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.
Tree mortality is a fundamental process governing forest dynamics, but understanding tree mortality patterns is challenging because large, long-term datasets are required. Describing size-specific mortality patterns can be especially difficult, due to few trees in larger size classes. We used permanent plot data from Nothofagus solandri var. cliffortioides (mountain beech) forest on the eastern slopes of the Southern Alps, New Zealand, where the fates of trees on 250 plots of 0.04 ha were followed, to examine: (1) patterns of size-specific mortality over three consecutive periods spanning 30 years, each characterised by different disturbance, and (2) the strength and direction of neighbourhood crowding effects on sizespecific mortality rates. We found that the size-specific mortality function was U-shaped over the 30-year period as well as within two shorter periods characterised by small-scale pinhole beetle and windthrow disturbance. During a third period, characterised by earthquake disturbance, tree mortality was less size dependent. Small trees (,20 cm in diameter) were more likely to die, in all three periods, if surrounded by a high basal area of larger neighbours, suggesting that sizeasymmetric competition for light was a major cause of mortality. In contrast, large trees ($20 cm in diameter) were more likely to die in the first period if they had few neighbours, indicating that positive crowding effects were sometimes important for survival of large trees. Overall our results suggest that temporal variability in size-specific mortality patterns, and positive interactions between large trees, may sometimes need to be incorporated into models of forest dynamics.
A Squadron 3 Iroquois helicopter refuelling at Hagley park after an aerial tour of Christchurch and Lyttelton.
On September the 4th 2010 and February 22nd 2011 the Canterbury region of New Zealand was shaken by two massive earthquakes. This paper is set broadly within the civil defence and emergency management literature and informed by recent work on community participation and social capital in the building of resilient cities. Work in this area indicates a need to recognise both the formal institutional response to the earthquakes as well as the substantive role communities play in their own recovery. The range of factors that facilitate or hinder community involvement also needs to be better understood. This paper interrogates the assumption that recovery agencies and officials are both willing and able to engage communities who are themselves willing and able to be engaged in accordance with recovery best practice. Case studies of three community groups – CanCERN, Greening the Rubble and Gap Filler – illustrate some of the difficulties associated with becoming a community during the disaster recovery phase. Based on my own observations and experiences, combined with data from approximately 50 in-depth interviews with Christchurch residents and representatives from community groups, the Christchurch City Council, the Earthquake Commission and so on, this paper outlines some practical strategies emerging communities may use in the early disaster recovery phase that then strengthens their ability to ‘participate’ in the recovery process.
There is a critical strand of literature suggesting that there are no ‘natural’ disasters (Abramovitz, 2001; Anderson and Woodrow, 1998; Clarke, 2008; Hinchliffe, 2004). There are only those that leave us – the people - more or less shaken and disturbed. There may be some substance to this; for example, how many readers recall the 7.8 magnitude earthquake centred in Fiordland in July 2009? Because it was so far away from a major centre and very few people suffered any consequences, the number is likely to be far fewer than those who remember (all too vividly) the relatively smaller 7.1 magnitude Canterbury quake of September 4th 2010 and the more recent 6.3 magnitude February 22nd 2011 event. One implication of this construction of disasters is that seismic events, like those in Canterbury, are as much socio-political as they are geological. Yet, as this paper shows, the temptation in recovery is to tick boxes and rebuild rather than recover, and to focus on hard infrastructure rather than civic expertise and community involvement. In this paper I draw upon different models of community engagement and use Putnam’s (1995) notion of ‘social capital’ to frame the argument that ‘building bridges’ after a disaster is a complex blend of engineering, communication and collaboration. I then present the results of a qualitative research project undertaken after the September 4th earthquake. This research helps to illustrate the important connections between technical rebuilding, social capital, recovery processes and overall urban resilience.
Photos of the old Canterbury Public Library being demolished. File reference: CCL-2011-09-29-librarydemolition06 From the collection of Christchurch City Libraries.
File reference: CCL-2011-08-12-CanterburyPublic Library pre-demolition-033 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton following the February 22 earthquake. File reference: CCL-2011-05-24--Loons-LYP1120500 From the collection of Christchurch City Libraries
Photos taken at Gap Filler fair on April 9 following the February 22 earthquake. www.gapfiller.org.nz/ File reference: CCL-2011-04-08-Addington-Gapfiller-003.jpg From the collection of Christchurch City Libraries
Photos taken in Bishopdale Library on April 8 following the February 22 earthquake. File reference: CCL-2011-04-08-Bisopdale-After-The-Earthquake-IMG_0450 From the collection of Christchurch City Libraries
Photos taken in Bishopdale Library on April 8 following the February 22 earthquake. File reference: CCL-2011-04-08-Bisopdale-After-The-Earthquake-IMG_0454 From the collection of Christchurch City Libraries
Photos taken in Bishopdale Library on April 8 following the February 22 earthquake. File reference: CCL-2011-04-08-Bisopdale-After-The-Earthquake-IMG_0447 From the collection of Christchurch City Libraries
File reference: CCL-2011-04-08-Lyttelton-Library-P1110823 From the collection of Christchurch City Libraries Photos of Lyttelton Library on Friday 8 April, the day it re-opened after the February 22 earthquake.
File reference: CCL-2011-04-08-Lyttelton-Library-P1110824 From the collection of Christchurch City Libraries Photos of Lyttelton Library on Friday 8 April, the day it re-opened after the February 22 earthquake.
Photos taken of the Mobile Library on March 31, 2011 following the February 22 earthquake. File reference: CCL-2011-03-31-Mobile-After-The-Earthquake-NB Parkland 022 From the collection of Christchurch City Libraries
Photos taken of the Mobile Library on March 31, 2011 following the February 22 earthquake. File reference: CCL-2011-03-31-Mobile-After-The-Earthquake-NB Parkland 024 From the collection of Christchurch City Libraries
Photos taken in Parklands Library on March 31 following the February 22 earthquake. File reference: CCL-2011-03-31-New Brighton-After-The-Earthquake-NB Parkland 011 From the collection of Christchurch City Libraries
Photos taken in Lyttelton on April 19 showing the demolition of buildings on London Street, Lyttelton, following the February 22 earthquake. File reference: CCL-2011-04-19-London-Street-Demolition-IMG_0195 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton on April 19 showing the demolition of buildings on London Street, Lyttelton, following the February 22 earthquake. File reference: CCL-2011-04-19-London-Street-Demolition-IMG_0180 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton on April 19 showing the demolition of buildings on London Street, Lyttelton, following the February 22 earthquake. File reference: CCL-2011-04-19-London-Street-Demolition-IMG_0164 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton showing the demolition of various buildings following the February 22 earthquake. File reference: CCL-2011-05-20-Lyttelton-Demolition-P1120471 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton showing the demolition of various buildings following the February 22 earthquake. File reference: CCL-2011-04-29-Lyttelton-Demolition-P1120217 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton showing the demolition at various locations following the February 22 earthquake. File reference: CCL-2011-05-20-Lyttelton-Demolition-P1120473 From the collection of Christchurch City Libraries.
Photos taken in Lyttelton following the February 22 earthquake. File ref: CCL-2011-03-05-After-The-Earthquake-P1110585 From the collection of Christchurch City Libraries
Photos taken in Lyttelton following the February 22 earthquake. File ref: CCL-2011-03-05-After-The-Earthquake-P1110570 From the collection of Christchurch City Libraries
Photos taken in Lyttelton following the February 22 earthquake. File ref: CCL-2011-03-05-After-The-Earthquake-P1110571 From the collection of Christchurch City Libraries
Photos taken in Lyttelton following the February 22 earthquake. File ref: CCL-2011-03-05-After-The-Earthquake-P1110540 From the collection of Christchurch City Libraries