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Item Open Access Electricity Distribution Resilience Framework Through West Coast Alpine Fault Secenario(2018) Liu, Leo; Austin, Andrew; Latif, Farrukh; Maina, Duncan; Shirzadi, Samad; Nair, NirmalThe poster gives an overview of the research for the funded project " Electricity Distribution Resilience Framework through West Coast Alpine Fault Scenario". This research is being undertaken through four tracks: quantification of disaster impacts, micro-grid solution to boost electricity distribution network resilience, power system optimum recovery from disasters and communication lifeline resilience and its inter-dependency to electricity. The first track aims to provided quantitative estimate on the likelihood of different levels of damage and extent of affected areas under different earthquake intensities, which is worthwhile for determining the necessary upgrading of an existing system and for emergency planning and disaster reduction preparedness, including restoration of power. Widespread sustained blackouts is highly likely to happen after an AF8 earthquake. Microgrid is a potential possibility to bring power back up within the shortest possible time frame. In collaboration with West Coast distribution system operator, the feasibility of forming microgrids on West Coast after a major earthquake is being investigated from technical perspective. Optimum distribution network restoration for Westpower network is also being undertaken. The generator’s black start capability with all available network components are examined after which critical assets required for this activity are mapped. Communication is integral for infrastructure resilience. The mechanisms by which communication networks are affected following large-scale natural disasters are studied. This research track will investigate the extent to which wireless systems can be dynamically reconfigured to provide coverage to ‘cutoff’ regions, while still maintaining acceptable levels of interference and quality of serviceItem Open Access An Overview of Economic Impact of Resilient Seismic Techonologies on Earthquake Insurance in New Zealand(2018) Zarinkamar, Shermineh; Poshdar, Mani; Quenneville, Pierre; Wilkinson, SuzanneNew Zealand's plate boundary location implies its vulnerability to earthquake hazard. Earthquakes have caused significant damage to the built environment of the country and heavily disturbed its economy. In particular, the insurance industry is constantly struck by the high financial impact of the earthquake damages. Recently, a new generation of resilient seismic technologies is making their way to the construction industry, which offers a significant damage reduction in the structural and non-structural elements of buildings. They provide a possibility of immediate occupancy after the seismic event. The economic function of such advancements, however, has not received sustained attention from the insurance industry. This paper gives an overview about potential costs and savings associated with the use of resilient seismic technologies in comparison to the conventional solutions. A special emphasis will be given to the insurance-related costs. From the presented overview, it can be indicated that the advantages of such new technologies can effectively be translated with financial returns, which will affect the insurance costs in turn. A related potential has been found in cutting the insurance premiums and pay-outs.Item Open Access Invercagill City Council Heritage Survey and Strategy(2018) Filippova, Olga; Sullivan-Taylor, Bridgette; Devery, Liz; Voss, RichardIn 2016, Invercargill City Council engaged Origin Consultants to review central city heritage buildings. 169 buildings were reassessed with 26 buildings recommended for removal. As a result, Invercargill City Council (ICC) is developing a Heritage Strategy. Community engagement An online survey for the public and a series of presentations / workshops for building owners took place in March 2018.Item Open Access FP3: Coordinated Project - Multidisciplinary Approach for a Resilient Wellington CBD(2018) Elwood, Ken; Filippova, Olga; Chandramohan, Reagan; Orchiston, Caroline; Noy, Ilan; Hopkins, John; Pastor, Jacob; Robertson, AlexWe describe the creation of a building inventory database developed for Wellington, whose ultimate aim is to assist the generation of research on the risks, impacts, and viable solutions for reducing the seismic risk of existing multi-story concrete buildings in city’s Central Business District (CBD). The database’s primary purpose is to inform a multi-disciplinary project whose aims are: (1) to provide best scientific knowledge about the expected seismic performance of concrete buildings; (2) to assess the impact of multiple building failures including the downstream consequences of associated cordoning; (3) to provide a path for seismic retrofitting that includes prioritization of retrofits and (4) to inform the design of a regulatory structure that can facilitate the reduction of risk associated with earthquake vulnerable concrete buildings as described in aims (1)-(3). In addition, the various information associated with each building within project's scope area (for example, structural system, number of stories, age, occupants, building use etc) is GIS-ready and allows users access all the information directly on mapping applications and perform queries in a GIS viewer developed specifically for the project.Item Open Access Recent Developmements of the Resilient Slip Friction Joint (RSFJ) Technology for Seismic Proofing New and Existing Buildings(2018) Hashemi, Ashkan; Darani, Farhad; Yousef-Beik, Seyed; Abadi, Hamed; Zarmani, Pouyan; Quenneville, PierreINTRODUCTION The innovative Resilient Slip Friction Joint (RSFJ) technology has recently been introduced to the NZ construction industry. This damage avoidance technology not only provides life safety, but also minimizes the earthquake-induced damage so that the building can be reoccupied quickly. The RSFJ is a friction-based damping device with a special configuration that can produce a flag-shape hysteresis. It provides the required seismic performance regardless of the material used for the main structural components. It can be used in various applications including (but are not limited to) shear walls, tension-compression braces, tension-only braces and moment resisting frames. The philosophy of design is that the inelastic behavior of the structure is provided by the RSFJs and the rest of the structural members remain elastic. This study reports on the latest development of this technology including the analysis and design procedure. RSFJ BRACE AND RSFJ TBRACE As shown in Figure 1, The RSFJ brace includes RSFJs acting in tension and compression (providing energy dissipation and self-centring) attached to a conventional timber/steel section. The brace can be connected to the frame structure using the conventional solutions such as pinned, welded or bolted connections. The telescopic mechanism of the steel sections or tubes provides the required stability.Item Open Access GMSim Viz: Automated 3D Visualization of Ground Motion Simulation and Consequent Impacts(2018) Bae, Sung Eun; Polak, Viktor; Zhu, Melody; Motha, Jason; Bradley, Brendon; Razafindrakoto, HobyOverview GMSimViz is an automation tool that produces an animated 3D visualization of geological faults, ground motion and other earthquake-related data. Typically verification of ground motion simulations involves various data visualization methods, and a 3D animation is an excellent medium to understand the nature of an earthquake. It also helps to communicate with the general public, but its production has been largely left to time-consuming manual interaction with no existing automation tool available. GMSimViz was created to fulfil this need and produces a quality 3D animation directly from the simulation data in a fully automated way. GMSimViz is published on GitHub under MIT license. A video of the result of GMSimViz is also available on Youtube(please see '5. External Sources' at the bottom for URLs and QR codes).Item Open Access Island Grid Operations and Restoration in Electricity Distribution Networks Following Large-Scale Natural Hazards(2018) Maina, Duncan; Nair, Nirmal; Shirzadi, Samad; Griffiths, Rodger; Cosma, CosminThis project is aligned to Electricity Distribution Resilience framework and funded by Resilience to Nature’s Challenges. The goal of this project is to make New Zealand’s electricity infrastructure resilient to natural disasters. Recovery in the immediate disaster aftermath is a major component in this activity. Network restoration is complex from both a strategic and technical view point. From a strategic view point, the distribution network utility should be able to optimise their available resources in terms of crews and spares to determine the best repair schedule. In this case, a priority list is determined from the viewpoint of asset criticality. Also, the interdependency between the electricity infrastructure and other critical lifeline infrastructure should be considered in developing a network restoration strategy. From the technical point of view, the network should utilize the available firm generation (assuming grid connection is lost) to either re-energise (blackstart) the network to form an island that is self-sustaining and can last for a few weeks. This is complex in nature as distributed generation connected to utility is normally designed to provide power when the grid is available. Technical analysis should be done to evaluate the capability of available generation to both energise and sustain the island. The approach taken in the ongoing work is first examination of the generator’s black start capability with all available network components after which critical assets required for this activity are mapped and this can feed into the repair priority list. This will then influence the strategic restoration strategy.Item Open Access Ground Motion Simulation Computational Workflow(2018) Bae, Sung Eun; Polak, Viktor; Lagrava, Daniel; Motha, Jason; Bradley, Brendon; Tarbali, Karim; Lee, Robin; Huang, JonneyBackground and Objective Significant portions of QuakeCoRE research require large-scale computationally-intensive numerical ground motion (GM) simulations. The amount of data and complexity of computation make the large-scale simula-tion practically impossible to run on a researcher’s workstation. QuakeCoRE started collaboration with New Zealand eScience Infrastructure (NeSI), the na-tional high performance computing (HPC) provider to gain the necessary compu-tational capacity and execution speed. In the last 12 months transition to the new supercomputing facility has begun. For the results of our workflow, refer to other posters from our research group.Item Open Access Multi-Hazards Quantitative Assessment - An Empirical Graphical Methodology(2018) Dunant, Alexandre; Davies, Tim; Bebbington, MarkAbstract: The impact of natural disasters has been increasing in the recent years. Despite developing international interest in multi-hazard events, few studies quantify the dynamic interaction that characterise these phenomena. It is argued that without taking into account the dynamic complexity of natural catastrophes, impact assessment will underestimate risk, leading to increased vulnerability and distorted emergency management priorities. The work presented herein demonstrates how we can use graphs and networks to assess the complex impact of multi-hazard scenarios. First, the combination of maximal hazard footprints and exposed nodes (e.g. infrastructure) is used to create the hazard network. Iterative simulation of the subnetwork defined by actual hazard magnitudes is then exploited to provide an estimate of the overall compounded impact from a sequence of hazards. In order to illustrate this novel method, the Kaikoura earthquake event that occurred in 2016 is used as a calibrating event to validate the method and further study the cascading events that might threaten other parts of New Zealand. The cascading hazards include numerous landslides events. The results of the impact model on the road system will then be compared with the recorded level of service following the 2016 events. This technique is intended to inform the basis of challenging scenarios for preparing communities and emergency services.Item Open Access Investigation Disaster Resilience within the Hotel Sector: an Integrative Conceptual Framework(2018) Brown, Nancy; Orchiston, Caroline; Rovins, Jane; Feldmann-Jensen, Shirley; Johnston, DavidThis research provides the hotel sector with a starting point for assessing and better understanding what disaster resilience is for hotels by identifying predictors of disaster resilience. Resilience to disaster has become the focus of much discourse, with little understanding of the nuanced difference in what makes different types of organisations resilient to disaster. Through a systematic review of literature predictors of resilience have been identified. As a first step in refining this concept for the hotel industry, the framework categorises disaster resilience components into capital resources to provide a comprehensive look at predictors of resilience and multiple ways to approach building resilience for hotels. Highlights: • This integrative framework illustrates components of disaster resilience and highlights the important role that hotels play in contributing to community disaster resilience. • A capital approach provides a starting place for discussion of many different aspects of resilience important to the hotel sector. • Capitals identified as important for disaster resilience within the hotel sector include: economic; social; human; physical; natural; and cultural. • With a multi-entry point framework management may consider a more customised approach to building resilience to disasters.Item Open Access An Example of How Community Participation can be Successfully Incorporated into the Disaster Risk Assessment Process, Aotearoa-New Zealand(Quake CoRE, 2018) Thomas, Kristie-Lee; Wilson, Thomas; Crowley, Kate; Hughes, Matthew; Davies, Tim; Jack, Helen; King, Darren; Lane, Emily; Johnston, David; Leonard, GrahamDuring disasters, exposed communities bear the brunt of impacts and are first to respond. People of these communities obtain local and/or indigenous understanding of locally-specific challenges and opportunities, which no external expert could derive alone. Community-based, participatory disaster risk assessments involve participation of people who may be directly impacted by disasters, to: encourage sharing of valuable local knowledge, empower communities and local authorities to reduce vulnerabilities and strengthen capacities, and to form Disaster Risk Reduction initiatives that are well-informed and invested in by those involved. Kristie-Lee Thomas, a Master of Disaster Risk and Resilience student at the University of Canterbury and her supervision cohort set out to assess tsunami risk to her tūrangawaewae, Wharekauri - the Chatham Islands. This assessment was carried out for, with and by the Chatham Islands community to engender community-led action to reduce future tsunami impact. The study involved: a) Hazard assessment, including an investigation of historical tsunami impacts and inundation extents preserved in local archives and Māori knowledge. b) Assessment of potential impacts on infrastructure, to evaluate resultant levels of services based on expert judgment from local infrastructure personnel to form a credible high-impact tsunami scenario. c) Sharing this information with the community to co-develop actions to reduce future tsunami impact through participatory tools during workshops. Participation of the Chatham Islands community throughout the risk assessment process produced useful and usable outcomes. The study provides a demonstrable application of how community participation can be successfully incorporated into the disaster risk assessment process.Item Open Access Preparation of a 3D Dunedin Velocity Model(2018) Sangster, Catherine; kowal, Anna; Stirling, Mark; Gorman, Andrew; Wotherspoon, LiamThe Akatore Fault is located to the southwest of Dunedin city and is thought to represent the most significant source of seismic hazard for the city. As Dunedin has not experienced a large earthquake in recorded history, modelling is the only way to estimate the likely levels of earthquake shaking that could impact the city in a future Akatore Fault earthquake. Physics-based ground motion simulations offer an explicit way to model earthquake phenomena not reliant upon past ground motion records. Numerical models that contain the physical properties known to influence seismic wave generation and propagation are critical to the modelling process. The scope of my study is to undertake groundwork for the development of such models by acquiring, processing and integrating three strategically located land seismic lines with existing borehole data, gravity data, and geological maps in the area to build a 3D seismic velocity model for the geological units of the Dunedin area. Particular focus is given to the near surface in the city, as this is the area of greatest potential human impact This poster will present: • The collection and processing of seismic data conducted as a part of this study • The reflection profiles and their interpretation • The P-wave stacking velocity models • The near-surface structures and P-wave velocities determined through refraction modelling • Multichannel analysis of surface waves at inner-city sites. • Preliminary modelling efforts The present study represents a significant step toward understanding the seismic hazard in Dunedin City.Item Open Access Simplified-Physics High Frequency Ground-Motion Simulations Using Site-Specific Parameters(2018) Vyas, Jagdish; Bradley, Brendon; Razafindrakoto, Hoby; Thomson, Ethan; Lee, RobinHybrid broadband simulation methods typically compute high-frequency portion of ground-motions using a simplified-physics approach (commonly known as “stochastic method”) using the same 1D velocity profile, anelastic attenuation profile and site-attenuation (κ0) value for all sites. However, these parameters relating to Earth structure are known to vary spatially. In this study we modify this conventional approach for high-frequency ground-shaking by using site-specific input parameters (referred to as “site-specific”) and analyze improvements over using same parameters for all sites (referred to as “generic”). First, we theoretically understand how different 1D velocity profiles, anelastic attenuation profiles and site-attenuation (κ0) values affects the Fourier Acceleration Spectrum (FAS). Then, we apply site-specific method to simulate 10 events from the 2010-2011 Canterbury earthquake sequence to assess performance against the generic approach in predicting recorded ground-motions. Our initial results suggest that the site-specific method yields a lower simulation standard deviation than generic case.Item Open Access Cylic Undrained DSS Testing of Christchurch Sands(2018) Cappellaro, Claudio; Cubrinovski, Misko; Bray, Jonathan; Chiaro, Gabriele; Riemer, Michael; Stringer, MarkEarthquake-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.Item Open Access Automated Classification of Ground Motion Record Quality Using Machine Learing(2018) Bellagamba, Xavier; Lee, Robin; Bradley, BrendonMotivation Densification of strong-motion station networks, their increased sensitivity, and the desire to use smaller magnitude data, is leading to exponentially-increasing ground motion datasets. Despite the improving reliability of seismic instrumentation, recorded ground motions are not of uniform quality, and the exponentially-increasing dataset sizes require automated quality assessment in order to be scalable. Here we propose a two-layer neural network that takes key ground motion metrics as inputs to automatically determine the quality of the records.Item Open Access Inferred Seismic Performance and Recovery of the Christchurch Water Supply Network Following the 22 February 2011 Mw 6-2 Christchurch Earthquake(2018) Bellagamba, Xavier; Bradley, Brendon; Wotherspoon, Liam; Lagrava, DanielIntroduction This poster presents the inferred initial performance and recovery of the water supply network of Christchurch following the 22 February 2011 Mw 6.2 earthquake. Results are presented in a geospatial and temporal fashion. This work strengthens the current understanding of the restoration of such a system after a disaster and quantifies the losses caused by this earthquake in respect with the Christchurch community. Figure 1 presents the topology of the water supply network as well as the spatial distribution of the buildings and their use.Item Open Access On the Relationship Between Geospatial Liquefaction-Model Performance and Quality of Geospatial Data: A Case Study of the 2010-2016 Canterbury Earthquakes(2018) Baird, Alexander; Geyin, Mertcan; Maurer, BrettGeospatial liquefaction models aim to predict liquefaction using data that is free and readily-available. This data includes (i) common ground-motion intensity measures; and (ii) geospatial parameters (e.g., among many, distance to rivers, distance to coast, and Vs30 estimated from topography) which are used to infer characteristics of the subsurface without in-situ testing. Since their recent inception, such models have been used to predict geohazard impacts throughout New Zealand (e.g., in conjunction with regional ground-motion simulations). While past studies have demonstrated that geospatial liquefaction-models show great promise, the resolution and accuracy of the geospatial data underlying these models is notably poor. As an example, mapped rivers and coastlines often plot hundreds of meters from their actual locations. This stems from the fact that geospatial models aim to rapidly predict liquefaction anywhere in the world and thus utilize the lowest common denominator of available geospatial data, even though higher quality data is often available (e.g., in New Zealand). Accordingly, this study investigates whether the performance of geospatial models can be improved using higher-quality input data. This analysis is performed using (i) 15,101 liquefaction case studies compiled from the 2010-2016 Canterbury Earthquakes; and (ii) geospatial data readily available in New Zealand. In particular, we utilize alternative, higher-quality data to estimate: locations of rivers and streams; location of coastline; depth to ground water; Vs30; and PGV. Most notably, a region-specific Vs30 model improves performance (Figs. 3-4), while other data variants generally have little-to-no effect, even when the “standard” and “high-quality” values differ significantly (Fig. 2). This finding is consistent with the greater sensitivity of geospatial models to Vs30, relative to any other input (Fig. 5), and has implications for modeling in locales worldwide where high quality geospatial data is available.Item Open Access Modelling Nonlinear Site Effects in Physics-Based Ground Motion Simulation(2018) de la Torre, Christopher; Bradley, BrendonBackground This study examines the performance of site response analysis via nonlinear total-stress 1D wave-propagation for modelling site effects in physics-based ground motion simulations of the 2010-2011 Canterbury, New Zealand earthquake sequence. This approach allows for explicit modeling of 3D ground motion phenomena at the regional scale, as well as detailed nonlinear site effects at the local scale. The approach is compared to a more commonly used empirical VS30 (30 m time-averaged shear wave velocity)-based method for computing site amplification as proposed by Graves and Pitarka (2010, 2015), and to empirical ground motion prediction via a ground motion model (GMM).Item Open Access Who Pays for a Managed Retreat? Lessons from the Christchurch Residential Red Zone(2018) Noy, IlanAfter the Christchurch earthquakes, the government declared about 8000 houses as Red Zoned, prohibiting further developments in these properties, and offering the owners to buy them out. The government provided two options for owners: the first was full payment for both land and dwelling at the 2007 property evaluation, the second was payment for land, and the rest to be paid by the owner’s insurance. Most people chose the second option. Using data from LINZ combined with data from StatNZ, this project empirically investigates what led people to choose this second option, and what were the implications of these choices for the owners’ wealth and income.Item Open Access Measuring the Impact of Insurance on Urban Recovery with Light(2018) Nguyen, CuongWe measure the longer-term effect of a major earthquake on the local economy, using night-time light intensity measured from space, and investigate whether insurance claim payments for damaged residential property affected the local recovery process. We focus on the destructive Canterbury Earthquake Sequence (CES) 2010 -2011 as our case study. Uniquely for this event, more than 95% of residential housing units were covered by insurance, but insurance payments were staggered over 5 years, enabling us to identify their local impact. We find that night-time luminosity can capture the process of recovery and describe the recovery’s determinants. We also find that insurance payments contributed significantly to the process of economic recovery after the earthquake, but delayed payments were less affective and cash settlement of claims were more effective than insurance-managed repairs in contributing to local recovery.