In February of 2011, an earthquake destroyed the only all-weather athletics track in the city of Christchurch (New Zealand). The track has yet to be replaced, and so since the loss of the track, local Christchurch athletes have only had a grass track for training and preparation for championship events. This paper considers what effect the loss of the training facility has had on the performance of athletes from Christchurch at national championship events. Not surprisingly, the paper finds that there has been a deterioration in the performance in events that are heavily dependent upon the all-weather surface. However, somewhat more surprisingly, the loss of the track appears to have caused a significant improvement in the performance of Christchurch athletes in events that, while on the standard athletics program, are not heavily track dependent.
Knowing how to rapidly rebuild disaster-damaged infrastructure, while deciding appropriate recovery strategies and catering for future investment is a matter of core interest to government decision makers, utility providers, and business sectors. The purpose of this research is to explore the effects of decisions and outcomes for physical reconstruction on the overall recovery process of horizontal infrastructure in New Zealand using the Canterbury and Kaikoura earthquakes as cases. A mixed approach including a systematic review, questionnaire survey and semi-structured interviews is used to capture perspectives of those involved in reconstruction process and gain insights into the effect of critical elements on infrastructure downtime. Findings from this research will contribute towards advancements of a systems dynamics model considering critical decision-making variables across phases of the reconstruction process to assess how these variables affect the rebuild process and the corresponding downtime. This project will improve the ability to explore alternative resilience improvement pathways and test the efficacy of alternative means for facilitating a faster and better reconstruction process.
Earthquake-triggered soil liquefaction caused extensive damage and heavy economic losses in Christchurch during the 2010-2011 Canterbury earthquakes. The most severe manifestations of liquefaction were associated with the presence of natural deposits of clean sands and silty sands of fluvial origin. However, liquefaction resistance of fines-containing sands is commonly inferred from empirical relationships based on clean sands (i.e. sands with less than 5% fines). Hence, existing evaluation methods have poor accuracy when applied to silty sands. Also, existing methods do not quantify appropriately the influence on liquefaction resistance of soil fabric and structure, which are unique to a specific depositional environment. This study looks at the influence of fines content, soil fabric (i.e. arrangement of soil particles) and structure (e.g. layering, segregation) on the undrained cyclic behaviour and liquefaction resistance of fines-containing sandy soils from Christchurch using Direct Simple Shear (DSS) tests on soil specimens reconstituted in the laboratory with the water sedimentation technique. The poster describes experimental procedures and presents early test results on two sands retrieved at two different sites in Christchurch.
Context of the project: On 4 September 2010, 22 February 2011, 13 June 2011 and 23 December 2011 Christchurch suffered major earthquakes and aftershocks (well over 10,000) that have left the central city in ruins and many of the eastern suburbs barely habitable even now. The earthquakes on 22 February caused catastrophic loss of life with 185 people killed. The toll this has taken on the residents of Christchurch has been considerable, not least of all for the significant psychological impact and disruption it has had on the children. As the process of rebuilding the city commenced, it became clear that the arts would play a key role in maintaining our quality of life during difficult times. For me, this started with the children and the most expressive of all the art forms – music.
There is a growing awareness of the need for the earthquake engineering practice to incorporate in addition to empirical approaches in evaluation of liquefaction hazards advanced methods which can more realistically represent soil behaviour during earthquakes. Currently, this implementation is hindered by a number of challenges mainly associated with the amount of data and user-experience required for such advanced methods. In this study, we present key steps of an advanced seismic effective-stress analysis procedure, which on the one hand can be fully automated and, on the other hand, requires no additional input (at least for preliminary applications) compared to simplified cone penetration test (CPT)-based liquefaction procedures. In this way, effective-stress analysis can be routinely applied for quick, yet more robust estimations of liquefaction hazards, in a similar fashion to the simplified procedures. Important insights regarding the dynamic interactions in liquefying soils and the actual system response of a deposit can be gained from such analyses, as illustrated with the application to two sites from Christchurch, New Zealand.
Unreinforced masonry (URM) structures comprise a majority of the global built heritage. The masonry heritage of New Zealand is comparatively younger to its European counterparts. In a country facing frequent earthquakes, the URM buildings are prone to extensive damage and collapse. The Canterbury earthquake sequence proved the same, causing damage to over _% buildings. The ability to assess the severity of building damage is essential for emergency response and recovery. Following the Canterbury earthquakes, the damaged buildings were categorized into various damage states using the EMS-98 scale. This article investigates machine learning techniques such as k-nearest neighbors, decision trees, and random forests, to rapidly assess earthquake-induced building damage. The damage data from the Canterbury earthquake sequence is used to obtain the forecast model, and the performance of each machine learning technique is evaluated using the remaining (test) data. On getting a high accuracy the model is then run for building database collected for Dunedin to predict expected damage during the rupture of the Akatore fault.
This analysis employs both qualitative and quantitative approaches to identify how young adults in New Zealand aged 18-25 years old have engaged with All Right? campaign material. A survey targeting young adults returned 51 viable out of 117 responses due to participation prerequisites. From the survey, five participants elaborated on their thoughts in an in-depth interview voluntarily. Interviews were conducted with key personnel from All Right? to craft broader understanding of the initiative whilst enhancing knowledge of mental health frameworks and their application. Ciaran Fox, Lucy Daeth and Sara Epperson, who have been imperative to the success of the campaign, shared their working experience in the community and public health sector and how this intertwines to their current roles at All Right?. Discussions of key frameworks, community conversations, the development of communication strategies and how All Right? approached Canterbury publics in a post-earthquake setting provided insight to the importance of understanding community circumstance in initial crisis and the correlated secondary stressors.
On 4 September 2010, a magnitude Mw 7.1 earthquake struck the Canterbury region on the South Island of New Zealand. The epicentre of the earthquake was located in the Darfield area about 40 km west of the city of Christchurch. Extensive damage was inflicted to lifelines and residential houses due to widespread liquefaction and lateral spreading in areas close to major streams, rivers and wetlands throughout Christchurch and Kaiapoi. Unreinforced masonry buildings also suffered extensive damage throughout the region. Despite the severe damage to infrastructure and residential houses, fortunately, no deaths occurred and only two injuries were reported in this earthquake. From an engineering viewpoint, one may argue that the most significant aspects of the 2010 Darfield Earthquake were geotechnical in nature, with liquefaction and lateral spreading being the principal culprits for the inflicted damage. Following the earthquake, an intensive geotechnical reconnaissance was conducted to capture evidence and perishable data from this event. This paper summarizes the observations and preliminary findings from this early reconnaissance work.
This paper examines the consistency of seismicity and ground motion models, used for seismic hazard analysis in New Zealand, with the observations in the Canterbury earthquakes. An overview is first given of seismicity and ground motion modelling as inputs of probabilistic seismic hazard analysis, whose results form the basis for elastic response spectra in NZS1170.5:2004. The magnitude of earthquakes in the Canterbury earthquake sequence are adequately allowed for in the current NZ seismicity model, however the consideration of ‘background’ earthquakes as point sources at a minimum depth of 10km results in up to a 60% underestimation of the ground motions that such events produce. The ground motion model used in conventional NZ seismic hazard analysis is shown to provide biased predictions of response spectra (over-prediction near T=0.2s , and under-predictions at moderate-to-large vibration periods). Improved ground motion prediction can be achieved using more recent NZ-specific models.
Two projects are documented within this MEM Report: I. The first project examined what was learnt involving the critical infrastructure in the aftermath of natural disasters in the Canterbury region of New Zealand – the most prominent being the series of earthquakes between 2010 and 2011. The project identified several learning gaps, leading to recommendations for further investigations that could add significant value for the lifeline infrastructure community. II. Following the Lifeline Lesson Learnt Project, the Disaster Mitigation Guideline series was initiated with two booklets, one on Emergency Potable Water and a second on Emergency Sanitation. The key message from both projects is that we can and must learn from disasters. The projects described are part of the emergency management, and critical infrastructure learning cycles – presenting knowledge captured by others in a digestible format, enabling the lessons to be reapplied. Without these kinds of projects, there will be fewer opportunities to learn from other’s successes and failures when it comes to preparing for natural disasters.
A multi-disciplinary geo-structural-environmental engineering project funded by the Ministry of Business Innovation and Employment (MBIE) is being carried out at the University of Canterbury. The project aims at developing an eco-friendly seismic isolation foundation system which will improve the seismic performance of medium-density low-rise buildings. Such system is characterized by two main elements: 1) granulated scrap rubber mixed with gravelly soils to be placed beneath the structure, with the goal damping part of the seismic energy before it reaches the superstructure; and 2) a basement raft made of steel-fibre reinforced rubberised concrete (SFRRuC) to enhance the flexibility and toughness of the foundation, looking at better accommodating the displacement demand. In this paper, the main objectives, scope and methodology of the project will be briefly described. A literature review of the engineering properties of steel-fibre reinforced rubberised concrete (RuC) will be presented. Then, preliminary results on concrete mixes with different rubber and steel fibres content will be exhibited.
This study investigates the uncertainty of simulated earthquake ground motions for smallmagnitude events (Mw 3.5 – 5) in Canterbury, New Zealand. 148 events were simulated with specified uncertainties in: event magnitude, hypocentre location, focal mechanism, high frequency rupture velocity, Brune stress parameter, the site 30-m time-averaged shear wave velocity (Vs30), anelastic attenuation (Q) and high frequency path duration. In order to capture these uncertainties, 25 realisations for each event were generated using the Graves and Pitarka (2015) hybrid broadband simulation approach. Monte-Carlo realisations were drawn from distributions for each uncertainty, to generate a suite of simulation realisations for each event and site. The fit of the multiple simulation realisations to observations were assessed using linear mixed effects regression to generate the systematic source, path and site effects components across all ground motion intensity measure residuals. Findings show that additional uncertainties are required in each of the three source, path, and site components, however the level of output uncertainty is promising considering the input uncertainties included.
A wide range of reinforced concrete (RC) wall performance was observed following the 2010/2011 Canterbury earthquakes, with most walls performing as expected, but some exhibiting undesirable and unexpected damage and failure characteristics. A comprehensive research programme, funded by the Building Performance Branch of the New Zealand Ministry of Business, Innovation and Employment, and involving both numerical and experimental studies, was developed to investigate the unexpected damage observed in the earthquakes and provide recommendations for the design and assessment procedures for RC walls. In particular, the studies focused on the performance of lightly reinforced walls; precast walls and connections; ductile walls; walls subjected to bi-directional loading; and walls prone to out-of-plane instability. This paper summarises each research programme and provides practical recommendations for the design and assessment of RC walls based on key findings, including recommended changes to NZS 3101 and the NZ Seismic Assessment Guidelines.
Novel Gel-push sampling was employed to obtain high quality samples of Christchurch sands from the Central Business District, at sites where liquefaction was observed in 22 February 2011, and 13 June 2011 earthquakes. The results of cyclic triaxial testing on selected undisturbed specimens of typical Christchurch sands are presented and compared to empirical procedures used by practitioners. This comparison suggests cyclic triaxial data may be conservative, and the Magnitude Scaling Factor used in empirical procedures may be unconservative for highly compressible soils during near source moderate to low magnitude events. Comparison to empirical triggering curves suggests the empirical method generally estimates the cyclic strength of Christchurch sands within a reasonable degree of accuracy as a screening evaluation tool for liquefaction hazard, however for sands with moderate to high fines content it may be significantly unconservative, highlighting the need for high quality sampling and testing on important projects where seismic performance is critical.
This thesis describes research into developing a client/server ar- chitecture for a mobile Augmented Reality (AR) application. Following the earthquakes that have rocked Christchurch the city is now changed forever. CityViewAR is an existing mobile AR application designed to show how the city used to look before the earthquakes. In CityViewAR 3D virtual building models are overlaid onto video captured by a smartphone camera. However the current version of CityViewAR only allows users to browse information stored on the mobile device. In this research the author extends the CityViewAR application to a client-server model so that anyone can upload models and annotations to a server and have this information viewable on any smartphone running the application. In this thesis we describe related work on AR browser architectures, the system we developed, a user evaluation of the prototype system and directions for future work.
This paper presents insights from recent advanced laboratory testing of undisturbed and reconstituted specimens of Christchurch silty-sands. The purpose of the testing was to establish the cyclic strength of silty-sands from sites in the Central Business District (CBD), where liquefaction was observed in 4 September 2010, 22 February 2011, and 13 June 2011. Similar overall strengths were obtained from undisturbed and reconstituted tests prepared at similar densities, albeit with higher variability for the reconstituted specimens. Reconstituted specimens exhibited distinctly different response in terms of lower compressibility during initial loading cycles, and exhibited a more brittle response when large strains were mobilised, particularly for samples with high fines content. Given the lower variability in natural sample response and the possibility of age-related strength to be significant for sites not subjected to earthquakes, high quality undisturbed samples are recommended over the use of reconstituted specimens to establish the cyclic strength of natural sands.
This paper presents the ongoing development of a new 3D seismic velocity model of Canterbury, New Zealand. The model explicitly represents the Canterbury sedimentary basin, and other significant geologic horizons, which are expected to have important implications on observed ground motions. The model utilizes numerous sources of data, including 3D regional tomography with a variable-depth inferred Moho, seismic reflection survey lines, geotechnical boreholes and well logs, spectral analysis of surface waves, and CPT logs which provide velocity constraints over their respective ranges of application. The model provides P- and S-wave velocity and density (i.e. Vp, Vs and p) over a grid of input points, and is presently being utilized in broadband ground motion simulations of the 2010-2011 Canterbury earthquakes. Comparison of simulated ground motions with those observed in the 2010-2011 Canterbury earthquakes will help provide a better understanding of the salient physical processes which characterized the unique set of strong ground motions recorded in this sequence of earthquake events.
This presentation discusses recent empirical ground motion modelling efforts in New Zealand. Firstly, the active shallow crustal and subduction interface and slab ground motion prediction equations (GMPEs) which are employed in the 2010 update of the national seismic hazard model (NSHM) are discussed. Other NZ-specific GMPEs developed, but not incorporated in the 2010 update are then discussed, in particular, the active shallow crustal model of Bradley (2010). A brief comparison of the NZ-specific GMPEs with the near-source ground motions recorded in the Canterbury earthquakes is then presented, given that these recordings collectively provide a significant increase in observed strong motions in the NZ catalogue. The ground motion prediction expert elicitation process that was undertaken following the Canterbury earthquakes for active shallow crustal earthquakes is then discussed. Finally, ongoing GMPE-related activities are discussed including: ground motion and metadata database refinement, improved site characterization of strong motion station, and predictions for subduction zone earthquakes.
The Canterbury earthquakes, which involved widespread damage in the February 2011 event and ongoing aftershocks near the Christchurch central business district (CBD), presented decision-makers with many recovery challenges. This paper identifies major government decisions, challenges, and lessons in the early recovery of Christchurch based on 23 key-informant interviews conducted 15 months after the February 2011 earthquake. It then focuses on one of the most important decisions – maintaining the cordon around the heavily damaged CBD – and investigates its impacts. The cordon displaced 50,000 central city jobs, raised questions about (and provided new opportunities for) the long-term viability of downtown, influenced the number and practice of building demolitions, and affected debris management; despite being associated with substantial losses, the cordon was commonly viewed as necessary, and provided some benefits in facilitating recovery. Management of the cordon poses important lessons for planning for catastrophic urban earthquakes around the world.
On February 22, 2011, Christchurch-based journalists were jolted out of their normal work routine by a large 6.3 magnitude earthquake that killed 185 people, wrecked the city and forced reporters to reappraise their journalism. This study considers how the earthquake affected journalists’ relationship to the community, their use of sources and news selection. A theory of collective trauma is used to explain the changes that journalists made to their reporting practice. Specifically, Christchurch journalists had a greater identification and attachment to their audience post-earthquake. Journalists viewed themselves as part of the earthquake story, which prompted them to view sources differently, use those sources differently and see advocacy as a keystone of their news work after the disaster. This study adds to a growing scholarship about journalists and trauma, but focuses on what the event meant for local reporters’ choice of sources and news selection rather than measuring rates of psychological distress.
The aim of this study is to explore the main contributors and obstacles to employee learning in the context of an alliance using the framework of a complex embedded multiple-case study. The two participant alliance partner organisations (APOs) are natural competitors that have joined to respond to urgent community needs of the city of Christchurch following the major earthquakes in September 2010 and February 2011. At the moment of the in-depth interviews, it had been about four years since those events occurred. There are continuous, unexpected circumstances that still require attention. However, the alliance has an expiry date, thus reinforcing the uncertain work environment. The main enablers found were participative, collaborative learning encouraged by leaders who embraced the alliance’s “learning organisational culture”. Employees generated innovations mostly in social interaction with others, while taking on responsibility for their learning by learning from mistakes. The main obstacle found is competition, as inhibitor of collaboratively sharing their knowledge out of fear of losing their competitiveness.
The Canterbury earthquakes have generated economic demand and supply volatility, highlighting geographical and structural interdependencies. Post-earthquake reconstruction and new developments have seen skills training, relocation, recruitment and importation of skills becoming crucial for construction companies to meet demand and compete effectively. This report presents 15 case studies from a range of organisations involved in the Canterbury rebuild, exploring the business dynamics and outcomes of their resourcing initiatives. A key finding of this research is that, for many construction organisations, resourcing initiatives have become part of their organisational longer-term development strategies, rather than simply a response to ‘supply and demand’ pressures. Organisations are not relying on any single resourcing solution to drive their growth but use a combination of initiatives to create lasting business benefits, such as cost savings, improved brand and reputation, a stable and productive workforce, enhanced efficiency and staff morale, as well as improved skill levels.
The UC CEISMIC Canterbury Earthquakes Digital Archive contains tens of thousands of high value cultural heritage items related to a long series of earthquakes that hit Canterbury, New Zealand, from 2010 - 2012. The archive was built by a Digital Humanities team located at the center of the disaster in New Zealand's second largest city, Christchurch. The project quickly became complex, not only in its technical aspects but in its governance and general management. This talk will provide insight into the national and international management and governance frameworks used to successfully build and deliver the archive into operation. Issues that needed to be managed included human ethics, research ethics, stakeholder management, communications, risk management, curation and ingestion policy, copyright and content licensing, and project governance. The team drew heavily on industry-standard project management methods for the basic approach, but built their ecosystem and stakeholder trust on principles derived directly form the global digital humanities community.
This paper presents an examination of ground motion observations from 20 near-source strong motion stations during the most significant 10 events in the 2010-2011 Canterbury earthquake to examine region-specific systematic effects based on relaxing the conventional ergodic assumption. On the basis of similar site-to-site residuals, surfical geology, and geographical proximity, 15 of the 20 stations are grouped into four sub-regions: the Central Business District; and Western, Eastern, and Northern suburbs. Mean site-to-site residuals for these sub-regions then allows for the possibility of non-ergodic ground motion prediction over these sub-regions of Canterbury, rather than only at strong motion station locations. The ratio of the total non-ergodic vs. ergodic standard deviation is found to be, on average, consistent with previous studies, however it is emphasized that on a site-by-site basis the non-ergodic standard deviation can easily vary by ±20%.
This report provides an understanding of the nature of Canterbury subcontracting businesses operating in the space of earthquake reconstruction in Christchurch. It offers an in-depth look at the factors that influence the development of their capacity and capability to withstand the impact of volatile economic cycles, including the 2008 global financial crisis and the subsequent 2010/11 Canterbury earthquakes. There have been significant changes to the business models of the 13 subcontracting businesses studied since the earthquakes. These changes can be seen in the ways the case study subcontractors have adapted to cope with the changing demands that the rebuild posed. Apart from the magnitude of reconstruction works and new developments that directly affect the capacity of subcontracting businesses in Canterbury, case studies found that subcontractors’ capacity and capability to meet the demand varies and is influenced by the: subcontractors’ own unique characteristics, which are often shaped by changing circumstances in a dynamic and uncertain recovery process; and internal factors in relation to the company’s goal and employees’ needs
This article argues that teachers deserve more recognition for their roles as first responders in the immediate aftermath of a disaster and for the significant role they play in supporting students and their families through post-disaster recovery. The data are drawn from a larger study, 'Christchurch Schools Tell Their Earthquake Stories' funded by the United Nations Educational, Scientific and Cultural Organisation and the University of Auckland, in which schools were invited to record their earthquake stories for themselves and for historical archives. Data were gathered from five primary schools between 2012 and 2014. Methods concerned mainly semi-structured individual or group interviews and which were analysed thematically. The approach was sensitive, flexible and participatory with each school being able to choose its focus, participants and outcome. Participants from each school generally included the principal and a selection of teachers, students and parents. In this study, the data relating to the roles of teachers were separated out for closer analysis. The findings are presented as four themes: immediate response; returning to (new) normal; care and support; and long term effects.
In the aftermath of the 2010-2011 Canterbury earthquakes in New Zealand, the residual capacity and reparability of damaged reinforced concrete (RC) structures was an issue pertinent to building owners, insurers, and structural engineers. Three precast RC moment-resisting frame specimens were extracted during the demolition of the Clarendon Tower in Christchurch after sustaining earthquake damage. These specimens were subjected to quasi-static cyclic testing as part of a research program to determine the reparability of the building. It was concluded that the precast RC frames were able to be repaired and retrofitted to an enhanced strength capacity with no observed reduction in displacement capacity, although the frames with “shear-ductile” detailing exhibited less displacement ductility capacity and energy dissipation capacity than the more conventionally detailed RC frames. Furthermore, the cyclic test results from the earthquake-damaged RC frames were used to verify the predicted inelastic demands applied to the specimens during the 2010-2011 Canterbury earthquakes. https://www.concrete.org/publications/acistructuraljournal.aspx
Churches are an important part of New Zealand's historical and architectural heritage. Various earthquakes around the world have highlighted the significant seismic vulnerability of religious buildings, with the extensive damage that occurred to stone and clay-brick unreinforced masonry churches after the 2010-2011 Canterbury earthquakes emphasising the necessity to better understand this structural type. Consequently, a country-wide inventory of unreinforced masonry churches is here identified. After a bibliographic and archival investigation, and a 10 000 km field trip, it is estimated that currently 297 unreinforced masonry churches are present throughout New Zealand, excluding 12 churches demolished in Christchurch because of heavy damage sustained during the Canterbury earthquake sequence. The compiled database includes general information about the buildings, their architectural features and structural characteristics, and any architectural and structural transformations that have occurred in the past. Statistics about the occurrence of each feature are provided and preliminary interpretations of their role on seismic vulnerability are discussed. The list of identified churches is reported in annexes, supporting their identification and providing their address.
Following the 2010/2011 Canterbury earthquakes the seismic design of buildings with precast concrete panels has received significant attention. Although this form of construction generally performed adequately in Christchurch, there were a considerable number of precast concrete panel connection failures. This observation prompted a review of more than 4700 panel details from 108 buildings to establish representative details used in both existing and new multi-storey and low rise industrial precast concrete buildings in three major New Zealand cities of Auckland, Wellington and Christchurch. Details were collected from precast manufacturers and city councils and were categorised according to type. The detailing and quantity of each reviewed connection type in the sampled data is reported, and advantages and potential deficiencies of each connection type are discussed. The results of this survey provide a better understanding of the relative prevalence of common detailing used in precast concrete panels and guidance for the design of future experimental studies. http://www.nzsee.org.nz/publications/nzsee-quarterly-bulletin/
The sequence of earthquakes that has greatly affected Christchurch and Canterbury since September 2010 has again demonstrated the need for seismic retrofit of heritage unreinforced masonry buildings. Commencing in April 2011, the damage to unreinforced stone masonry buildings in Christchurch was assessed and recorded with the primary objective being to document the seismic performance of these structures, recognising that they constitute an important component of New Zealand’s heritage architecture. A damage statistics database was compiled by combining the results of safety evaluation placarding and post-earthquake inspections, and it was determined that the damage observed was consistent with observations previously made on the seismic performance of stone masonry structures in large earthquakes. Details are also given on typical building characteristics and on failure modes observed. Suggestions on appropriate seismic retrofit and remediation techniques are presented, in relation also to strengthening interventions that are typical for similar unreinforced stone masonry structures in Europe.
