Post February 22 Earthquake Damage PWS-2011-03-09-DSC9955
Post February 22 Earthquake Damage PWS-2011-03-09-DSC9954
Research following the 2010-2011 Canterbury earthquakes investigated the minimum vertical reinforcement required in RC walls to generate well distributed cracking in the plastic hinge region. However, the influence of the loading sequence and rate has not been fully addressed. The new minimum vertical reinforcement limits in NZS 3101:2006 (Amendment 3) include consideration of the material strengths under dynamic load rates, but these provisions have not been validated at a member or system level. A series of tests were conducted on RC prisms to investigate the effect of loading rate and sequence on the local behaviour of RC members. Fifteen axially loaded RC prisms with the designs representing the end region of RC walls were tested under various loading rates to cover the range of pseudo-static and earthquake loading scenarios. These tests will provide substantial data for understanding the local behaviour of RC members, including hysteretic load-deformation behaviour, crack patterns, failure mode, steel strain, strain rate and ductility. Recommendations will be made regarding the effect of loading rate and reinforcement content on the cracking behaviour and ductility of RC members.
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.
Well-validated liquefaction constitutive models are increasingly important as non-linear time history analyses become relatively more common in industry for key projects. Previous validation efforts of PM4Sand, a plasticity model specifically for liquefaction, have generally focused on centrifuge tests; however, pore pressure transducers installed at several free-field sites during the Canterbury Earthquake Sequence (CES) in Christchurch, New Zealand provide a relatively unique dataset to validate against. This study presents effective stress site response analyses performed in the finite difference software FLAC to examine the capability of PM4Sand to capture the generation of excess pore pressures during earthquakes. The characterization of the subsurface is primarily based on extensive cone penetration tests (CPT) carried out in Christchurch. Correlations based on penetration resistances are used to estimate soil parameters, such as relative density and shear wave velocity, which affect liquefaction behaviour. The resulting free-field FLAC model is used to estimate time histories of excess pore pressure, which are compared with records during several earthquakes in the CES to assess the suitability of PM4Sand.
Creativity that is driven by a need for physical or economic survival, which disasters are likely to inspire, raises the question of whether such creativity fits with conventional theories and perspectives of creativity. In this paper we use the opportunity afforded by the 2010-2013 Christchurch, New Zealand earthquakes to follow and assess the creative practices and responses of a number of groups and individuals. We use in-depth interviews to tease out motivations and read these against a range of theoretical propositions about creativity. In particular, we focus on the construct of “elite panic” and the degree to which this appeared to be evident in the Christchurch earthquakes context. Bureaucratic attempts to control or limit creativity were present but they did not produce a completely blanket dampening effect. Certain individuals and groups seemed to be pre-equipped to navigate or ignore potential blocks to creativity. We argue, using Geir Kaufmann’s novelty-creativity matrix and aspects of Teresa Amabile’s and Michael G. Pratt’s revised componential theory of creativity that a special form of disaster creativity does exist.
The paper examines community benefits provided by an established community garden following a major earthquake and discusses possible implications for community garden planning and design in disaster-prone cities. Recent studies show that following extreme storm events community gardens can supply food, enhance social empowerment, provide safe gathering spots, and restorative practices, to remind people of normality. However, the beneficial role played by community gardens following earthquakes is less well known. To fill this gap, the study examines the role played by a community garden in Christchurch, New Zealand, following the 2010/2011 Canterbury Earthquakes. The garden's role is evaluated based on a questionnaire-based survey and in-depth interviews with gardeners, as well as on data regarding the garden use before and after the earthquakes. Findings indicate the garden helped gardeners cope with the post-quake situation. The garden served as an important place to de-stress, share experiences, and gain community support. Garden features that reportedly supported disaster recovery include facilities that encourage social interaction and bonding such as central meeting and lunch places and communal working areas.
The September and February earthquakes were terrifying and devastating. In February, 185 people were killed (this number excludes post earthquake related deaths) and several thousand injured. Damage to infrastructure above and below ground in and around Christchurch was widespread and it will take many years and billions of dollars to rebuild. The ongoing effects of the big quakes and aftershocks are numerous, with the deepest impact being on those who lost family and friends, their livelihoods and homes. What did Cantabrians do during the days, weeks and months of uncertainty and how have we responded? Many grieved, some left, some stayed, some arrived, many shovelled (liquefaction left thousands of tons of silt to be removed from homes and streets), and some used their expertise or knowledge to help in the recovery. This book highlights just some of the projects staff and students from The Faculty of Environment, Society and Design have been involved in from September 2010 to October 2012. The work is ongoing and the plan is to publish another book to document progress and new projects.
Band Together - Concert for Canterbury www.bandtogetherforcanterbury.co.nz 23rd October 2010 Free concrete in Hagley Park following the 4th September 2010 earthquake
Telegraph Road was a straight road before the recent 7.1 magnitude earthquake. The fault ran right through here and now the road has a dramatic kink in it.
During the 21st century, New Zealand has experienced increasing public concern over the quality of the design and appearance of new developments, and their effects on the urban environment. In response to this, a number of local authorities developed a range of tools to address this issue, including urban design panels to review proposals and provide independent advice. Following the 2010 and 2011 Canterbury earthquake sequence, the commitment to achieve high quality urban design within Christchurch was given further importance, with the city facing the unprecedented challenge of rebuilding a ‘vibrant and successful city’. The rebuild and regeneration reinforced the need for independent design review, putting more focus and emphasis on the role and use of the urban design panel; first through collaboratively assisting applicants in achieving a better design outcome for their development by providing an independent set of eyes on their design; and secondly in assisting Council officers in forming their recommendations on resource consent decisions. However, there is a perception that urban design and the role of the urban design panel is not fully understood, with some stakeholders arguing that Council’s urban design requirements are adding cost and complexity to their developments. The purpose of this research was to develop a better understanding on the role of the Christchurch urban design panel post-earthquake in the central city; its direct and indirect influence on the built environment; and the deficiencies in the broader planning framework and institutional settings that it might be addressing. Ultimately, the perceived role of the Panel is understood, and there is agreement that urban design is having a positive influence on the built environment, albeit viewed differently amongst the varying groups involved. What has become clear throughout this research is that the perceived tension between the development community and urban design well and truly exists, with the urban design panel contributing towards this. This tension is exacerbated further through the cost of urban design to developers, and the drive for financial return from their investments. The panel, albeit promoting a positive experience, is simply a ‘tick box’ exercise for some, and as the research suggests, groups or professional are determining themselves what constitutes good urban design, based on their attitude, the context in which they sit and the financial constraints to incorporate good design elements. It is perhaps a bleak time for urban design, and more about building homes.
Laura, Nicola, and Debra watch a sand volcano build in the Wyn Street gutter.
This section considers forms of collaboration in situated and community projects embedded in important spatial transformation processes in New Zealand cities. It aims to shed light on specific combinations of material and semantic aspects characterising the relation between people and their environment. Contributions focus on participative urban transformations. The essays that follow concentrate on the dynamics of territorial production of associations between multiple actors belonging both to civil society and constituted authority. Their authors were directly engaged in the processes that are reported and conceptualised, thereby offering evidence gained through direct hands-on experience. Some of the investigations use case studies that are conspicuous examples of the recent post-traumatic urban development stemming from the Canterbury earthquakes of 2010-2011. More precisely, these cases belong to the early phases of the programmes of the Christchurch recovery or the Wellington seismic prevention. The relevance of these experiences for the scope of this study lies in the unprecedented height of public engagement at local, national and international levels, a commitment reached also due to the high impact, both emotional and concrete, that affected the entire society.
In the wake of the Canterbury earthquakes, one of the biggest threats to our heritage buildings is the risk of earthquakes and the associated drive to strengthen or demolish buildings. Can Small Town NZ balance the requirements of the EQPB legislation and economic realities of their places? The government’s priority is on safety of building occupants and citizens in the streets. However, maintaining and strengthening privately-owned heritage buildings is often cost prohibitive. Hence, heritage regulation has frequently been perceived as interfering with private property rights, especially when heritage buildings occupy a special place in the community becoming an important place for people (i.e. public benefits are larger than private). We investigate several case studies where building owners have been given green light to demolish heritage listed buildings to make way for modern developments. In two of the case studies developers provided evidence of unaffordable strengthening costs. A new trend that has emerged is a voluntary offer of contributing to an incentive fund to assist with heritage preservation of other buildings. This is a unique example where private owners offer incentives (via council controlled organisations) instead of it being purely the domain of the central or local governments.
The city of Christchurch, New Zealand, incurred significant damage due to a series of earthquakes in 2010 and 2011. The city had, by the late 2010s, regained economic and social normalcy after a sustained period of rebuilding and economic recovery. Through the concerted rebuilding effort, a modern central business district (CBD) with redesigned infrastructure and amenities was developed. The Christchurch rebuild was underpinned by a commitment of urban planners to an open and connected city, including the use of innovative technologies to gather, use and share data. As was the case elsewhere, the COVID-19 pandemic brought about significant disruptions to social and economic life in Christchurch. Border closures, lockdowns, trading limitations and other restrictions on movement led to changes in traditional consumer behaviors and affected the retail sector’s resilience. In this study, we used CBD pedestrian traffic data gathered from various locations to predict changes in retail spending and identify recovery implications through the lens of retail resilience. We found that the COVID-19 pandemic and its related lockdowns have driven a substantive change in the behavioral patterns of city users. The implications for resilient retail, sustainable policy and further research are explored.
A PDF copy of The Star newspaper, published on Friday 4 November 2011.
Following the Canterbury earthquake sequence of 2010-11, a large and contiguous tract of vacated ‘red zoned’ land lies alongside the lower Ōtākaro / Avon River and is known as the Avon-Ōtākaro Red Zone (AORZ). This is the second report in the Ecological Regeneration Options (ERO) project that addresses future land uses in the AORZ. The purpose of this report is to present results from an assessment of restoration opportunities conducted in April 2017. The objectives of the assessment were to identify potential benefits of ecological restoration activities across both land and water systems in the AORZ and characterise the key options for their implementation. The focus of this report is not to provide specific advice on the methods for achieving specific restoration endpoints per se. This will vary at different sites and scales with a large number of combinations possible. Rather, the emphasis is on providing an overview of the many restoration and regeneration options in their totality across the AORZ. An additional objective is to support their adequate assessment in the identification of optimum land uses and adaptive management practices for the AORZ. Participatory processes may play a useful role in assessment and stakeholder engagement by providing opportunities for social learning and the co-creation of new knowledge. We used a facilitated local knowledge based approach that generated a large quantity of reliable and site specific data in a short period of time. By inviting participation from a wide knowledge-holder network inclusivity is improved in comparison to small-group expert panel approaches. Similar approaches could be applied to other information gathering and assessment needs in the regeneration planning process. Findings from this study represent the most comprehensive set of concepts available to date to address the potential benefits of ecological regeneration in the AORZ. This is a core topic for planning to avoid missed opportunities and opportunity costs. The results identify a wide range of activities that may be applied to generate benefits for Christchurch and beyond, all involving aspects of a potential new ecology in the AORZ. These may be combined at a range of scales to create scenarios, quantify benefits, and explore the potential for synergies between different land use options. A particular challenge is acquiring the information needed within relatively short time frames. Early attention to gathering baseline data, addressing technical knowledge gaps, and developing conceptual frameworks to account for the many spatio-temporal aspects are all key activities that will assist in delivering the best outcomes. Methodologies by which these many facets can be pulled together in quantitative and comparative assessments are the focus of the final report in the ERO series.
An aerial photograph captioned by BeckerFraserPhotos, "Colombo Street beginning at the Copthorne on the left and ending just past the Christchurch Cathedral".
This panel discussion was presented by Sati Ravichandiren, President (Student Volunteer Army) The Canterbury Earthquakes Symposium, jointly hosted by the Department of the Prime Minister and Cabinet and the Christchurch City Council, was held on 29-30 November 2018 at the University of Canterbury in Christchurch. The purpose of the event was to share lessons from the Canterbury earthquakes so that New Zealand as a whole can be better prepared in future for any similar natural disasters. Speakers and presenters included Greater Christchurch Regeneration Minister, Hon Dr Megan Woods, Christchurch Mayor, Lianne Dalziel, Ngāi Tahu chief executive, Arihia Bennett, head of the public inquiry into EQC, Dame Sylvia Cartwright, urban planner specialising in disaster recovery and castrophe risk management, Dr Laurie Johnson; Christchurch NZ chief executive and former Press editor, Joanna Norris; academic researcher and designer, Barnaby Bennett; and filmmaker, Gerard Smyth. About 300 local and national participants from the public, private, voluntary sectors and academia attended the Symposium. They represented those involved in the Canterbury recovery effort, and also leaders of organisations that may be impacted by future disasters or involved in recovery efforts. The focus of the Symposium was on ensuring that we learn from the Canterbury experience and that we can apply those learnings.
During the Christchurch earthquake of February 2011, several midrise buildings of Reinforced Concrete Masonry (RCM) construction achieved performance levels in the range of life safety to near collapse levels. These buildings were subjected to seismic demands higher than the building code requirements of the time and higher than the current New Zealand Loadings Standard (NZS-1170.5:2004). Structural damage to these buildings has been documented and is currently being studied to establish lessons to be learned from their performance and how to incorporate these lessons into future RCM design and construction practices. This paper presents a case study of a six story RCM building deemed to have reached the near collapse performance level. The RCM walls on the 2nd floor failed due to toe crushing reducing the building’s lateral resistance in the east-west direction. A nonlinear dynamic analysis on a 3D model was conducted to simulate the development of the governing failure mechanism. Preliminary analysis results show that the damaged walls were initially under large compression forces from gravity loads which caused increase in their lateral strength and reduced their ductility. After toe crushing failure developed, axial instability of the model was prevented by a redistribution of gravity loads.
The Manchester Courts building was a heritage building located in central Christchurch (New Zealand) that was damaged in the Mw 7.1 Darfield earthquake on 4 September 2010 and subsequently demolished as a risk reduction exercise. Because the building was heritage listed, the decision to demolish the building resulted in strong objections from heritage supporters who were of the opinion that the building had sufficient residual strength to survive possible aftershock earthquakes. On 22 February 2011 Christchurch was struck by a severe aftershock, leading to the question of whether building demolition had proven to be the correct risk reduction strategy. Finite element analysis was used to undertake a performance-based assessment, validating the accuracy of the model using the damage observed in the building before its collapse. In addition, soil-structure interaction was introduced into the research due to the comparatively low shear wave velocity of the soil. The demolition of a landmark heritage building was a tragedy that Christchurch will never recover from, but the decision was made considering safety, societal, economic and psychological aspects in order to protect the city and its citizens. The analytical results suggest that the Manchester Courts building would have collapsed during the 2011 Christchurch earthquake, and that the collapse of the building would have resulted in significant fatalities.
On 4 September 2010, a 7.1 magnitude earthquake struck near Darfield, 40 kilometres west of Christchurch, New Zealand. The quake caused significant damage to land and buildings nearby, with damage extending to Christchurch city. On 22 February 2011, a 6.3 magnitude earthquake struck Christchurch, causing extensive and significant damage across the city and with the loss of 185 lives. Years on from these events, occasional large aftershocks continue to shake the region. Two main entomological collections were situated within close proximity to the 2010/11 Canterbury earthquakes. The Lincoln University Entomology Research Collection, which is housed on the 5th floor of a 7 storey building, was 27.5 km from the 2010 Darfield earthquake epicentre. The Canterbury Museum Entomology Collection, which is housed in the basement of a multi-storeyed heritage building, was 10 km from the 2011 Christchurch earthquake epicentre. We discuss the impacts of the earthquakes on these collections, the causes of the damage to the specimens and facilities, and subsequent efforts that were made to prevent further damage in the event of future seismic events. We also discuss the wider need for preparedness against the risks posed by natural disasters and other catastrophic events.
A PDF copy of The Star newspaper, published on Friday 9 November 2012.
A PDF copy of The Star newspaper, published on Wednesday 14 November 2012.
A PDF copy of The Star newspaper, published on Friday 7 December 2012.
The Screw Driving Sounding (SDS) method developed in Japan is a relatively new insitu testing technique to characterise soft shallow sites, typically those required for residential house construction. An SDS machine drills a rod into the ground in several loading steps while the rod is continuously rotated. Several parameters, such as torque, load and speed of penetration, are recorded at every rotation of the rod. The SDS method has been introduced in New Zealand, and the results of its application for characterising local sites are discussed in this study. A total of 164 SDS tests were conducted in Christchurch, Wellington and Auckland to validate/adjust the methodologies originally developed based on the Japanese practice. Most of the tests were conducted at sites where cone penetration tests (CPT), standard penetration tests (SPT) and borehole logs were available; the comparison of SDS results with existing information showed that the SDS method has great potential as an in-situ testing method for classifying the soils. By compiling the SDS data from 3 different cities and comparing them with the borehole logs, a soil classification chart was generated for identifying the soil type based on SDS parameters. Also, a correlation between fines content and SDS parameters was developed and a procedure for estimating angle of internal friction of sand using SDS parameters was investigated. Furthermore, a correlation was made between the tip resistance of the CPT and the SDS data for different percentages of fines content. The relationship between the SPT N value and a SDS parameter was also proposed. This thesis also presents a methodology for identifying the liquefiable layers of soil using SDS data. SDS tests were performed in both liquefied and non-liquefied areas in Christchurch to find a representative parameter and relationship for predicting the liquefaction potential of soil. Plots were drawn of the cyclic shear stress ratios (CSR) induced by the earthquakes and the corresponding energy of penetration during SDS tests. By identifying liquefied or unliquefied layers using three different popular CPT-based methods, boundary lines corresponding to the various probabilities of liquefaction happening were developed for different ranges of fines contents using logistic regression analysis, these could then be used for estimating the liquefaction potential of soil directly from the SDS data. Finally, the drilling process involved in screw driving sounding was simulated using Abaqus software. Analysis results proved that the model successfully captured the drilling process of the SDS machine in sand. In addition, a chart to predict peak friction angles of sandy sites based on measured SDS parameters for various vertical effective stresses was formulated. As a simple, fast and economical test, the SDS method can be a reliable alternative insitu test for soil and site characterisation, especially for residential house construction.
Canterbury Earthquakes Symposium - Social Recovery 101 – Waimakariri District Council's social recovery framework and lessons learnt from the Greater Christchurch earthquakes This panel discussion was presented by Sandra James, Director (Connecting People) The Canterbury Earthquakes Symposium, jointly hosted by the Department of the Prime Minister and Cabinet and the Christchurch City Council, was held on 29-30 November 2018 at the University of Canterbury in Christchurch. The purpose of the event was to share lessons from the Canterbury earthquakes so that New Zealand as a whole can be better prepared in future for any similar natural disasters. Speakers and presenters included Greater Christchurch Regeneration Minister, Hon Dr Megan Woods, Christchurch Mayor, Lianne Dalziel, Ngāi Tahu chief executive, Arihia Bennett, head of the public inquiry into EQC, Dame Sylvia Cartwright, urban planner specialising in disaster recovery and castrophe risk management, Dr Laurie Johnson; Christchurch NZ chief executive and former Press editor, Joanna Norris; academic researcher and designer, Barnaby Bennett; and filmmaker, Gerard Smyth. About 300 local and national participants from the public, private, voluntary sectors and academia attended the Symposium. They represented those involved in the Canterbury recovery effort, and also leaders of organisations that may be impacted by future disasters or involved in recovery efforts. The focus of the Symposium was on ensuring that we learn from the Canterbury experience and that we can apply those learnings.
Canterbury Earthquakes Symposium - Ōtautahi creative spaces: Strengthening the recovery context through a collective arts-based approach This panel discussion was presented by Dr Catherine Savage, Director (Ihi Research) and Kim Morton, Director (Ihi Research) The Canterbury Earthquakes Symposium, jointly hosted by the Department of the Prime Minister and Cabinet and the Christchurch City Council, was held on 29-30 November 2018 at the University of Canterbury in Christchurch. The purpose of the event was to share lessons from the Canterbury earthquakes so that New Zealand as a whole can be better prepared in future for any similar natural disasters. Speakers and presenters included Greater Christchurch Regeneration Minister, Hon Dr Megan Woods, Christchurch Mayor, Lianne Dalziel, Ngāi Tahu chief executive, Arihia Bennett, head of the public inquiry into EQC, Dame Sylvia Cartwright, urban planner specialising in disaster recovery and castrophe risk management, Dr Laurie Johnson; Christchurch NZ chief executive and former Press editor, Joanna Norris; academic researcher and designer, Barnaby Bennett; and filmmaker, Gerard Smyth. About 300 local and national participants from the public, private, voluntary sectors and academia attended the Symposium. They represented those involved in the Canterbury recovery effort, and also leaders of organisations that may be impacted by future disasters or involved in recovery efforts. The focus of the Symposium was on ensuring that we learn from the Canterbury experience and that we can apply those learnings.
Predictive modelling provides an efficient means to analyse the coastal environment and generate knowledge for long term urban planning. In this study, the numerical models SWAN and XBeach were incorporated into the ESRI ArcGIS interface by means of the BeachMMtool. This was applied to the Greater Christchurch coastal environment to simulate geomorphological evolution through hydrodynamic forcing. Simulations were performed using the recent sea level rise predictions by the Intergovernmental Panel on Climate Change (2013) to determine whether the statutory requirements outlined in the New Zealand Coastal Policy Statement 2010 are consistent with central, regional and district designations. Our results indicate that current land use zoning in Greater Christchurch is not consistent with these predictions. This is because coastal hazard risk has not been thoroughly quantified during the process of installing the Canterbury Earthquake Recovery Authority residential red zone. However, the Christchurch City Council’s flood management area does provide an extent to which managed coastal retreat is a real option. The results of this research suggest that progradation will continue to occur along the Christchurch foreshore due to the net sediment flux retaining an onshore direction and the current hydrodynamic activity not being strong enough to move sediment offshore. However, inundation during periods of storm surge poses a risk to human habitation on low lying areas around the Avon-Heathcote Estuary and the Brooklands lagoon.
The current seismic design practice for reinforced concrete (RC) walls has been drawn into question following the unsatisfactory performance of several RC wall buildings during the Canterbury earthquakes. An overview of current research being undertaken at the University of Auckland into the seismic behaviour of RC walls is presented. The main objectives of this research project are to understand the observed performance of RC walls in Christchurch, quantify the seismic loads on RC walls, and developed improved design procedures for RC walls that will assist in revisions to the New Zealand Concrete Structures Standard. A database summarising the performance of RC wall buildings in the Christchurch CBD was collated to identify damage modes and case-study buildings. A detailed investigation is underway to verify the seismic performance of lightly reinforced concrete walls and initial numerical modeling and small-scale tests are presented in addition to details of planned experimental tests of RC walls. Numerical modelling is being used to understand the potential influence that interactions between walls and other structural elements have on the seismic response of buildings and the loads generated on RC walls. The results from finite element analysis of a severely damaged RC wall in Christchurch highlighted the effect that the floor diaphragms have on the distribution of shear stains in the wall.