Strong ground motions observed in the 22 February 2011 Christchurch earthq…
Research papers, University of Canterbury Library
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At 4.35am on Saturday 4 September 2010, a magnitude 7.1 earthquake struck near the township of Darfield in Canterbury leading to widespread damage in Christchurch and the wider central Canterbury region. Though it was reported no lives were lost, that was not entirely correct. Over 3,000 animals perished as a result of the earthquake and 99% of these deaths would have been avoidable if appropriate mitigation measures had been in place. Deaths were predominantly due to zoological vulnerability of birds in captive production farms. Other problems included lack of provision of animal welfare at evacuation centres, issues associated with multiple lost and found pet services, evacuation failure due to pet separation and stress impact on dairy herds and associated milk production. The Canterbury Earthquake has highlighted concerns over a lack of animal emergency welfare planning and capacity in New Zealand, an issue that is being progressed by the National Animal Welfare Emergency Management Group. As animal emergency management becomes better understood by emergency management and veterinary professionals, it is more likely that both sectors will have greater demands placed upon them by national guidelines and community expectations to ensure provisions are made to afford protection of animals in times of disaster. A subsequent and more devastating earthquake struck the region on Monday 22 February 2011; this article however is primarily focused on the events pertaining to the September 4 event.
The 4th of September 2010 Mw 7.1 Darfield (Canterbury) earthquake had generated significant ground shaking within the Christchurch Central Business District (CBD). Despite the apparently significant shaking, the observed structural damage for pre-1970s reinforced concrete (RC) buildings was indeed limited and lower than what was expected for such typology of buildings. This paper explores analytically and qualitatively the different aspects of the "apparent‟ good seismic performance of the pre-1970s RC buildings in the Christchurch CBD, following the earthquake reconnaissance survey by the authors. Damage and building parameters survey result, based on a previously established inventory of building stock of these non-ductile RC buildings, is briefly reported. From an inventory of 75 buildings, one building was selected as a numerical case-study to correlate the observed damage with the non-linear analyses. The result shows that the pre-1970s RC frame buildings performed as expected given the intensity of the ground motion shaking during the Canterbury earthquake. Given the brittle nature of this type of structure, it was demonstrated that more significant structural damage and higher probability of collapse could occur when the buildings were subjected to alternative input signals with different frequency content and duration characteristics and still compatible to the seismicity hazard for Christchurch CBD.
Geomorphic, structural and chronological data are used to establish the late Quaternary paleoseismicity of the active dextral-oblique Northern Esk Fault in North Canterbury, New Zealand. Detailed field mapping of the preserved c. 35 km of surface traces between the Hurunui River and Ashley Head reveals variations in strike ranging from 005° to 057°. Along with kinematic data collected from fault plane striae and offset geomorphic markers along the length of the fault these variations are used to distinguish six structural subsections of the main trace, four dextral-reverse and two dextral-normal. Displacements of geomorphic markers such as minor streams and ridges are measured using differential GPS and rangefinder equipment to reveal lateral offsets ranging from 3.4 to 23.7 m and vertical offsets ranging from < 1 to 13.5 m. Characteristic single event displacements of c. 5 m and c. 2 m have been calculated for strike-slip and reverse sections respectively. The use of fault scaling relationships reveals an anomalously high displacement to surface rupture length ratio when compared to global data sets. Fault scaling relationships based on width limited ruptures and magnitude probabilities from point measurements of displacement imply earthquake magnitudes of Mw 7.0 to 7.5. Optically Stimulated Luminescence (OSL) ages from displaced Holocene alluvial terraces at the northern extent of the active trace along with OSL and radiocarbon samples of the central sections constrain the timing of the last two surface rupturing events (11.15 ±1.65 and 3.5 ± 2.8 ka) and suggest a recurrence interval of c. 5612 ± 445 years and late Quaternary reverse and dextral slip rates of c. 0.31 mm/yr and 0.82 mm/yr respectively. The results of this study show that the Northern Esk Fault accommodates an important component of the c. 0.7 – 2 mm/yr of unresolved strain across the plate boundary within the North Canterbury region and affirm the Esk Fault as a source of potentially damaging ground shaking in the Canterbury region.
An overview of the 22 February 2011 Christchurch earthquake is presented in the context of characterization of extreme/rare events. Focus is given to the earthquake source, observed near-source strong ground motions, and effects of site response, while structural response and consequences are mentioned for completeness. For each of the above topics comparisons and discussions are made with predictive models for each of phenomena considered. In light of the observations and predictive model comparisons, the author’s opinion on improving the characterization of such extreme/rare events, and their appropriate consideration in seismic design is presented
Disasters can create the equivalent of 20 years of waste in only a few days. Disaster waste can have direct impacts on public health and safety, and on the environment. The management of such waste has a great direct cost to society in terms of labor, equipment, processing, transport and disposal. Disaster waste management also has indirect costs, in the sense that slow management can slow down a recovery, greatly affecting the ability of commerce and industry to re-start. In addition, a disaster can lead to the disruption of normal solid waste management systems, or result in inappropriate management that leads to expensive environmental remediation. Finally, there are social impacts implicit in disaster waste management decisions because of psychological impact we expect when waste is not cleared quickly or is cleared too quickly. The paper gives an overview of the challenge of disaster waste management, examining issues of waste quantity and composition; waste treatment; environmental, economic, and social impacts; health and safety matters; and planning. Christchurch, New Zealand, and the broader region of Canterbury were impacted during this research by a series of shallow earthquakes. This has led to the largest natural disaster emergency in New Zealand’s history, and the management of approximately 8 million tons of building and infrastructure debris has become a major issue. The paper provides an overview of the status of disaster waste management in Christchurch as a case study. A key conclusion is the vital role of planning in effective disaster waste management. In spite of the frequency of disasters, in most countries the ratio of time spent on planning for disaster waste management to the time spent on normal waste management is extremely low. Disaster waste management also requires improved education or training of those involved in response efforts. All solid waste professionals have a role to play to respond to the challenges of disaster waste management.
The timeliness and quality of recovery activities are impacted by the organisation and human resourcing of the physical works. This research addresses the suitability of different resourcing strategies on post-disaster demolition and debris management programmes. This qualitative analysis primarily draws on five international case studies including 2010 Canterbury earthquake, 2009 L’Aquila earthquake, 2009 Samoan Tsunami, 2009 Victorian Bushfires and 2005 Hurricane Katrina. The implementation strategies are divided into two categories: collectively and individually facilitated works. The impacts of the implementation strategies chosen are assessed for all disaster waste management activities including demolition, waste collection, transportation, treatment and waste disposal. The impacts assessed include: timeliness, completeness of projects; and environmental, economic and social impacts. Generally, the case studies demonstrate that detritus waste removal and debris from major repair work is managed at an individual property level. Debris collection, demolition and disposal are generally and most effectively carried out as a collective activity. However, implementation strategies are affected by contextual factors (such as funding and legal constraints) and the nature of the disaster waste (degree of hazardous waste, geographical spread of waste etc.) and need to be designed accordingly. Community involvement in recovery activities such as demolition and debris removal is shown to contribute positively to psychosocial recovery.
Disaster recovery is significantly affected by funding availability. The timeliness and quality of recovery activities are not only impacted by the extent of the funding but also the mechanisms with which funding is prioritised, allocated and delivered. This research addresses the impact of funding mechanisms on the effectiveness and efficiency of post-disaster demolition and debris management programmes. A qualitative assessment of the impacts on recovery of different funding sources and mechanisms was carried out, using the 2010 Canterbury Earthquake as well as other recent international events as case studies. The impacts assessed include: timeliness, completeness, environmental, economic and social impacts. Of the case studies investigated, the Canterbury Earthquake was the only disaster response to rely solely on a privatised approach to insurance for debris management. Due to the low level of resident displacement and low level of hazard in the waste, this was a satisfactory approach, though not ideal. This approach has led to greater organisational complexity and delays. For many other events, the potential community wide impacts caused by the prolonged presence of disaster debris means that publicly funded and centrally facilitated programmes appear to be the most common and effective method of managing disaster waste.
A magnitude 6.3 earthquake struck the city of Christchurch at 12:51pm on Tuesday 22 February 2011. The earthquake caused 182 fatalities, a large number of injuries, and resulted in widespread damage to the built environment, including significant disruption to the lifelines. The event created the largest lifeline disruption in a New Zealand city in 80 years, with much of the damage resulting from extensive and severe liquefaction in the Christchurch urban area. The Christchurch earthquake occurred when the Canterbury region and its lifelines systems were at the early stage of recovering from the 4 September 2010 Darfield (Canterbury) magnitude 7.1 earthquake. This paper describes the impact of the Christchurch earthquake on lifelines by briefly summarising the physical damage to the networks, the system performance and the operational response during the emergency management and the recovery phase. Special focus is given to the performance and management of the gas, electric and road networks and to the liquefaction ejecta clean-up operations that contributed to the rapid reinstatement of the functionality of many of the lifelines. The water and wastewater system performances are also summarized. Elements of resilience that contributed to good network performance or to efficient emergency and recovery management are highlighted in the paper.
This paper describes pounding damage sustained by buildings and bridges in the February 2011 Christchurch earthquake. Approximately 6% of buildings in Christchurch CBD were observed to have suffered some form of serious pounding damage. Almost all of this pounding damage occurred in masonry buildings, further highlighting their vulnerability to this phenomenon. Modern buildings were found to be vulnerable to pounding damage where overly stiff and strong ‘flashing’ components were installed in existing building separations. Soil variability is identified as a key aspect that amplifies the relative movement of buildings, and hence increases the likelihood of pounding damage. Pounding damage in bridges was found to be relatively minor and infrequent in the Christchurch earthquake.
Blended learning plays an important role in many tertiary institutions but little has been written about the implementation of blended learning in times of adversity, natural disaster or crisis. This paper describes how, in the wake of the 22 February Canterbury earthquake, five teacher educators responded to crisis-driven changing demands and changing directions. Our narratives describe how blended learning provided students in initial teacher education programmes with some certainty and continuity during a time of civil emergency. The professional learning generated from our experiences provides valuable insights for designing and preparing for blended learning in times of crisis, as well as developing resilient blended learning programmes for the future.
Currently there is a worldwide renaissance in timber building design. At the University of Canterbury, new structural systems for commercial multistorey timber buildings have been under development since 2005. These systems incorporate large timber sections connected by high strength post-tensioning tendons, and timber-concrete composite floor systems, and aim to compete with existing structural systems in terms of cost, constructability, operational and seismic performance. The development of post-tensioned timber systems has created a need for improved lateral force design approaches for timber buildings. Current code provisions for seismic design are based on the strength of the structure, and do not adequately account for its deformation. Because timber buildings are often governed by deflection, rather than strength, this can lead to the exceedence of design displacement limitations imposed by New Zealand codes. Therefore, accurate modeling approaches which define both the strength and deformation of post-tensioned timber buildings are required. Furthermore, experimental testing is required to verify the accuracy of these models. This thesis focuses on the development and experimental verification of modeling approaches for the lateral force design of post-tensioned timber frame and wall buildings. The experimentation consisted of uni-direcitonal and bi-directional quasi-static earthquake simulation on a two-thirds scale, two-storey post-tensioned timber frame and wall building with timber-concrete composite floors. The building was subjected to lateral drifts of up to 3% and demonstrated excellent seismic performance, exhibiting little damage. The building was instrumented and analyzed, providing data for the calibration of analytical and numerical models. Analytical and numerical models were developed for frame, wall and floor systems that account for significant deformation components. The models predicted the strength of the structural systems for a given design performance level. The static responses predicted by the models were compared with both experimental data and finite element models to evaluate their accuracy. The frame, wall and floor models were then incorporated into an existing lateral force design procedure known as displacement-based design and used to design several frame and wall structural systems. Predictions of key engineering demand parameters, such as displacement, drift, interstorey shear, interstorey moment and floor accelerations, were compared with the results of dynamic time-history analysis. It was concluded that the numerical and analytical models, presented in this thesis, are a sound basis for determining the lateral response of post-tensioned timber buildings. However, future research is required to further verify and improve these prediction models.
This paper describes the performance of (or damage to) ceilings in buildings during the 22nd February 2011 Christchurch earthquake and the subsequent aftershocks. In buildings that suffered severe structural damage, ceilings and other non-structural components (rather expectedly) failed, but even in buildings with little damage to their structural systems, ceilings were found to be severely damaged. The extent of ceiling damage, where the ceilings were subject to severe shaking, depended on the type of the ceiling system, the size and weight of the ceilings and the interaction of ceilings with other elements. The varieties and extent of observed ceiling damage are discussed in this paper with the help of photographs taken after the earthquake.
The 22 February 2011, Mw6.2-6.3 Christchurch earthquake is the most costly earthquake to affect New Zealand, causing 181 fatalities and severely damaging thousands of residential and commercial buildings, and most of the city lifelines and infrastructure. This manuscript presents an overview of observed geotechnical aspects of this earthquake as well as some of the completed and on-going research investigations. A unique aspect, which is particularly emphasized, is the severity and spatial extent of liquefaction occurring in native soils. Overall, both the spatial extent and severity of liquefaction in the city was greater than in the preceding 4th September 2010 Darfield earthquake, including numerous areas that liquefied in both events. Liquefaction and lateral spreading, variable over both large and short spatial scales, affected commercial structures in the Central Business District (CBD) in a variety of ways including: total and differential settlements and tilting; punching settlements of structures with shallow foundations; differential movements of components of complex structures; and interaction of adjacent structures via common foundation soils. Liquefaction was most severe in residential areas located to the east of the CBD as a result of stronger ground shaking due to the proximity to the causative fault, a high water table approximately 1m from the surface, and soils with composition and states of high susceptibility and potential for liquefaction. Total and differential settlements, and lateral movements, due to liquefaction and lateral spreading is estimated to have severely compromised 15,000 residential structures, the majority of which otherwise sustained only minor to moderate damage directly due to inertial loading from ground shaking. Liquefaction also had a profound effect on lifelines and other infrastructure, particularly bridge structures, and underground services. Minor damage was also observed at flood stop banks to the north of the city, which were more severely impacted in the 4th September 2010 Darfield earthquake. Due to the large high-frequency ground motion in the Port hills numerous rock falls and landslides also occurred, resulting in several fatalities and rendering some residential areas uninhabitable.
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.
The NMIT Arts & Media Building is the first in a new generation of multistorey timber structures. It employs an advanced damage avoidance earthquake design that is a world first for a timber building. Aurecon structural engineers are the first to use this revolutionary Pres-Lam technology developed at the University of Canterbury. This technology marks a fundamental change in design philosophy. Conventional seismic design of multi-storey structures typically depends on member ductility and the acceptance of a certain amount of damage to beams, columns and walls. The NMIT seismic system relies on pairs of coupled LVL shear walls that incorporate high strength steel tendons post-tensioned through a central duct. The walls are centrally fixed allowing them to rock during a seismic event. A series of U-shaped steel plates placed between the walls form a coupling mechanism, and act as dissipators to absorb seismic energy. The design allows the primary structure to remain essentially undamaged while readily replaceable connections act as plastic fuses. In this era where sustainability is becoming a key focus, the extensive use of timber and engineered-wood products such as LVL make use of a natural resource all grown and manufactured within a 100km radius of Nelson. This project demonstrates that there are now cost effective, sustainable and innovative solutions for multi-story timber buildings with potential applications for building owners in seismic areas around the world.
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.
An extensive research program is on-going at the University of Canterbury, New Zealand to develop new technologies to permit the construction of multi-storey timber buildings in earthquake prone areas. The system combines engineered timber beams, columns and walls with ductile moment resisting connections using post-tensioned tendons and eventually energy dissipaters. The extensive experimental testing on post-tensioned timber building systems has proved a remarkable lateral response of the proposed solutions. A wide number of post-tensioned timber subassemblies, including beam-column connections, single or coupled walls and column-foundation connections, have been analysed in static or quasi-static tests. This contribution presents the results of the first dynamic tests carried out with a shake-table. Model frame buildings (3-storey and 5-storey) on one-quarter scale were tested on the shake-table to quantify the response of post-tensioned timber frames during real-time earthquake loading. Equivalent viscous damping values were computed for post-tensioned timber frames in order to properly predict their response using numerical models. The dynamic tests were then complemented with quasi-static push and pull tests performed to a 3-storey post-tensioned timber frame. Numerical models were included to compare empirical estimations versus dynamic and quasi-static experimental results. Different techniques to model the dynamic behaviour of post-tensioned timber frames were explored. A sensitivity analysis of alternative damping models and an examination of the influence of designer choices for the post-tensioning force and utilization of column armouring were made. The design procedure for post-tensioned timber frames was summarized and it was applied to two examples. Inter-storey drift, base shear and overturning moments were compared between numerical modelling and predicted/targeted design values.
This manuscript provides a critical examination of the ground motions recorded in the near-source region resulting from the 22 February 2011 Christchurch earthquake. Particular attention is given to reconciling the observed spatial distribution of ground motions in terms of physical phenomena related to source, path and site effects. The large number of near-source observed strong ground motions show clear evidence of: forward-directivity, basin generated surface waves, liquefaction and other significant nonlinear site response. The pseudo-acceleration response spectra (SA) amplitudes and significant duration of strong motions agree well with empirical prediction models, except at long vibration periods where the influence of basin-generated surface waves and nonlinear site response are significant and not adequately accounted for in empirical SA models. Pseudo-acceleration response spectra are also compared with those observed in the 4 September 2010 Darfield earthquake and routine design response spectra used in order to emphasise the amplitude of ground shaking and elucidate the importance of local geotechnical characteristics on surface ground motions. The characteristics of the observed vertical component accelerations are shown to be strongly dependent on source-to-site distance and are comparable with those from the 4 September 2010 Darfield earthquake, implying the large amplitudes observed are simply a result of many observations at close distances rather than a peculiar source effect.
Extended Direct Analysis (EDA), developed at the University of Canterbury, is an advance on the AISC Direct Analysis method for the analysis of frames subjected to static forces. EDA provides a faster, simple and more rational way to properly consider the second-order effects, initial residual stresses (IRS) and the initial imperfections or steel structures under one directional loading than conventional analysis methods. This research applied the EDA method to quantify the effect of member overstrength on frame behaviour for a single storey frame. Also, the effects of IRS, which were included in the EDA static analysis, but which are not considered explicitly in non-linear seismic analysis, were evaluated in two ways. Firstly, they were considered for simple structures subject to increasing cyclic displacement in different directions. Secondly, incremental dynamic analysis with realistic ground motion was used to quantify the likely effect of IRS in earthquakes. It was found that, contrary to traditional wisdom and practice, greater member strengths can result in lower frame strengths for frames under monotonic lateral loading. The structural lateral capacity of the overstrength case was reduced by 6% compared to the case using the dependable member strengths. Also, it resulted significantly different in member demands. Therefore, it is recommended that when either plastic analysis or EDA is used, that both upper and lower bounds on the likely member strength should be considered to determine the total frame strength and the member demands. Results of push-pull analysis under displacement control showed that for IRS ratio, gamma < 0.5 and axial compressive force ratio, N*/Ns, up to 0.5, IRS did affect the structural behaviour in the first half cycle. However, the behavior in the later cycles was not significantly affected. It also showed that the effect of initial residual stresses in the frame was less significant than for the column alone when the column was subjected to similar axial compressive force. The incremental dynamic analysis results from both cantilever column and the three-storey steel frame showed that by increasing gamma = 0 to 0.5, the effect of IRS on seismic responses, based on the 50% confidence level, was less than 3% for N*/Ns, up to 0.5.
One of the great challenges facing human systems today is how to prepare for, manage, and adapt successfully to the profound and rapid changes wreaked by disasters. Wellington, New Zealand, is a capital city at significant risk of devastating earthquake and tsunami, potentially requiring mass evacuations with little or short notice. Subsequent hardship and suffering due to widespread property damage and infrastructure failure could cause large areas of the Wellington Region to become uninhabitable for weeks to months. Previous research has shown that positive health and well-being are associated with disaster-resilient outcomes. Preventing adverse outcomes before disaster strikes, through developing strengths-based skill sets in health-protective attitudes and behaviours, is increasingly advocated in disaster research, practise, and management. This study hypothesised that well-being constructs involving an affective heuristic play vital roles in pathways to resilience as proximal determinants of health-protective behaviours. Specifically, this study examined the importance of health-related quality of life and subjective well-being in motivating evacuation preparedness, measured in a community sample (n=695) drawn from the general adult population of Wellington’s isolated eastern suburbs. Using a quantitative epidemiological approach, the study measured the prevalence of key quality of life indicators (physical and mental health, emotional well-being or “Sense of Coherence”, spiritual well-being, social well-being, and life satisfaction) using validated psychometric scales; analysed the strengths of association between these indicators and the level of evacuation preparedness at categorical and continuous levels of measurement; and tested the predictive power of the model to explain the variance in evacuation preparedness activity. This is the first study known to examine multi-dimensional positive health and global well-being as resilient processes for engaging in evacuation preparedness behaviour. A cross-sectional study design and quantitative survey were used to collect self-report data on the study variables; a postal questionnaire was fielded between November 2008 and March 2009 to a sampling frame developed through multi-stage cluster randomisation. The survey response rate was 28.5%, yielding a margin of error of +/- 3.8% with 95% confidence and 80% statistical power to detect a true correlation coefficient of 0.11 or greater. In addition to the primary study variables, data were collected on demographic and ancillary variables relating to contextual factors in the physical environment (risk perception of physical and personal vulnerability to disaster) and the social environment (through the construct of self-determination), and other measures of disaster preparedness. These data are reserved for future analyses. Results of correlational and regression analyses for the primary study variables show that Wellingtonians are highly individualistic in how their well-being influences their preparedness, and a majority are taking inadequate action to build their resilience to future disaster from earthquake- or tsunami-triggered evacuation. At a population level, the conceptual multi-dimensional model of health-related quality of life and global well-being tested in this study shows a positive association with evacuation preparedness at statistically significant levels. However, it must be emphasised that the strength of this relationship is weak, accounting for only 5-7% of the variability in evacuation preparedness. No single dimension of health-related quality of life or well-being stands out as a strong predictor of preparedness. The strongest associations for preparedness are in a positive direction for spiritual well-being, emotional well-being, and life satisfaction; all involve a sense of existential meaningfulness. Spiritual well-being is the only quality of life variable making a statistically significant unique contribution to explaining the variance observed in the regression models. Physical health status is weakly associated with preparedness in a negative direction at a continuous level of measurement. No association was found at statistically significant levels for mental health status and social well-being. These findings indicate that engaging in evacuation preparedness is a very complex, holistic, yet individualised decision-making process, and likely involves highly subjective considerations for what is personally relevant. Gender is not a factor. Those 18-24 years of age are least likely to prepare and evacuation preparedness increases with age. Multidimensional health and global well-being are important constructs to consider in disaster resilience for both pre-event and post-event timeframes. This work indicates a need for promoting self-management of risk and building resilience by incorporating a sense of personal meaning and importance into preparedness actions, and for future research into further understanding preparedness motivations.
Worldwide, the numbers of people living with chronic conditions are rapidly on the rise. Chronic illnesses are enduring and often cannot be cured, requiring a strategy for long term management and intervention to prevent further exacerbation. Globally, there has been an increase in interventions using telecommunications technologies to aid patients in their home setting to manage chronic illnesses. Such interventions have often been delivered by nurses. The purpose of this research was to assess whether a particular intervention that had been successfully implemented in the United Kingdom could also be implemented in Canterbury. In particular, this research assessed the perspectives of Canterbury based practice nurses and district nurses. The findings suggest that a majority of both district and practice nurses did not view the service as compatible with their current work situation. Existing workload and concerns over funding of the proposed service were identified as potential barriers. However, the service was perceived as potentially beneficial for some, with the elderly based in rural areas, or patients with chronic mental health needs identified as more likely to benefit than others. Practice nurses expressed strong views on who should deliver such services. Given that it was identified that practice nurses already have in-depth knowledge of their patients’ health, while valuing the strong relationships established with their communities, it was suggested that patients would most benefit from locally based nurses to deliver any community based health services in the future. It was also found that teletriaging is currently widely used by practice nurses across Canterbury to meet a range of health needs, including chronic mental health needs. This suggests that the scope of teletriaging in community health and its potential and full implications are currently not well understood in New Zealand. Significant events, such as the Christchurch earthquakes indicate the potential role of teletriaging in addressing mental health issues, thereby reducing the chronic health burden in the community.
Six months after the 4 September 2010 Mw 7.1 Darfield (Canterbury) earthquake, a Mw 6.2 Christchurch (Lyttelton) aftershock struck Christchurch on the 22 February 2011. This earthquake was centred approximately 10km south-east of the Christchurch CBD at a shallow depth of 5km, resulting in intense seismic shaking within the Christchurch central business district (CBD). Unlike the 4 Sept earthquake when limited-to-moderate damage was observed in engineered reinforced concrete (RC) buildings [35], in the 22 February event a high number of RC Buildings in the Christchurch CBD (16.2 % out of 833) were severely damaged. There were 182 fatalities, 135 of which were the unfortunate consequences of the complete collapse of two mid-rise RC buildings. This paper describes immediate observations of damage to RC buildings in the 22 February 2011 Christchurch earthquake. Some preliminary lessons are highlighted and discussed in light of the observed performance of the RC building stock. Damage statistics and typical damage patterns are presented for various configurations and lateral resisting systems. Data was collated predominantly from first-hand post-earthquake reconnaissance observations by the authors, complemented with detailed assessment of the structural drawings of critical buildings and the observed behaviour. Overall, the 22 February 2011 Mw 6.2 Christchurch earthquake was a particularly severe test for both modern seismically-designed and existing non-ductile RC buildings. The sequence of earthquakes since the 4 Sept 2010, particularly the 22 Feb event has confirmed old lessons and brought to life new critical ones, highlighting some urgent action required to remedy structural deficiencies in both existing and “modern” buildings. Given the major social and economic impact of the earthquakes to a country with strong seismic engineering tradition, no doubt some aspects of the seismic design will be improved based on the lessons from Christchurch. The bar needs to and can be raised, starting with a strong endorsement of new damage-resisting, whilst cost-efficient, technologies as well as the strict enforcement, including financial incentives, of active policies for the seismic retrofit of existing buildings at a national scale.
On 4 September 2010, people in Canterbury were shaken from their beds by a major earthquake. This report tells the story of the University of Canterbury (UC), its staff and its students, as they rose to the many challenges presented by the earthquake. This report however, is intended to do more than just acknowledge their hard work and determination; it also critically reflects on the things that worked well and the aspects of the response that, in hindsight, could have been done better. Luckily major events such as this earthquake do not happen every day. UC has benefited from the many universities around the world that have shared their experiences of previous disasters. We hope that this report serves to pass forward the favour and enables others to benefit from the lessons that we have learnt from this event.
On 22 February 2011, Canterbury and its largest city Christchurch experienced its second major earthquake within six months. The region is facing major economic and organisational challenges in the aftermath of these events. Approximately 25% of all buildings in the Christchurch CBD have been “red tagged” or deemed unsafe to enter. The New Zealand Treasury estimates that the combined cost of the February earthquake and the September earthquake is approximately NZ$15 billion[2]. This paper examines the national and regional economic climate prior to the event, discusses the immediate economic implications of this event, and the challenges and opportunities faced by organisations affected by this event. In order to facilitate recovery of the Christchurch area, organisations must adjust to a new norm; finding ways not only to continue functioning, but to grow in the months and years following these earthquakes. Some organisations relocated within days to areas that have been less affected by the earthquakes. Others are taking advantage of government subsidised aid packages to help retain their employees until they can make long-term decisions about the future of their organisation. This paper is framed as a “report from the field” in order to provide insight into the early recovery scenario as it applies to organisations affected by the February 2011 earthquake. It is intended both to inform and facilitate discussion about how organisations can and should pursue recovery in Canterbury, and how organisations can become more resilient in the face of the next crisis.
Surface rupture of the previously unrecognised Greendale Fault extended west-east for ~30 km across alluvial plains west of Christchurch, New Zealand, during the Mw 7.1 Darfield (Canterbury) earthquake of September 2010. Surface rupture displacement was predominantly dextral strike-slip, averaging ~2.5 m, with maxima of ~5 m. Vertical displacement was generally less than 0.75 m. The surface rupture deformation zone ranged in width from ~30 to 300 m, and comprised discrete shears, localised bulges and, primarily, horizontal dextral flexure. About a dozen buildings, mainly single-storey houses and farm sheds, were affected by surface rupture, but none collapsed, largely because most of the buildings were relatively flexible and resilient timber-framed structures and also because deformation was distributed over a relatively wide zone. There were, however, notable differences in the respective performances of the buildings. Houses with only lightly-reinforced concrete slab foundations suffered moderate to severe structural and non-structural damage. Three other buildings performed more favourably: one had a robust concrete slab foundation, another had a shallow-seated pile foundation that isolated ground deformation from the superstructure, and the third had a structural system that enabled the house to tilt and rotate as a rigid body. Roads, power lines, underground pipes, and fences were also deformed by surface fault rupture and suffered damage commensurate with the type of feature, its orientation to the fault, and the amount, sense and width of surface rupture deformation.
On 22 February 2011,a magnitude Mw 6.3 earthquake occurred with an epicenter located near Lyttelton at about 10km from Christchurch in Canterbury region on the South Island of New Zealand (Figure 1). Since this earthquake occurred in the midst of the aftershock activity which had continued since the 4 September 2010 Darfield Earthquake occurrence, it was considered to be an aftershock of the initial earthquake. Because of the short distance to the city and the shallower depth of the epicenter, this earthquake caused more significant damage to pipelines, traffic facilities, residential houses/properties and multi-story buildings in the central business district than the September 2010 Darfield Earthquake in spite of its smaller earthquake magnitude. Unfortunately, this earthquake resulted in significant number of casualties due to the collapse of multi-story buildings and unreinforced masonry structures in the city center of Christchurch. As of 4 April, 172 casualties were reported and the final death toll is expected to be 181. While it is extremely regrettable that Christchurch suffered a terrible number of victims, civil and geotechnical engineers have this hard-to-find opportunity to learn the response of real ground from two gigantic earthquakes which occurred in less than six months from each other. From geotechnical engineering point of view, it is interesting to discuss the widespread liquefaction in natural sediments, repeated liquefaction within short period and further damage to earth structures which have been damaged in the previous earthquake. Following the earthquake, an intensive geotechnical reconnaissance was conducted to capture evidence and perishable data from this event. The team included the following members: Misko Cubrinovski (University of Canterbury, NZ, Team Leader), Susumu Yasuda (Tokyo Denki University, Japan, JGS Team Leader), Rolando Orense (University of Auckland, NZ), Kohji Tokimatsu (Tokyo Institute of Technology, Japan), Ryosuke Uzuoka (Tokushima University, Japan), Takashi Kiyota (University of Tokyo, Japan), Yasuyo Hosono (Toyohashi University of Technology, Japan) and Suguru Yamada (University of Tokyo, Japan).
In order to provide information related to seismic vulnerability of non-ductile reinforced concrete (RC) frame buildings, and as a complementary investigation on innovative feasible retrofit solutions developed in the past six years at the University of Canterbury on pre-19170 reinforced concrete buildings, a frame building representative of older construction practice was tested on the shake table. The specimen, 1/2.5 scale, consists of two 3-storey 2-bay asymmetric frames in parallel, one interior and one exterior, jointed together by transverse beams and floor slabs. The as-built (benchmark) specimen was first tested under increasing ground motion amplitudes using records from Loma Prieta Earthquake (California, 1989) and suffered significant damage at the upper floor, most of it due to lap splices failure. As a consequence, in a second stage, the specimen was repaired and modified by removing the concrete in the lap splice region, welding the column longitudinal bars, replacing the removed concrete with structural mortar, and injecting cracks with epoxy resin. The modified as-built specimen was then tested using data recorded during Darfield (New Zealand, 2010) and Maule (Chile, 2010) Earthquakes, with whom the specimen showed remarkably different responses attributed to the main variation in frequency content and duration. In this contribution, the seismic performance of the three series of experiments are presented and compared.
An as-built reinforced concrete (RC) frame building designed and constructed according to pre-1970s code design construction practice has been recently tested on the shake table at the University of Canterbury. The specimen, 1/2.5 scaled version of the original prototype, consists of two 3-storey 2-bay asymmetric frames in parallel, one interior and one exterior, jointed together by transverse beams and floor slabs. Following the benchmark test, a retrofit intervention has been proposed to rehabilitate the tested specimen. In this paper, detailed information on the assessment and design of the seismic retrofit procedure using GFRP (glass fibre reinforced polymer) materials is given for the whole frame. Hierarchy of strength and sequence of events (damage mechanisms) in the panel zone region are evaluated using a moment-axial load (M-N) interaction performance domain, according to a performance-based retrofit philosophy. Specific limit states or design objectives are targeted with attention given to both strength and deformation limits. In addition, an innovative retrofit solution using FRP anchor dowels for the corner beam-column joints with slabs is proposed. Finally, in order to provide a practical tool for engineering practice, the retrofit procedure is provided in a step-by step flowchart fashion.
Recent advances in timber design at the University of Canterbury have led to new structural systems that are appropriate for a wide range of building types, including multi-storey commercial office structures. These buildings are competitive with more traditional construction materials in terms of cost, sustainability and structural performance. This paper provides seismic design recommendations and analytical modelling approaches, appropriate for the seismic design of post-tensioned coupled timber wall systems. The models are based on existing seismic design theory for precast post-tensioned concrete, modified to more accurately account for elastic deformation of the timber wall systems and the influence of the floor system. Experimental test data from a two storey post-tensioned timber building, designed, constructed and tested at the University of Canterbury is used to validate the analytical models.