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Research papers, The University of Auckland Library

New Zealand's devastating Canterbury earthquakes provided an opportunity to examine the efficacy of existing regulations and policies relevant to seismic strengthening of vulnerable buildings. The mixed-methods approach adopted, comprising both qualitative and quantitative approaches, revealed that some of the provisions in these regulations pose as constraints to appropriate strengthening of earthquake-prone buildings. Those provisions include the current seismic design philosophy, lack of mandatory disclosure of seismic risks and ineffective timeframes for strengthening vulnerable buildings. Recommendations arising from these research findings and implications for pre-disaster mitigation for future earthquake and Canterbury's post-disaster reconstruction suggest: (1) a reappraisal of the requirements for earthquake engineering design and construction, (2) a review and realignment of all regulatory frameworks relevant to earthquake risk mitigation, and (3) the need to develop a national programme necessary to achieve consistent mitigation efforts across the country. These recommendations are important in order to present a robust framework where New Zealand communities such as Christchurch can gradually recover after a major earthquake disaster, while planning for pre-disaster mitigation against future earthquakes. AM - Accepted Manuscript

Research papers, University of Canterbury Library

Disasters are rare events with major consequences; yet comparatively little is known about managing employee needs in disaster situations. Based on case studies of four organisations following the devastating earthquakes of 2010 - 2011 in Christchurch, New Zealand, this paper presents a framework using redefined notions of employee needs and expectations, and charting the ways in which these influence organisational recovery and performance. Analysis of in-depth interview data from 47 respondents in four organisations highlighted the evolving nature of employee needs and the crucial role of middle management leadership in mitigating the effects of disasters. The findings have counterintuitive implications for human resource functions in a disaster, suggesting that organisational justice forms a central framework for managing organisational responses to support and engage employees for promoting business recovery.

Research papers, University of Canterbury Library

Disasters are rare events with major consequences; yet comparatively little is known about managing employee needs in disaster situations. Based on case studies of four organisations following the devastating earthquakes of 2010 - 2011 in Christchurch, New Zealand, this paper presents a framework using redefined notions of employee needs and expectations, and charting the ways in which these influence organisational recovery and performance. Analysis of in-depth interview data from 47 respondents in four organisations highlighted the evolving nature of employee needs and the crucial role of middle management leadership in mitigating the effects of disasters. The findings have counterintuitive implications for human resource functions in a disaster, suggesting that organisational justice forms a central framework for managing organisational responses to support and engage employees for promoting business recovery.

Research papers, The University of Auckland Library

Quick and reliable assessment of the condition of bridges in a transportation network after an earthquake can greatly assist immediate post-disaster response and long-term recovery. However, experience shows that available resources, such as qualified inspectors and engineers, will typically be stretched for such tasks. Structural health monitoring (SHM) systems can therefore make a real difference in this context. SHM, however, needs to be deployed in a strategic manner and integrated into the overall disaster response plans and actions to maximize its benefits. This study presents, in its first part, a framework of how this can be achieved. Since it will not be feasible, or indeed necessary, to use SHM on every bridge, it is necessary to prioritize bridges within individual networks for SHM deployment. A methodology for such prioritization based on structural and geotechnical seismic risks affecting bridges and their importance within a network is proposed in the second part. An example using the methodology application to selected bridges in the medium-sized transportation network of Wellington, New Zealand is provided. The third part of the paper is concerned with using monitoring data for quick assessment of bridge condition and damage after an earthquake. Depending on the bridge risk profile, it is envisaged that data will be obtained from either local or national seismic monitoring arrays or SHM systems installed on bridges. A method using artificial neural networks is proposed for using data from a seismic array to infer key ground motion parameters at an arbitrary bridges site. The methodology is applied to seismic data collected in Christchurch, New Zealand. Finally, how such ground motion parameters can be used in bridge damage and condition assessment is outlined. AM - Accepted manuscript

Research papers, The University of Auckland Library

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.

Research papers, Victoria University of Wellington

Heritage buildings are an important element of our urban environments, representing the hope and aspirations of a generation gone, reminding us of our achievements and our identity.  When heritage buildings suffer damage, or fall into disrepair they are either met by one of two extremes; a bulldozer or painstaking repair. If the decision to conserve defeats the bulldozer, current heritage practice favours restoration into a mausoleum-type monument to yesteryear. But what if, rather than becoming a museum, these heritage buildings could live on and become a palimpsest of history? What if the damage was embraced and embodied in the repair?  The Cathedral of the Blessed Sacrament on Barbadoes Street, Christchurch is the case study building for this thesis. Suffering damage in the Canterbury earthquakes of 2010 and 2011, the Cathedral sits in ruin waiting for decisions to be made around how it can be retained for future generations.  This thesis will propose a reconstruction for the Cathedral through the analysis of precedent examples of reconstructing damaged heritage buildings and guided by a heritage framework proposed in this thesis. The employed process will be documented as an alternative method for reconstructing other damaged heritage buildings.

Research papers, University of Canterbury Library

The potential for a gastroenteritis outbreak in a post-earthquake environment may increase because of compromised infrastructure services, contaminated liquefaction (lateral spreading and surface ejecta), and the presence of gastroenteritis agents in the drinking water network. A population in a post-earthquake environment might be seriously affected by gastroenteritis because it has a short incubation period (about 10 hours). The potential for a gastroenteritis outbreak in a post-earthquake environment may increase because of compromised infrastructure services, contaminated liquefaction (lateral spreading and surface ejecta), and the presence of gastroenteritis agents in the drinking water network. A population in a post-earthquake environment might be seriously affected by gastroenteritis because it has a short incubation period (about 10 hours). The aim of this multidisciplinary research was to retrospectively analyse the gastroenteritis prevalence following the February 22, 2011 earthquake in Christchurch. The first focus was to assess whether earthquake-induced infrastructure damage, liquefaction, and gastroenteritis agents spatially explained the recorded gastroenteritis cases over the period of 35 days following the February 22, 2011 earthquake in Christchurch. The gastroenteritis agents considered in this study were Escherichia coli found in the drinking water supply (MPN/100mL) and Non-Compliant Free Associated Chlorine (FAC-NC) (less than <0.02mg/L). The second focus was the protocols that averted a gastroenteritis outbreak at three Emergency Centres (ECs): Burnside High School Emergency Centre (BEC); Cowles Stadium Emergency Centre (CEC); and Linwood High School Emergency Centre (LEC). Using a mixed-method approach, gastroenteritis point prevalence and the considered factors were quantitatively analysed. The qualitative analysis involved interviewing 30 EC staff members. The data was evaluated by adopting the Grounded Theory (GT) approach. Spatial analysis of considered factors showed that highly damaged CAUs were statistically clustered as demonstrated by Moran’s I statistic and hot spot analysis. Further modelling showed that gastroenteritis point prevalence clustering could not be fully explained by infrastructure damage alone, and other factors influenced the recorded gastroenteritis point prevalence. However, the results of this research suggest that there was a tenuous, indirect relationship between recorded gastroenteritis point prevalence and the considered factors: earthquake-induced infrastructure damage, liquefaction and FAC-NC. Two ECs were opened as part of the post-earthquake response in areas with severe infrastructure damage and liquefaction (BEC and CEC). The third EC (CEC) provided important lessons that were learnt from the previous September 4, 2010 earthquake, and implemented after the February 22, 2011 earthquake. Two types of interwoven themes identified: direct and indirect. The direct themes were preventive protocols and indirect themes included type of EC building (school or a sports stadium), and EC staff. The main limitations of the research were Modifiable Areal Units (MAUP), data detection, and memory loss. This research provides a practical method that can be adapted to assess gastroenteritis risk in a post-earthquake environment. Thus, this mixed method approach can be used in other disaster contexts to study gastroenteritis prevalence, and can serve as an appendage to the existing framework for assessing infectious diseases. Furthermore, the lessons learnt from qualitative analysis can inform the current infectious disease management plans, designed for a post-disaster response in New Zealand and internationally Using a mixed-method approach, gastroenteritis point prevalence and the considered factors were quantitatively analysed. A damage profile was created by amalgamating different types of damage for the considered factors for each Census Area Unit (CAU) in Christchurch. The damage profile enabled the application of a variety of statistical methods which included Moran’s I , Hot Spot (HS) analysis, Spearman’s Rho, and Besag–York–Mollié Model using a range of software. The qualitative analysis involved interviewing 30 EC staff members. The data was evaluated by adopting the Grounded Theory (GT) approach. Spatial analysis of considered factors showed that highly damaged CAUs were statistically clustered as demonstrated by Moran’s I statistic and hot spot analysis. Further modelling showed that gastroenteritis point prevalence clustering could not be fully explained by infrastructure damage alone, and other factors influenced the recorded gastroenteritis point prevalence. However, the results of this research suggest that there was a tenuous, indirect relationship between recorded gastroenteritis point prevalence and the considered factors: earthquake-induced infrastructure damage, liquefaction and FAC-NC. Two ECs were opened as part of the post-earthquake response in areas with severe infrastructure damage and liquefaction (BEC and CEC). The third EC (CEC) provided important lessons that were learnt from the previous September 4, 2010 earthquake, and implemented after the February 22, 2011 earthquake. The ECs were selected to represent the Christchurch area, and were situated where potential for gastroenteritis was high. BEC represented the western side of Christchurch; whilst, CEC and LEC represented the eastern side, where the potential for gastroenteritis was high according to the outputs of the quantitative spatial modelling. Qualitative analysis from the interviews at the ECs revealed that evacuees were arriving at the ECs with gastroenteritis-like symptoms. Participants believed that those symptoms did not originate at the ECs. Two types of interwoven themes identified: direct and indirect. The direct themes were preventive protocols that included prolific use of hand sanitisers; surveillance; and the services offered. Indirect themes included the EC layout, type of EC building (school or a sports stadium), and EC staff. Indirect themes governed the quality and sustainability of the direct themes implemented, which in turn averted gastroenteritis outbreaks at the ECs. The main limitations of the research were Modifiable Areal Units (MAUP), data detection, and memory loss. It was concluded that gastroenteritis point prevalence following the February 22, 2011 earthquake could not be solely explained by earthquake-induced infrastructure damage, liquefaction, and gastroenteritis causative agents alone. However, this research provides a practical method that can be adapted to assess gastroenteritis risk in a post-earthquake environment. Creating a damage profile for each CAU and using spatial data analysis can isolate vulnerable areas, and qualitative data analysis provides localised information. Thus, this mixed method approach can be used in other disaster contexts to study gastroenteritis prevalence, and can serve as an appendage to the existing framework for assessing infectious diseases. Furthermore, the lessons learnt from qualitative analysis can inform the current infectious disease management plans, designed for a post-disaster response in New Zealand and internationally.

Research papers, Victoria University of Wellington

In the aftermath of the 2011 earthquake, a state of polycentric urbanity was thrust upon New Zealand’s second largest city. As the city-centre lay in disrepair, smaller centres started to materialise elsewhere, out of necessity. Transforming former urban peripheries and within existing suburbs into a collective, dispersed alternative to the city centre, these sub-centres prompted a range of morphological, socio-cultural and political transformations, and begged multiple questions: how to imbue these new sub-centres with gravity? How to render them a genuine alternative to the CBD? How do they operate within the wider city? How to cope with the physical and cultural transformations of this shifting urbanscape and prevent them occurring ad lib? Indeed, the success and functioning of the larger urban structure hinges upon a critical, informed response to these sub-centre urban contexts. Yet, with an unrelenting focus on the CBD rebuild - effectively a polycentric denial - little such attention has been granted.  Taking this urban condition as its premise and its provocation, this thesis investigates architecture’s role in the emergent sub-centre. It asks: what can architecture do in these urban contexts; how can architecture act upon the emergent sub-centre in a critical, catalytic fashion? Identifying this volatile condition as both an opportunity for architectural experimentation and a need for critical architectural engagement, this thesis seeks to explore the sub-centre (as an idea and actual urban context) as architecture’s project: its raison d’etre, impetus and aspiration.  These inquiries are tested through design-led research: an initial design question provoking further, broader discursive research (and indeed, seeking broader implications). The first section is a site-specific, design for Sumner, Christchurch. Titled ‘An Agora Anew’; this project - both in conception and outcome - is a speculative response to a specific sub-centre condition. The second section ‘The Sub-centre as Architecture’s Project’ explores the ideas provoked by the design project within a discursive framework. Firstly it identifies the sub-centre as a context in desperate need of architectural attention (why architecture?); secondly, it negotiates a possible agenda for architecture in this context through terms of engagement that are formal, critical and opportunistic (how architecture?): enabling it to take a position on and in the sub-centre. Lastly, a critical exegesis positions the design in regards to the broader discursive debate: critiquing it an architectural project predicated upon the idea of the sub-centre.  The implications of this design-led thesis are twofold: firstly, for architecture’s role in the sub-centre (especially to Christchurch); secondly for the possibilities of architecture’s productive engagement with the city (largely through architectural form), more generally. In a century where radical, new urban contexts (of which the sub-centre is just one) are commonplace, this type of thinking – what can architecture do in the city? - is imperative.

Research papers, University of Canterbury Library

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