This dissertation combines an assemblage theory ontology of urban sociology with the concept of Bauman's 'liquid modernity' (2000, 2012). It subsequently incorporates the nascent "liquid" constructs of liquid retail, liquid legitimacy, and liquid community to analyze consumers, community, and retailscapes in a violent and impoverished inner city area that has experienced constant and dramatic change. Through this lens, ethnographic fieldwork reveals a construct called consumption lifelines, which explains how consumers and communities use market-facing resources to find and create relative stability in the midst of turbulence, whether they choose to enter, stay in or leave a highly territorialized community with contested boundaries. The study adds complexity to Bauman's concept of liquidity and the construct of urban assemblages, and it has implications for other inner city communities that are similarly affected by changing times and challenging circumstances.

A common issue with the power grid during natural disasters is low availability. Many critical applications that are required during and after natural disasters, for rescue and logistical operations require highly available power supplies. Microgrids with distributed generation resources along with the grid provide promising solutions in order to improve the availability of power supply during natural disasters. However, distributed generators (DGs) such as diesel gensets depend on lifelines such as transportation networks whose behavior during disasters affects the genset fuel delivery systems and as a result affect the availability. Renewable sources depend on natural phenomena that have both deterministic as well as stochastic aspects to their behavior, which usually results in high variability in the output. Therefore DGs require energy storage in order to make them dispatchable sources. The microgrids availability depends on the availability characteristics of its distributed generators and energy storage and their dependent infrastructure, the distribution architecture and the power electronic interfaces. This dissertation presents models to evaluate the availability of power supply from the various distributed energy resources of a microgrid during natural disasters. The stochastic behavior of the distributed generators, storage and interfaces are modeled using Markov processes and the effect of the distribution network on availability is also considered. The presented models supported by empirical data can be hence used for microgrid planning. / text

The Master of Engineering Management Project was sponsored by the Canterbury Earthquake Recovery Authority (CERA) and consisted of two phases: The first was an analysis of existing information detailing the effects of hazardous natural events on Canterbury Lifeline Utilities in the past 15 years. The aim of this “Lessons Learned” project was to produce an analysis report that identified key themes from the research, gaps in the existing data and to provide recommendations from these “Lessons Learned.” The Second phase was the development of a practical “Disaster Mitigation Guideline” that outlined lessons in the field of Emergency Sanitation. This research would build upon the first stage and would draw from international reference to develop a guideline that has practical implementation possibilities throughout the world.

Risks posed by geohazards to urban centres are constantly increasing, due to the continuous increase in population and associated infrastructure. A major risk to North Island urban centres is impacts from volcanic ashfall. This study analyses the vulnerabilities of selected New Zealand lifelines infrastructure to volcanic ash, to better understand and mitigate these risks. Telecommunications and wastewater networks are assessed, as is the vulnerability of Auckland Airport and grounded aircraft. The ability of vehicles to drive on ash covered roads is also tested, to determine the extent to which emergency services, utility providers and the public will be able to travel during and immediately after ashfall. Finally, air-conditioners have been identified as a significant vulnerability during ashfall, due to the high dependence on cooling for infrastructure and lifelines providers. These are examined to quantify the effects of ashfall on their performance. Each of the selected infrastructure types is assessed through a review of past impacts of ashfall, and experimentation either in the field or under laboratory conditions. Where appropriate, mitigation options that reduce identified vulnerabilities are considered. In most cases these options are operational rather than physical engineering solutions, and indicate pre-planning and response requirements. Key recommended mitigation options include the acquirement or strategic relocation of resources prior to ashfall, regular cleaning and maintenance of essential air conditioners during ashfall to enable their continued use, access to appropriate vehicles for utility providers to reach infrastructure, and discharge of untreated wastewater into Waitemata harbour at Orakei during ashfall on Auckland, to preserve the ability to continue treating wastewater at the Mangere treatment plant

Risks posed by geohazards to urban centres are constantly increasing, due to the continuous increase in population and associated infrastructure. A major risk to North Island urban centres is impacts from volcanic ashfall. This study analyses the vulnerabilities of selected New Zealand lifelines infrastructure to volcanic ash, to better understand and mitigate these risks. Telecommunications and wastewater networks are assessed, as is the vulnerability of Auckland Airport and grounded aircraft. The ability of vehicles to drive on ash covered roads is also tested, to determine the extent to which emergency services, utility providers and the public will be able to travel during and immediately after ashfall. Finally, air-conditioners have been identified as a significant vulnerability during ashfall, due to the high dependence on cooling for infrastructure and lifelines providers. These are examined to quantify the effects of ashfall on their performance. Each of the selected infrastructure types is assessed through a review of past impacts of ashfall, and experimentation either in the field or under laboratory conditions. Where appropriate, mitigation options that reduce identified vulnerabilities are considered. In most cases these options are operational rather than physical engineering solutions, and indicate pre-planning and response requirements. Key recommended mitigation options include the acquirement or strategic relocation of resources prior to ashfall, regular cleaning and maintenance of essential air conditioners during ashfall to enable their continued use, access to appropriate vehicles for utility providers to reach infrastructure, and discharge of untreated wastewater into Waitemata harbour at Orakei during ashfall on Auckland, to preserve the ability to continue treating wastewater at the Mangere treatment plant

Natural hazards are a growing risk across the globe. As regions have urbanized, single events impact greater proportions of the population, and the populations within those regions have become more dependent on infrastructure systems. Regional resilience has become closely tied to the performance of infrastructure. For a comprehensive risk assessment losses caused by lifeline outage must be considered alongside structural and nonstructural risks. Many well developed techniques quantify structural and nonstructural risk; however, there are insufficient procedures to determine the likelihood of lifeline outages. Including lifelines in seismic assessments will provide a comprehensive risk, improving a decision maker’s capacity to efficiently balance mitigation against the full spectrum of risks. An ideal lifeline risk assessment is infeasible due to the large geographic scale of lifeline systems and their system structure; these same characteristics also make them vulnerable to disruption in hazard events. Probabilistic methods provide solutions for their analysis, but many of the necessary analysis variables remain unknown. Continued research and increased collection of infrastructure data may improve the ability of advanced probabilistic methods to study and forecast performance of lifelines, but many inputs for a complete probabilistic model are likely to remain unknown. This thesis recognizes these barriers to assessment and proposes a methodology that uses consequences to simplify analysis of lifeline systems. Risk is often defined as the product of probability of failure and consequence. Many assessments study the probability of failure and then consider the consequence. This thesis proposes the opposite, studying consequence first. In a theoretical model where all information is available the difference in approach is irrelevant; the results are the same regardless of order. In the real world however, studying consequence first provides an opportunity to simplify the system assessment. The proposed methodology starts with stakeholders defining consequences that constitute ruin, and then the lifeline system is examined and simplified to components that can produce such consequences. Previously large and expansive systems can be greatly simplified and made more approachable systems to study. The simplified methodology does not result in a comprehensive risk assessment, rather it provides an abbreviated risk profile of catastrophic risk; risk that constitutes ruin. By providing an assessment of only catastrophic lifeline risk, the risk of greatest importance is measured, while smaller recoverable risk remains unknown. This methodology aligns itself with the principle of resilience, the ability to withstand shocks and rebound. Assessments can be used directly to consider mitigation options that directly address stakeholder resilience. Many of the same probabilistic issues remain, but by simplifying the process, abbreviated lifelines assessments are more feasible providing stakeholders with information to make decisions in an environment that currently is largely unknown.

Lifelines such as highways, pipelines, telecommunication lines, and powerlines provide communities with vital services, and their functionality is dependent upon the foundation soil that supports them. However, when designing the infrastructure, it can be difficult to know where to test the soil in order to give spatially representative sampling, particularly for long, lifeline structures. Finding this distance requires knowledge of the spatial correlation and/or the spatial variability of the soil parameter (stiffness, cohesion, etc.). But this correlation distance is not typically found in practice because it requires large amounts of data and the costs of retrieving that data can be high. Lack of representative sampling can lead to an overly conservative design and too much sampling can create an overly expensive sampling program. In this study, multiple tests using the geophysical method of spatial autocorrelation (SPAC) were conducted to find the soil stiffness along a 310 meter long profile. SPAC records passive surface waves which sample the underlying soil, and these surface waves can be used to create a shear wave velocity profile of the site. The spatial continuity of the stiffness (the soil velocity values) was then found using geostatistics. The geostastical tool primarily used in this study was the (semi-)variogram, but the covariance function and the correlogram are also shown. By using these tools, the spatial correlation/variability can give an estimate of the how far apart to test the foundation soil so that the data is spatially representative. In other words, finding the distance that the soil parameter is minimally correlated with itself. This study found the distance (the range of the semi-variogram) to be 70 meters for 5 meters depth, 100 meters for 10 to 15 meters depth, and 90 meters for 30 meters depth.

The functionality of the transportation network following an earthquake event is critical for post-earthquake response and long-term recovery. The likely performance of a transportation network can be evaluated through a detailed seismic risk assessment. This paper presents an assessment of the seismic risk to the transportation network in the City of Charleston and the surrounding counties to support emergency response and the development of mitigation strategies and emergency planning efforts (such as lifeline selections). This study includes an inventory analysis of the 375 bridges in the Charleston area, and convolution of the seismic hazard with fragility curves analytically derived for classes of bridges common to this part of the country, damage-functionality relationships, and replacement cost estimates using relevant region-specific data. Using state-of-the-art tools, the distribution of potential bridge damage and functionality is evaluated for several scenario events, in order to aid in the identification of emergency routes and assess areas for investment in retrofit. Additionally, a sensitivity study is conducted to determine the criticality of a few of the different input models. Initial estimates of economic losses are assessed and preliminary recommendations for prioritizing retrofit are presented.

The goal of this study is to develop probabilistically based empirical correlations for seismic performance assessment of buried pipelines. Within the scope of these research efforts, pipeline performance case histories have been compiled from Duzce city after Duzce earthquake. The characteristics of Duzce water supply and distribution system with the earthquake damage on the system were studied. Correlations of the damage patterns with the water distribution system, earthquake and geotechnical characteristics have been developed. Moreover spatial distributions of the earthquake effects havebeen transferred into Geographic Information System (GIS) format. As a result of these studies, it was intended to define the seismic, geotechnical and structural parameters which may explain the spatial variability of the observed seismic pipeline hazard. For the development of such correlations, a maximum likelihood framework for the probabilistic assessment of seismically induced buried pipeline performance is described. A database, consisting of postearthquake field observations of buried pipeline performance after Duzce earthquake in conjunction with in-situ index test results, is used for the development of probabilistically based seismic pipeline performance correlations. As a result of careful processing of available data, the variables of the problem are selected as: liquefaction susceptibility of soil, thickness of soft soil layer if it exists, peak ground acceleration and estimated ground deformations. A limit state function is defined in terms of these variables. Repairs on the pipeline system due to earthquake are compiled with the surrounding soil and earthquake parameters and the correlations of pipeline performances with the mentioned variables are determined. Different sets of fragility curves are developed for seismic pipeline performance problem, representing various sources of uncertainty that are intrinsic to the problem. Such information is believed to be useful to utility system operators in planning a seismic retrofit or upgrade program for existing pipeline systems.

Volcanic eruptions are powerful natural events which impact strongly on society. As human populations grow and expand into volcanically active areas, their exposure and vulnerability to volcanic hazards is also increasing. Of all volcanic hazards, ashfall is the most likely to impact lifelines because of the large areas affected. The widespread dispersal of ash can cause large-scale disruption of vital infrastructure services, aviation, and primary production. Electric power supply is arguably the most crucial of modern infrastructure systems, especially considering the dependence of other sectors on electricity to maintain functionality. During and immediately after ashfalls, electric power systems are vulnerable to a number of impacts, but disruption from volcanic ash-induced insulator flashover (unintended, disruptive electrical discharge) is most common. This thesis investigates the vulnerability of electric power systems to volcanic ashfall by examining impacts to the different sectors of the modern power system and exploring appropriate mitigation strategies. Analogue laboratory trials using a pseudo (synthetic) ash are undertaken to verify the environmental, volcanological and electrical parameters that most affect electrical conductivity and therefore the flashover mechanism in these experiments. While dry ash is highly resistant to the flow of electric current, increasing moisture content, soluble salt load, and compaction (bulk density) will reduce this resistance and, in turn, increase the potential for flashover. Volcanic ash is an acute form of airborne pollution for areas downwind of active volcanoes. Results from laboratory experiments in this thesis suggest that insulator pollution (volcanic ash) performance (dielectric strength) is primarily dictated by (1) the conductivity of the ash, and (2) insulator material, profile (shape) and dimensioning. Composite polymer insulators tested herein effectively minimise sinusoidal leakage current and partial discharge activity and also exhibit higher pollution performance when compared to ceramic equivalents. Irrespective of insulator material, however, the likelihood of flashover increases significantly once the bottom surface of suspension insulator watersheds become contaminated in wet ash. The thesis investigates the vulnerability (hazard intensity/damage ratio) of electric power systems to volcanic ashfall hazards. Identification, analysis, and reduction of the risk of ashfall impacts to power networks is explored as a part of holistic volcanic risk assessment. The findings of the thesis contribute to the readiness, response and recovery protocols for large electric power systems in volcanic disasters; which directly affects the functional operation and economics of industrial and commercial society.