-structural elements in the vicinity of damaged links in the case study building attributed to approximately half the total cost of their repair. Such costs could be significantly reduced if the original positioning of non-structural elements took account of the potential need to repair the EBF links. The second point highlighted is the role that pre-cast cladding apparently played on the distribution and type of damage in the building. Loss estimates obtained following the FEMA P-58 framework vary considerably when cladding is or isnt modelled, both because of changes to drift demands up the height of the building and because certain types of subsequent damage are likely to be cheaper to repair than others. Finally, costly repairs to non-structural partition walls were required not only after the moment magnitude 7.1 earthquake in 2010 but also in multiple aftershocks in the years that followed. Repair costs associated with aftershock events exceeded those from the main event, emphasizing the need to consider aftershocks within modern performance-based earthquake engineering and also the opportunity that exists to make more cost-effective repair strategies following damaging earthquakes.
Implementing seismic risk mitigation is a major challenge in many earthquake prone regions. The objective of this research is to investigate how property investment market practices can be used to enhance building owners’ decisions to improve seismic performance of earthquake prone buildings (EPBs). A case study method adopted, revealed the impacts of the property market stakeholders’ practices on seismic retrofit decisions. The findings from this research provide significant new insights on how property market-based incentives such as such as mandatory disclosure of seismic risks in all transactions in the property market, effective awareness seismic risk program and a unified earthquake safety assessment information system, can be used to enhance EPBs owners seismic retrofit decisions. These market-based incentives offer compelling reasons for the different property market stakeholders and the public at large to retain, care, invest, and act responsibly to rehabilitate EPBs. The findings suggest need for stakeholders involved in property investment and retrofit decisions to work together to foster seismic rehabilitation of EPBs.
Earthquakes rupture not only the objective realm of the physical landscape, but also the subjective landscape of emotions. Using the concepts of topophilia and topophobia developed by Yi-Fu Tuan as theories of love and fear of place, this paper investigates the impact of Christchurch’s earthquakes of 2010 and 2011 on relationships with the city’s landscape. Published accounts of the earthquakes in newspapers from around New Zealand are examined for evidence of how people responded to the situation, in particular their shifting relationship with familiar landscapes. The reports illustrate how residents and visitors reacted to the actual and perceived changes to their surroundings, grappling with how a familiar place had become alien and often startling. The extreme nature of the event and the death toll of 185 heightened perceptions of the landscape, and even the most taken-for-granted elements of the landscape became amplified in significance. Enhanced understanding of the landscape of emotions is a vital component of wellbeing. Through recognising that the impact of disasters and perceived threats to familiar places has a profound emotional effect, the significance of sense of place to wellbeing can be appreciated.
This article presents a subset of findings from a larger mixed methods CEISMIC1 funded study of twenty teachers’ earthquake experiences and post-earthquake adjustment eighteen months after a fatal earthquake struck Christchurch New Zealand, in the middle of a school day (Geonet Science, 2011; O’Toole & Friesen, 2016). This earthquake was a significant national and personal disaster with teachers’ emotional self-management as first responders being crucial to the students’ immediate safety (O’Toole & Friesen, 2016). At the beginning of their semi-structured interviews conducted eighteen months later, the teachers shared their earthquake stories (O’Toole & Friesen, 2016). They recalled the moment it struck in vivid detail, describing their experiences in terms of what they saw (destruction), heard (sonic boom, screaming children) and felt (fright and fear) as though they were back in that moment similar to flashbulb memory (Brown & Kulik, 1977). Their memories of the early aftermath were similarly vivid (Rubin & Kozin, 1984). This article focuses on how the mood meter (Brackett & Kremenitzer, 2011) was then used (with permission) to further explore the teachers’ perceived affect to enlighten their lived experiences.
This paper provides a brief discussion of observed strong ground motions from the 14 November 2016 Mw7.8 Kaikoura earthquake. Specific attention is given to examining observations in the near-source region where several ground motions exceeding 1.0g horizontal are recorded, as well as up to 2.7g in the vertical direction at one location. Ground motion response spectra in the near-source, North Canterbury, Marlborough and Wellington regions are also examined and compared with design levels. Observed spectral amplitudes are also compared with predictions from empirical and physics-based ground motion modelling.
This paper presents on-going challenges in the present paradigm shift of earthquakeinduced ground motion prediction from empirical to physics-based simulation methods. The 2010-2011 Canterbury and 2016 Kaikoura earthquakes are used to illustrate the predictive potential of the different methods. On-going efforts on simulation validation and theoretical developments are then presented, as well as the demands associated with the need for explicit consideration of modelling uncertainties. Finally, discussion is also given to the tools and databases needed for the efficient utilization of simulated ground motions both in specific engineering projects as well as for near-real-time impact assessment.
We measure the longer-term effect of a major earthquake on the local economy, using night-time light intensity measured from space, and investigate whether insurance claim payments for damaged residential property affected the local recovery process. We focus on the destructive Christchurch earthquake of 2011 as our case study. In this event more than 95% of residential housing units were covered by insurance, but insurance payments were staggered over 5 years, enabling us to identify their local impact. We find that night-time luminosity can capture the process of recovery and describe the recovery’s determinants. We also find that insurance payments contributed significantly to the process of economic recovery after the earthquake, but delayed payments were less affective and cash settlement of claims were more affective in contributing to local recovery than insurance-managed rebuilding.
This study explores the role and value of urban community gardens following a major crisis: the 2010/11 earthquakes in Christchurch, New Zealand.
©2019. American Geophysical Union. All Rights Reserved. Earthquakes have been inferred to induce hydrological changes in aquifers on the basis of either changes to well water-levels or tidal behavior, but the relationship between these changes remains unclear. Here, changes in tidal behavior and water-levels are quantified using a hydrological network monitoring gravel aquifers in Canterbury, New Zealand, in response to nine earthquakes (of magnitudes M w 5.4 to 7.8) that occurred between 2008 and 2015. Of the 161 wells analyzed, only 35 contain water-level fluctuations associated with “Earth + Ocean” (7) or “Ocean” (28) tides. Permeability reduction manifest as changes in tidal behavior and increased water-levels in the near field of the Canterbury earthquake sequence of 2010–2011 support the hypothesis of shear-induced consolidation. However, tidal behavior and water-level changes rarely occurred simultaneously (~2%). Water-level changes that occurred with no change in tidal behavior reequilibrated at a new postseismic level more quickly (on timescales of ~50 min) than when a change in tidal behavior occurred (~240 min to 10 days). Water-level changes were more than likely to occur above a peak dynamic stress of ~50 kPa and were more than likely to not occur below ~10 kPa. The minimum peak dynamic stress required for a tidal behavior change to occur was ~0.2 to 100 kPa.
Earthquakes and other major disasters present communities and their authorities with an extraordinary challenge. While a lot can be done to prepare a city’s response in the event of a disaster, few cities are truly prepared for the initial impact, devastation, grief, and the seemingly formidable challenge of recovery. Many people find themselves overwhelmed with facing critical problems; ones which they have often never had experience with before. While the simple part is agreeing on a desired outcome for recovery, it appears the argument that exists between stakeholders is the conflicting ideas of How To effectively achieve the main objective. What I have identified as an important step toward collaborating on the How To of recovery is to identify the ways in which each discipline can most effectively contribute to the recovery. Landscape architecture is just one of the many disciplines (that should be) invovled in the How To of earthquake recovery. Canterbury has an incredible opportunity to set the benchmark for good practice in earthquake recovery. To make the most of this opportuntiy, it is critical that landscape architects are more effectively engaged in roles of recovery across a much broader spectrum of recovery activities. The overarching purpose of this research is to explore and provide insight to the current and potential of landscape architects in the earthquake recovery period in Canterbury, using international good practice as a benchmark. The research is aimed at stimulating and guiding landscape architects dealing with the earthquake recovery in Canterbury, while informing stakeholders: emergency managers, authorities, other disciplines and the wider community of themost effective role(s) for landscape architects in the recovery period.
This report forms part of a research project examining rural community resilience to natural hazard events, with a particular focus on transient population groups. A preliminary desktop and scoping exercise was undertaken to examine nine communities affected by the Kaikoura earthquake and to identify the variety of transient population groups that are commonly (and increasingly) found in rural New Zealand (see Wilson & Simmons, 2017). From this, four case study communities – Blenheim, Kaikoura, Waiau and St Arnaud – were selected to represent a range of settlement types. These communities varied in respect of social, economic and geographic features, including the presence of particular transient population groups, and earthquake impact. While the 2016 Kaikoura earthquake provided a natural hazard event on which to focus the research, the research interest was in long-term (and broad) community resilience, rather than short-term (and specific) response and recovery actions which occurred post-earthquake.
The 2010 and 2011 earthquakes have had a devastating impact on the city of Christchurch, New Zealand. The level of destruction has been especially evident in the central business district where it has been estimated over 1000 buildings have already been or will eventually require demolition. Although, contrary to expectations, most of the fatalities were in relatively modern buildings, the Victorian and Edwardian era building stock was especially hard hit in terms of property damage. Unfortunately this era and style of building were also the focus of the most successful inner city revitalisation projects to date. A major research project is now underway examining the impact on the earthquakes on one of these revitalisation areas. The first step is to examine the international literature on similar inner city revitalisation or gentrification areas and in particular the characteristics of owners and occupiers attracted to this type of environment. This is the focus of this paper.
Following the September 2010 earthquake and the closure of a number of campus libraries, library staff at the University of Canterbury was forced to rethink how they connected with their users. The established virtual reference service now meant library staff could be contacted regardless of their physical location. After the February earthquake, with University library closures ranging from 3 weeks to indefinite, this service came into its own as a vital communication tool. It facilitated contact between the library and both students and academics, as well as proving invaluable as a means for library staff to locate and communicate with each other. Transcripts from our post-earthquake interactions with users were analyzed using NVivo and will be presented in poster format showing the increase in usage of the service following the earthquakes, who used the service most, and the numbers and types of questions received. Our virtual reference tool was well used in the difficult post-earthquake periods and we can see this usage continuing as university life returns to normal.
Landslides are significant hazards, especially in seismically-active mountainous regions, where shaking amplified by steep topography can result in widespread landsliding. These landslides present not only an acute hazard, but a chronic hazard that can last years-to-decades after the initial earthquake, causing recurring impacts. The Mw 7.8 Kaikōura earthquake caused more than 20,000 landslides throughout North Canterbury and resulted in significant damage to nationally significant infrastructure in the coastal transport corridor (CTC), isolating Kaikōura from the rest of New Zealand. In the years following, ongoing landsliding triggered by intense rainfall exacerbated the impacts and slowed the recovery process. However, while there is significant research on co-seismic landslides and their initial impacts in New Zealand, little research has explored the evolution of co-seismic landslides and how this hazard changes over time. This research maps landslides annually between 2013 and 2021 to evaluate the changes in pre-earthquake, co-seismic and post-earthquake rates of landsliding to determine how landslide hazard has changed over this time. In particular, the research explores how the number, area, and spatial distribution of landslides has changed since the earthquake, and whether post-earthquake mitigation works have in any way affected the long-term landslide hazard. Mapping of landslides was undertaken using open-source, medium resolution Landsat-8 and Sentinel-2 satellite imagery, with landslides identified visually and mapped as single polygons that capture both the source zone and deposit. Three study areas with differing levels of post-earthquake mitigation are compared: (i) the northern CTC, where the majority of mitigation was in the form of active debris removal; (ii) the southern CTC, where mitigation was primarily via passive protection measures; and (iii) Mount Fyffe, which has had no mitigation works since the earthquake. The results show that despite similar initial impacts during the earthquake, the rate of recovery in terms of landslide rates varies substantially across the three study areas. In Mount Fyffe, the number and area of landslides could take 45 and 22 years from 2021 respectively to return to pre-earthquake levels at the current rate. Comparatively, in the CTC, it could take just 5 years and 3-4 years from 2021 respectively. Notably, the fastest recovery in terms of landslide rates in the CTC was primarily located directly along the transport network, whereas what little recovery did occur in Mount Fyffe appeared to follow no particular pattern. Importantly, recovery rates in the northern CTC were notably higher than in the southern CTC, despite greater co-seismic impacts in the former. Combined, these results suggest the active, debris removal mitigation undertaken in the northern CTC may have had the effect of dramatically reducing the time for landslide rates to return to pre-earthquake levels. The role of slope angle and slope aspect were explored to evaluate if these observations could be driven by local differences in topography. The Mount Fyffe study area has higher slope angles than the CTC as a whole and landslides predominantly occurred on slightly steeper slopes than in the CTC. This may have contributed to the longer recovery times for landsliding in Mount Fyffe due to greater gravitational instability, however the observed variations are minor compared to the differences in recovery rates. In terms of slope aspect, landslides in Mount Fyffe preferentially occurred on north- and south-facing slopes whereas landslides in the CTC preferred the east- and south-facing slopes. The potential role of these differences in landslide recovery remains unclear but may be related to the propagation direction of the earthquake and the tracking direction of post-earthquake ex-tropical cyclones. Finally, landslides in the CTC are observed to be moving further away from the transport network and the number of landslides impacting the CTC decreased significantly since the earthquake. Nevertheless, the potential for further landslide reactivation remains. Therefore, despite the recovery in the CTC, it is clear that there is still risk of the transport network being impacted by further landsliding, at least for the next 3-5 yrs.
Rapid, reliable information on earthquake-affected structures' current damage/health conditions and predicting what would happen to these structures under future seismic events play a vital role in accelerating post-event evaluations, leading to optimized on-time decisions. Such rapid and informative post-event evaluations are crucial for earthquake-prone areas, where each earthquake can potentially trigger a series of significant aftershocks, endangering the community's health and wealth by further damaging the already-affected structures. Such reliable post-earthquake evaluations can provide information to decide whether an affected structure is safe to stay in operation, thus saving many lives. Furthermore, they can lead to more optimal recovery plans, thus saving costs and time. The inherent deficiency of visual-based post-earthquake evaluations and the importance of structural health monitoring (SHM) methods and SHM instrumentation have been highlighted within this thesis, using two earthquake-affected structures in New Zealand: 1) the Canterbury Television (CTV) building, Christchurch; 2) the Bank of New Zealand (BNZ) building, Wellington. For the first time, this thesis verifies the theoretically- and experimentally validated hysteresis loop analysis (HLA) SHM method for the real-world instrumented structure of the BNZ building, which was damaged severely due to three earthquakes. Results indicate the HLA-SHM method can accurately estimate elastic stiffness degradation for this reinforced concrete (RC) pinched structure across the three earthquakes, which remained unseen until after the third seismic event. Furthermore, the HLA results help investigate the pinching effects on the BNZ building's seismic response. This thesis introduces a novel digital clone modelling method based on the robust and accurate SHM results delivered by the HLA method for physical parameters of the monitored structure and basis functions predicting the changes of these physical parameters due to future earthquake excitations. Contrary to artificial intelligence (AI) based predictive methods with black-box designs, the proposed predictive method is entirely mechanics-based with an explicitly-understandable design, making them more trusted and explicable to stakeholders engaging in post-earthquake evaluations, such as building owners and insurance firms. The proposed digital clone modelling framework is validated using the BNZ building and an experimental RC test structure damaged severely due to three successive shake-table excitations. In both structures, structural damage intensifies the pinching effects in hysteresis responses. Results show the basis functions identified from the HLA-SHM results for both structures under Event 1 can online estimate structural damage due to subsequent Events 2-3 from the measured structural responses, making them valuable tool for rapid warning systems. Moreover, the digital twins derived for these two structures under Event 1 can successfully predict structural responses and damage under Events 2-3, which can be integrated with the incremental dynamic analysis (IDA) method to assess structural collapse and its financial risks. Furthermore, it enables multi-step IDA to evaluate earthquake series' impacts on structures. Overall, this thesis develops an efficient method for providing reliable information on earthquake-affected structures' current and future status during or immediately after an earthquake, considerably guaranteeing safety. Significant validation is implemented against both experimental and real data of RC structures, which thus clearly indicate the accurate predictive performance of this HLA-based method.
Natural disasters are increasingly disruptive events that affect livelihoods, organisations, and economies worldwide. Research has identified the impacts and responses of organisations to different types of natural disasters, and have outlined factors, such as industry sector, that are important to organisational vulnerability and resilience. One of the most costly types of natural disasters in recent years has been earthquakes, and yet to date, the majority of studies have focussed on the effects of earthquakes in urban areas, while rural organisational impact studies have primarily focused on the effects of meteorological and climatic driven hazards. As a result, the likely impacts of an earthquake on rural organisations in a developed context is unconstrained in the literature. In countries like New Zealand, which have major earthquakes and agricultural sectors that are significant contributors to the economy, it is important to know what impacts an earthquake event would have on the rural industries, and how these impacts compare to that of a more commonly analysed, high-frequency event. In September of 2010, rural organisations in Canterbury experienced the 4 September 2010 Mw 7.1 `Darfield' earthquake and the associated aftershocks, which came to be known as the Canterbury earth- quake sequence. The earthquake sequence caused intense ground shaking, creating widespread critical service outages, structural and non-structural damage to built infrastructure, as well as ground surface damage from ooding, liquefaction and surface rupture. Concurrently on September 18 2010, rural organisations in Southland experienced an unseasonably late snowstorm and cold weather snap that brought prolonged sub-zero temperatures, high winds and freezing rain, damaging structures in the City of Invercargill and causing widespread livestock losses and production decreases across the region. This thesis documents the effects of the Canterbury earthquake sequence and Southland snowstorm on farming and rural non-farming organisations, utilizing comparable methodologies to analyse rural organisational impacts, responses and recovery strategies to natural disasters. From the results, a short- term impact assessment methodology is developed for multiple disasters. Additionally, a regional asset repair cost estimation model is proposed for farming organisations following a major earthquake event, and the use of social capital in rural organisational recovery strategies following natural disasters is analysed.
Throughout 2010 and 2011, the city of Christchurch, New Zealand, suffered a series of devastating earthquakes that caused serious damage to the city. This study examines the effect these earthquakes have had on the sport of swimming in Christchurch. It specifically focuses on three different aspects of the swimming industry: indoor competitive swimming, open water swimming and learning to swim. It reports on the industry prior to the earthquakes before examining the developments subsequent to the shakes. The effects on both facilities and participation numbers were examined. Results showed that many indoor swimming facilities were lost which had significant flow-on effects. In addition, many beaches were out of bounds and almost half of the schools in Canterbury lost the use of their own swimming pools. In terms of participation numbers, results showed that while there was a decrease in the number of indoor competitive swimmers, Canterbury clubs were still highly competitive and their rankings at events either remained similar or bettered during and after the period of the earthquakes. On the other hand, an increase in the number of participants was seen in swimming lessons as temporary pools were constructed and subsidies were offered to cover transport and lesson costs. Open water swimming, however, seems to have been relatively unaffected by the earthquakes.This report was made possible through Lincoln University’s Summer Scholarship programme. The authors would also like to acknowledge those anonymous interviewees who provided some valuable insight into the swimming industry in Christchurch.
In this paper, the characteristics of near-fault ground motions recorded during the Mw7.1 Darfield and Mw 6.2 Christchurch earthquakes are examined and compared with existing empirical models. The characteristics of forward-directivity effects are first examined using a wavelet-based pulse-classification algorithm. This is followed by an assessment of the adequacy of empirical models which aim to capture the effect of directivity effects on amplifying the acceleration response spectra; and the period and peak velocity of the forward-directivity pulse. It is illustrated that broadband directivity models developed by Somerville et al. (1997) and Abrahamson (2000) generally under-predict the observed amplification of response spectral ordinates at longer vibration periods. In contrast, a recently developed narrowband model by Shahi and Baker (2011) provides significantly improved predictions by amplifying the response spectra within a small range of periods surrounding the directivity pulse period. Although the empirical predictions of the pulse period are generally favourable for the Christchurch earthquake, the observations from the Darfield earthquake are significantly under-predicted. The elongation in observed pulse periods is inferred as being a result of the soft sedimentary soils of the Canterbury basin. However, empirical predictions of the observed peak velocity associated with the directivity pulse are generally adequate for both events.
