The 2010-2011 Canterbury earthquake sequence, and the resulting extensive data sets on damaged buildings that have been collected, provide a unique opportunity to exercise and evaluate previously published seismic performance assessment procedures. This poster provides an overview of the authors’ methodology to perform evaluations with two such assessment procedures, namely the P-58 guidelines and the REDi Rating System. P-58, produced by the Federal Emergency Management Agency (FEMA) in the United States, aims to facilitate risk assessment and decision-making by quantifying earthquake ground shaking, structural demands, component damage and resulting consequences in a logical framework. The REDi framework, developed by the engineering firm ARUP, aids stakeholders in implementing resilience-based earthquake design. Preliminary results from the evaluations are presented. These have the potential to provide insights on the ability of the assessment procedures to predict impacts using “real-world” data. However, further work remains to critically analyse these results and to broaden the scope of buildings studied and of impacts predicted.
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.
Asset management in power systems is exercised to improve network reliability to provide confidence and security for customers and asset owners. While there are well-established reliability metrics that are used to measure and manage business-as-usual disruptions, an increasing appreciation of the consequences of low-probability high-impact events means that resilience is increasingly being factored into asset management in order to provide robustness and redundancy to components and wider networks. This is particularly important for electricity systems, given that a range of other infrastructure lifelines depend upon their operation. The 2010-2011 Canterbury Earthquake Sequence provides valuable insights into electricity system criticality and resilience in the face of severe earthquake impacts. While above-ground assets are relatively easy to monitor and repair, underground assets such as cables emplaced across wide areas in the distribution network are difficult to monitor, identify faults on, and repair. This study has characterised in detail the impacts to buried electricity cables in Christchurch resulting from seismically-induced ground deformation caused primarily by liquefaction and lateral spread. Primary modes of failure include cable bending, stretching, insulation damage, joint braking and, being pulled off other equipment such as substation connections. Performance and repair data have been compiled into a detailed geospatial database, which in combination with spatial models of peak ground acceleration, peak ground velocity and ground deformation, will be used to establish rigorous relationships between seismicity and performance. These metrics will be used to inform asset owners of network performance in future earthquakes, further assess component criticality, and provide resilience metrics.
Please contact supervisor Lin Roberts at Lincoln University to request a copy of this dissertation to read.Cities around the world are becoming greener, with many striving to make their cities as green as possible. Christchurch was devastated by an Earthquake in 2011, which resulted in many fatalities. Though this impacted the city negatively, this sad event was used as an opportunity for the broken city to become a better one. The Christchurch City Council (CCC) ran an exercise called ‘Share an Idea’, which asked the public what they wanted the new city to look like. The main theme extrapolated by researchers was that people wanted the city to be greener. A draft plan was created by the CCC but was deemed not good enough and replaced by a new plan called the Blueprint Plan created by the government. Through the process of public consultation to the finalized plan and the implementation of the finalized plan, there were many changes made to the inclusion of nature into Central Christchurch’s urban regeneration. The aim of this research is to assess the role of nature in the urban regeneration of Christchurch, by evaluating the recovery process, and comparing the level of greenness the public wanted by looking at what they said in Share an Idea, and then seeing how that translated into the proposed plans, and then finally looking at what is being implemented.
Following the 22 February 2011 Christchurch earthquake a comprehensive damage survey of the unreinforced masonry (URM) building stock of Christchurch city, New Zealand was undertaken. Because of the large number of aftershocks associated with both the 2011 Christchurch earthquake and the earlier 4 September 2010 Darfield earthquake, and the close proximity of their epicentres to Christchurch city, this earthquake sequence presented a unique opportunity to assess the performance of URM buildings and the various strengthening methods used in New Zealand to increase the performance of these buildings in earthquakes. Because of the extent of data that was collected, a decision was made to initially focus exclusively on the earthquake performance of URM buildings located in the central business district (CBD) of Christchurch city. The main objectives of the data collection exercise were to document building characteristics and any seismic strengthening methods encountered, and correlate these attributes with observed earthquake damage. In total 370 URM buildings in the CBD were surveyed. Of the surveyed buildings, 62% of all URM buildings had received some form of earthquake strengthening and there was clear evidence that installed earthquake strengthening techniques in general had led to reduced damage levels. The procedure used to collect and process information associated with earthquake damage, general analysis and interpretation of the available survey data for the 370 URM buildings, the performance of earthquake strengthening techniques, and the influence of earthquake strengthening levels on observed damage are reported within. http://15ibmac.com/home/
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.
