High-quality ground motion records are required for engineering applications including response history analysis, seismic hazard development, and validation of physics-based ground motion simulations. However, the determination of whether a ground motion record is high-quality is poorly handled by automation with mathematical functions and can become prohibitive if done manually. Machine learning applications are well-suited to this problem, and a previous feed-forward neural network was developed (Bellagamba et al. 2019) to determine high-quality records from small crustal events in the Canterbury and Wellington regions for simulation validation. This prior work was however limited by the omission of moderate-to-large magnitude events and those from other tectonic environments, as well as a lack of explicit determination of the minimum usable frequency of the ground motion. To address these shortcomings, an updated neural network was developed to predict the quality of ground motion records for all magnitudes and all tectonic sources—active shallow crustal, subduction intraslab, and subduction interface—in New Zealand. The predictive performance of the previous feed-forward neural network was matched by the neural network in the domain of small crustal records, and this level of predictive performance is now extended to all source magnitudes and types in New Zealand making the neural network applicable to global ground motion databases. Furthermore, the neural network provides quality and minimum usable frequency predictions for each of the three orthogonal components of a record which may then be mapped into a binary quality decision or otherwise applied as desired. This framework provides flexibility for the end user to predict high-quality records with various acceptability thresholds allowing for this neural network to be used in a range of applications.
The 2013 Seddon earthquake (Mw 6.5), the 2013 Lake Grassmere earthquake (Mw 6.6), and the 2016 Kaikōura earthquake (Mw 7.8) provided an opportunity to assemble the most extensive damage database to wine storage tanks ever compiled worldwide. An overview of this damage database is presented herein based on the in-field post-earthquake damage data collected for 2058 wine storage tanks (1512 legged tanks and 546 flat-based tanks) following the 2013 earthquakes and 1401 wine storage tanks (599 legged tanks and 802 flat-based tanks) following the 2016 earthquake. Critique of the earthquake damage database revealed that in 2013, 39% and 47% of the flat-based wine tanks sustained damage to their base shells and anchors respectively, while due to resilience measures implemented following the 2013 earthquakes, in the 2016 earthquake the damage to tank base shells and tank anchors of flat-based wine tanks was reduced to 32% and 23% respectively and instead damage to tank barrels (54%) and tank cones (43%) was identified as the two most frequently occurring damage modes for this type of tank. Analysis of damage data for legged wine tanks revealed that the frame-legs of legged wine tanks sustained the greatest damage percentage among different parts of legged tanks in both the 2013 earthquakes (40%) and in the 2016 earthquake (44%). Analysis of damage data and socio-economic findings highlight the need for industry-wide standards, which may have socio-economic implications for wineries.
Timber-based hybrid structures provide a prospective solution for utilizing environmentally friendly timber material in the construction of mid-rise or high-rise structures. This study mainly focuses on structural damage evaluation for a type of timber-steel hybrid structures, which incorporate prefabricated light wood frame shear walls into steel moment-resisting frames (SMRFs). The structural damage of such a hybrid structure was evaluated through shake table tests on a four-story large-scale timber-steel hybrid structure. Four ground motion records (i.e., Wenchuan earthquake, Canterbury earthquake, El-Centro earthquake, and Kobe earthquake) were chosen for the tests, with the consideration of three different probability levels (i.e., minor, moderate and major earthquakes) for each record. During the shake table tests, the hybrid structure performed quite well with visual damage only to wood shear walls. No visual damage in SMRF and the frame-to-wall connections was observed. The correlation of visual damage to seismic intensity, modal-based damage index and inter-story drift was discussed. The reported work provided a basis of knowledge for performance-based seismic design (PBSD) for such timber-based hybrid structures.
This research investigates creativity in a post-disaster setting. The data explore creativity at the intersection of the affected community of Christchurch, New Zealand and the social processes that followed the earthquakes of 2010 - 2012. Personal and contextual influences on creative ideas implemented for community or commercial benefit are also examined.
Viewed as creative, unique approaches to post-disaster problem solving were celebrated locally, nationally and internationally (Bergman, 2014; Wesener, 2015; Cloke & Conradson, 2018). Much has been written about creativity, particularly creativity in organisations and in business. However, little is known with regards to who creates after a disaster, why individuals choose to do so and what impact the post-disaster context has on their creative activity. This exploratory study draws on the literature from the fields of creativity, disasters, psychology, sociology and entrepreneurship to interpret first-hand accounts of people who acted on creative ideas in a physically and socially altered environment.
A mixed method - albeit predominantly qualitative - approach to data gathering was adopted that included interviews (n=45) with participants who had been the primary drivers of creative ideas implemented in Christchurch after September 2010 – the first major (7.1 magnitude) earthquake in a prolonged sequence of thousands of aftershocks.
Key findings include that a specific type of creativity results from the ‘collision’ between individuals and social processes activated by a disaster situation. This type of creativity could be best categorised as ‘little c’ or socially adaptive and emerges through a prosocial filter. There is wide consensus amongst creativity researchers - principally social psychologists - that for output to be considered creative it must be both novel and useful (Runco & Jaegar, 2012). There is greater tolerance for the novelty component after a disaster as novelty itself has greater utility, either as a distraction or because alternatives are few. Existing creativity models show context as input – an additional component of the creative process – but after a disaster the event itself becomes the catalyst for social processes that result in the creativity seen. Most participants demonstrated characteristics commonly associated with creativity and could be categorised as either a ‘free thinker’ and/or an ‘opportunist’. Some appear preadapted to create and thrive in unstable circumstances.
Findings from participants’ completion of a Ten Item Personality Inventory (TIPI) showed an apparent reduced need for extraversion in relation to implementing creative ventures in society. This factor, along with higher levels of agreeableness may indicate a potentially detrimental effect on the success of creative ideas established after a disaster, despite earnest intentions.
Three new models are presented to illustrate the key findings of this study. The models imply that disasters enhance both the perceived value of creativity and the desire to act creatively for prosocial ends. The models also indicate that these disaster influenced changes are likely to be temporary.
Earthquakes cause significant damage to buildings due to strong vibration of the ground. Levitating houses using magnets and electromagnets would provide a complete isolation of ground motion for protecting buildings from seismic damage. Two types of initial configuration for the electromagnet system were proposed with the same air gap (10mm) between the electromagnet and reluctance plate. Both active and passive controller are modelled to investigate the feasibility of using a vibration control system for stabilizing the magnetic system within the designed air gap (10mm) in the vertical direction. A nonlinear model for the magnetic system is derived to implement numerical simulation of structural response under the earthquake record in Christchurch Botanic Gardens on 21 February 2011. The performance of the uncontrolled and the controlled systems are compared and the optimal combination of control gains are determined for the PID active controller. Simulation results show both active PID controller with constant and nonlinear attracting force are able to provide an effective displacement control within the required air gap (+/-5mm). The maximum control force demand for the PID controller in the presence of nonlinear attracting force is 4.1kN, while the attracting force in equilibrium position is 10kN provided by the electromagnet. These results show the feasibility of levitating a house using the current electromagnet and PID controller. Finally, initial results of passive control using two permanent magnets or dampers show the structural responses can be effectively reduced and centralized to +/-1mm using a nonlinear centring barrier function.
When an “I thought I was going to die quake” occurs amidst four additional major earthquakes and 15,000 aftershocks during a sixteen-month period, it challenges people’s ability to cope and recover. Residents of Canterbury, New Zealand endured this extended, chaotic state in 2010/11; and continue to deal with lingering effects on their devastated central city, Christchurch. Stress and coping theory suggests that finding meaning in such situations can help people recover, and that religion and spirituality often play a role in post-disaster resilience. Despite this, there is very little research literature examining this phenomenon and even less that considers spirituality separate from religion. This research focuses on this underrepresented area by considering the personal spiritual or meaningful experiences of people in post-earthquake Canterbury. Data from sixteen in-depth, minimally directed interviews were thematically analyzed to understand each individual’s meaning construction and coping/recovery process and identify connective themes and patterns amongst their experiences. Four core elements of acceptance, clarity and choice, connection, and transcendence emerged from the thematic analysis to conceptualize a model of transcendent coping. Transcendent coping represents an additional type of coping in the transactional model of stress and coping, which serves to support the previous denoted problem-, emotion-, and meaning-focused coping approaches. Transcendent coping offers openness, empowerment, comfort and expansion not necessarily reliant upon theistic or religious beliefs and practices. Rather, this secular spiritual coping is inherent in everyday, mundane practices such as being in the moment, aligning to and acting from personal values, connecting to that and those who bring comfort, and experiencing transcendence in moments of awe and expansion. This research contributes to the growing interest in spirituality as an important facet of human nature that can support wellbeing in the face of stress.
<b>New Zealand has a housing crisis. High land prices and high construction costs have all contributed to unaffordable housing. Additionally, the New Zealand dream of the "quarter acre section" lifestyle that has encouraged urban sprawl throughout our major cities with increasingly unsustainable services, transport and road costs. New and exciting housing options need to be explored for urban areas. </b>
Christchurch is a city in New Zealand where urban sprawl has always been prevalent. In the wake of the 2010/2011 earthquakes sprawl increased further, relocating large suburban areas yet further away from the city centre. This has caused a greater reliance on cars, and a slower revival to the city.
Historically there is an aversion to higher density living. Perceived desirability is a large factor. The medium to high density solutions produced thus far have little regard for the concept of "home", with the use of substandard materials, and monotonous and repetitive design, and essentially falling short of addressing the needs of New Zealand's increasing population.
"A Home with a View" looks to address the needs of New Zealanders and Christchurch, through the individual tower-house within an overarching tower-housing neighbourhood development. The design as research thesis develops a medium density tower-housing neighbourhood as a mini city-scape, through the exploration of the tower-house as an intimate space to live and observe from.
Tower-housing has the potential to create a delightful, lively neighbourhood environment that contributes to quirky, new, and exciting housing options for New Zealand. The tower-house creates desire through unconventional lifestyle and highlights engaging solutions to an individual vertical housing type.
Rising disaster losses, growth in global migration, migrant labour trends, and increasingly diverse populations have serious implications for disaster resilience around the world. These issues are of particular concern in New Zealand, which is highly exposed to disaster risk and has the highest proportion of migrant workers to national population in the OECD. Since there has been no research conducted into this issue in New Zealand to date, greater understanding of the social capital used by migrant workers in specific New Zealand contexts is needed to inform more targeted and inclusive disaster risk management approaches. A New Zealand case study is used to investigate the extent and types of social capital and levels of disaster risk awareness reported by members of three Filipino migrant workers organisations catering to dairy farm, construction and aged care workers in different urban and rural Canterbury districts. Findings from (3) semi-structured interviews and (3) focus groups include consistently high reliance on bonding capital and low levels of bridging capital across all three organisations and industry sectors, and in both urban and rural contexts. The transitory, precarious residential status conveyed by temporary work visas, and the difficulty of building bridging capital with host communities has contributed to this heavy reliance on bonding capital. Social media was essential to connect workers with family and friends in other countries, while Filipino migrant workers organisations provided members with valuable access to industry and district-specific networks of other Filipino migrant workers. Linking capital varied between the three organisations, with members of the organisation set up to advocate for dairy farm workers reporting the highest levels of linking capital. Factors influencing the capacity of workers organisations to develop linking capital appeared to include motivation (establishment objectives), length of time since establishment, support from government and industry groups, urban-rural context, income levels and gender. Although aware of publicity around earthquake and tsunami risk in the Canterbury region, participants were less aware of flood risk, and expressed fatalistic attitudes to disaster risk. Workers organisations offer a valuable potential interface between CDEM Group activities and migrant worker communities, since organisation leaders were interested in accessing government support to participate (with and on behalf of members) in disaster risk planning at district and regional level. With the potential to increase disaster resilience among these vulnerable, hard to reach communities, such participation could also help to build capacity across workers organisations (within Canterbury and across the country) to develop linking capital at national, as well as regional level. However, these links will also depend on greater government and industry commitment to providing more targeted and appropriate support for migrant workers, including consideration of the cultural qualifications of staff tasked with liaising with this community.
