As a critical component of the city, urban infrastructures emerge through the interactions with the socioeconomic environment. Managing the complexity behind the interactions can make the city more sustainable. By this, we mean if we provide more sustainable amenities that people desire, a greater adoption of more sustainable infrastructures will likely occur. Two categories of infrastructure have emerged in recent years as exemplars of more sustainable development: green infrastructure and transit-oriented development. At the same time, new digital tools have emerged to better predict market acceptance of these infrastructures. This dissertation employs agent-based modeling, a latent-class analysis of survey results, and an online survey to model the potential of adoption of these infrastructures and the public benefits. The principal research content of the dissertation consists of two parts. First, understanding social preference and adoption of green infrastructure (e.g., low-impact development (LID) to control storm water), and transit-oriented development (TOD) to reduce car dependence and incentivize denser land use; Second, by developing an urban model that accounts for the complexity of the urban system, the purpose is to predict the emergent property of the city (e.g., land use, water consumption, tax revenues and carbon emissions). These two aspects constitute the research content of this dissertation. The principal findings of the dissertation are: 1) the use of digital feedback tools to inform the modeling of complex urban systems; 2) the future development of the metro Atlanta area can be more compact and sustainable with implementations of LID, TOD, and the proper policy. This dissertation consists of four sections. In the first section, I have developed an agent-based model (ABM) to predict the land use pattern. The ABM is an approach suited to simulating and understanding the dynamics of the complex system. To reduce the complexity and uncertainty of the ABM, the model simulates the decisions and interaction of agents (i.e., home buyer, the developer and the local government) at the neighborhood scale. The output of the ABM serves as the baseline scenario of land use pattern for evaluating the effect of tax investment and fees on the adoption of green infrastructure designs and more compact land use patterns. Second, with the help of the ABM, I evaluated and compared the policies (i.e., impact fees, subsidy) on the adoption of green infrastructure designs and more compact land use pattern. I developed a more sustainable development (MSD) scenario that introduces an impact fee that developers must pay if they choose not to use LID (i.e., rainwater harvesting, porous pavement) to build houses or apartment homes. Model simulations show homeowners selecting apartment homes 60% of the time after 30 years of development in MSD. In contrast, only 35% homeowners selected apartment homes after 30 years of development in a business as usual (BAU) scenario where there is no impact fee for LID. The increased adoption of apartment homes results from the lower cost of using LID (i.e., rain garden, native vegetation and porous pavements) in public spaces and improved quality of life for apartment homes relative to single-family homes. The MSD scenario generates more tax revenues and water savings than does BAU. Third, as an initial effort to calibrate the home buyer’s preference for community design in the ABM, I developed an analytic model based on an existing community preference survey. The data available for this effort is from National Association of Realtors’ 2011 community preference survey. I applied a latent class choice model to this data, and discovered four classes of individuals that reveal distinctive behaviors when choosing smart growth neighborhoods, based on the interplay between aspects of community design, socioeconomic characteristics and personal attitudes. Linking the results of the latent class choice to an agent-based market diffusion model enables planners to evaluate the effectiveness of a proposed smart growth neighborhood design in inducing less sprawling development. In the fourth section, I developed a survey that focuses on preferences of metropolitan Atlanta residents for LID and TOD. With the responses collected using Mechanical Turk, I developed a latent-class residential community choice model of four distinctive classes that reveal heterogeneous preferences for community designs. Spatial distribution of the four classes was mapped out to visualize the locations of the demand for different community designs in metropolitan Atlanta. The analysis of the impact of increase in housing price on the adoption of LID and TOD shows a low risk of investing in LID and TOD in metro area. Residents are willing to adopt the community with LID and TOD as compared to the corresponding one without LID and TOD. It turns out that LID and TOD have a great potential for adoption in metro Atlanta. Further, I integrated the individual residential community choice simulation into an agent-based market diffusion model to predict the emergent land use pattern and explore polices that can drive the adoption of more compact development. Results show that the current policy requiring single-family houses to implement LID based on individual sites should be switched to one that requires community-based LID for single-family houses. Such a policy switch will lead to a higher adoption of apartment homes with LID and TOD. Lastly, I estimated a 28% carbon emission reduction from more compact development driven by LID and TOD. This thesis is the very beginning of using digital feedback tools to anticipate market responses to more sustainable development alternatives. On the basis of the progress made in this dissertation, future work is recommended in terms of the development of an integrated platform that supports the integration of individual modules (e.g., land use, traffic simulation, air quality, and water resource management) for modeling the complexity, big data analytic techniques (e.g., Twitter, GPS data, sensors) for uncovering the interdependencies between infrastructures and socioeconomic development, and the exploration of sustainability metrics for public communication to build citizen capacity for sustainable cities.

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Sustainable pavement management implies maintaining acceptable condition of pavements while also considering the tradeoff between cost, environmental impacts and social impacts of pavement investments. Typical pavement management practices only consider economic considerations, and environmental mitigation techniques are employed after the selection of the maintenance action is complete. This dissertation presents a series of papers that demonstrate the impact of decision making on the environmental impact of the pavements both at the project and network levels of pavement management. An analysis was conducted of two models that relate pavement properties to vehicle rolling resistance and fuel consumption. These models were used, along with other tools to evaluate the impact of including the use phase of a pavement into pavement lifecycle assessments. A detailed project level lifecycle assessment was conducted, and it was found that the vehicles on the pavement during the use phase contribute the most to environmental pollutants by a significant margin over other phases of the lifecycle. Thus, relatively small improvements in the factors which contribute to rolling resistance may significantly influence the environmental impacts of the pavement. Building on this, a network level lifecycle assessment method was proposed to probabilistically quantify energy consumption for a given set of expected maintenance actions. It was shown that, although maintenance actions require a certain amount of energy consumption, this energy can be offset by improved road conditions leading to reduced rolling resistance. However, this tradeoff of reduced energy consumption also includes increased costs for a given network condition. In other words, the lowest energy consumption values did not tend to fall along the line defined by minimizing the cost divided by the pavement condition. In order to demonstrate how this tradeoff should be addressed, a novel decision analysis framework was developed, and implemented on a specific pavement network. Finally, a survey of transportation professionals was evaluated to determine their optimal points within the solution space defined by minimizing costs and energy consumption while maximizing pavement condition. It was found that the solution space could be greatly reduced by implementing their responses using the proposed decision analysis framework. / Ph. D.

This dissertation assesses the long-term technological and policy implications of adapting to water constraints and climate change impacts in the energy sector. Energy systems are increasingly vulnerable to climate change and water resource variability. Yet, the majority of long-term energy infrastructure plans ignore adaptation strategy. New analytical approaches are needed to address the spatial and temporal scales relevant to both climate change and water resources. The research in this dissertation overcomes these challenges with improved engineering-economic modeling. Specifically, the conventional systems-engineering energy technology planning framework is extended to incorporate: (1) robust capacity decisions in the electricity sector in light of impacts from hydro-climatic change and uncertain environmental performance of technology options; (2) an endogenous, spatially-distributed representation of water systems and feedbacks with energy demand; and (3) multi-objective decision-making. The computational modeling framework is applied to four regional case study analyses to quantify previously unaccounted for policy-relevant interactions between water, energy and climate systems. Application of the robust adaptation planning framework to the power system in British Columbia, Canada, reveals technology configurations offering long-term operational flexibility will be needed to ensure reliability under projected climate change impacts to provincial hydropower resources and electricity demand. The imposed flexibility requirements affect the suitability of technology options, and increases the cost of long-term electricity system operation. The case study analysis then focuses on the interaction between groundwater conservation and concurrent policy aimed at reducing electricity sector carbon emissions in the water-stressed country of Saudi Arabia. Application of the novel water-energy infrastructure planning framework reveals that transitioning away from non-renewable groundwater use by the year 2050 could increase national electricity demand by more than 40 % relative to 2010 conditions, and require investments similar to strategies aimed at transitioning away from fossil fuels in the electricity sector. The research in this dissertation demonstrates the crucial need for regional planners to account for adaptation to climate change and water resource constraints when developing long-term energy strategy. / Graduate

Det råder idag en stor brist på information angående utvecklingen för gröna tak i Stockholms stad. Eftersom gröna tak har en stor potential att stödja stadens dagvattensystem, bidra till en ökad biologisk mångfald, minska buller samt förbättra luftkvalitet innebär att gröna tak stark kan kopplas till två av Sveriges miljömål nämligen god bebyggd miljö och ett rikt växt- och djurliv. På grund av denna potential vore det ofördelaktigt om gröna tak inte används fullt ut.  En inventering av gröna tak med hjälp av flygfoton har gjorts på en del av södra Stockholms stad för att avgöra hur mycket gröna tak som byggts de senaste nio åren jämfört med tidigare år. Området valdes på grund av stor åldersvariation i bebyggelsen för att kunna representera Stockholms stad som helhet bättre. Det har också genomförts 3 intervjuer, dels med representanter för Stockholms stad och dels från byggsektorn. Syftet med intervjuerna var att undersöka om det skett en ökning i byggandet samt orsaker till detta. Resultaten av inventeringen visar att det byggts lika många gröna tak de senaste nio åren som de byggts alla tidigare år i området. Intervjuerna visar på att det har skett en ökning av mängden byggda tak och att en av orsakerna till denna ökning har varit introduktionen av grönytefaktorn. Detta kan dock inte styrkas med någon befintligdata då sådan saknas för Stockholms stad som helhet. Utvecklingen för gröna tak utifrån denna studie framgår vara positiv dock för att helt kunna säkerställa gröna taks utveckling i Stockholm rekommenderas det att en mer utförlig inventering av hela Stockholms stads bestånd av gröna tak görs. / There is currently a great lack of information regarding the development of green roofs in Stockholm. Since green roofs have big potential to support the city's storm water system, contribute to increased biodiversity, reduce noise and improve air quality, green roofs can be strongly linked to two of Sweden's environmental goals, namely a good built environment and a rich plant and animal life. Because of this potential, it would be disadvantageous if green roofs were not fully used. An inventory of green roofs using aerial photos have been taken on a part of southern Stockholm to determine how much green roofs have been built over the past nine years compared to previous years. The area was chosen because of the large age variation in the buildings in order to better represent the city of Stockholm as a whole. There have also been 3 interviews conducted with representatives of the City of Stockholm and representatives from the construction sector. The purpose of the interviews was to investigate whether there has been an increase in construction and reasons for this. The results of the inventory show that as many green roofs have been built in the last nine years as has been built in the area all the previous years. The interviews show that there has been an increase in the amount of built roofs and that one of the reasons for this increase has been the introduction of the green area factor. However, this cannot be substantiated by any existing data, as such is missing for the City of Stockholm as a whole. The development for green roofs based on this study appears to be positive, however, in order to fully ensure the development of green roofs in Stockholm, it is recommended that a more detailed inventory of the entire Stockholm city stock of green roofs be made.

The most common use of reclaimed asphalt pavement (RAP) is in the lower layers of a pavement structure, where it has been proven as a valid substitute for virgin materials. Instead, the use of RAP in surface mixes is more limited, with a major concern being that the high RAP mixes may not perform as well as traditional mixes. To reduce risks of compromised performance, the use of RAP has commonly been controlled by specifications that limit the allowed amount of recycled material in the mixes. However, significant cost and environmental savings can be achieved if more RAP is included in the surface layer. This dissertation develops an approach that can be followed to incorporate more RAP in the surface mix while maintaining good performance. The approach is based on the results from three studies that looked at how to optimize the design of the mix, in terms of rutting and fatigue resistance, when more RAP is used. In the first study, a high RAP control mix and an optimized mix designed using different design compaction energy (65 and 50 gyrations respectively) were compared. The optimization process consisted in the definition of an alternative mix composition that supported the higher binder content allowed by the lower design compaction energy. Using Accelerated Pavement Testing and laboratory characterization it was possible to assess the potential of mix optimization with the objective of improving rutting resistance. The testing showed no indication that the optimized mixes would have rutting problems, supporting the implementation of the reduction of the design compaction energy level. The optimized mix exhibited a similar or superior rutting resistance in the full-scale setting, in the laboratory, and in the forensic investigation. The second part focused on the production of highly recycled surface mixes capable of performing well. To produce the mixes, a balanced mix design (BMD) methodology was used and a comparison with traditional mixes, prepared in accordance with the requirements of the Virginia Department of Transportation (VDOT) volumetric mix design, was performed. Through the BMD procedure, which featured the indirect tensile cracking test for evaluating the cracking resistance and the Asphalt Pavement Analyzer for evaluating rutting resistance, it was possible to optimize the selection of the optimum asphalt content. Also, it was possible to obtain a highly recycled mix (45% RAP) capable of achieving better overall performances than traditional mixes while carrying a large reduction in production cost. The final part evaluated the laboratory performance of four different highly recycled surface mixes to support their possible implementation in the state of Virginia. The mixes featured either 30% or 45% RAP, different asphalt contents, the use of a WMA additive, and a rejuvenator. To analyze the mixes' performance in great depth, a three-level (base, intermediate, and advanced) testing framework was defined. Each level was characterized by an increasing degree of complexity and included tests to characterize both the cracking resistance and the rutting resistance. The study aimed at investigating the features of the various laboratory tests. Through the review of the theoretical background, the evaluation of the test procedures, and statistical analysis of the results, it was possible to identify the strengths and weaknesses of each test and to provide guidelines to develop appropriate quality assessment criteria and mix design methodology. In summary, throughout this research, it was possible to observe that the respect of Superpave mix design requirements alone, with particular reference to gradation limits and volumetric properties, was not guarantee of satisfactory performance in terms of both cracking and rutting resistance. To increase the confidence in the RAP properties, increase the current recycling levels, and introduce more appropriate mix design specifications, BMD could be used (even with simple laboratory tests) to check performance-based criteria. / Doctor of Philosophy / Nowadays, transportation agencies are expected to perform a large number of pavement rehabilitation projects, while facing major limitations in budgetary funds. In order to have safe, efficient, and cost-effective roadways, the economic advantage of recycling is boosting an effort to increase the amount of RAP in asphalt mixtures. In addition, over the past decades, the environmental awareness of the transportation agencies and public increased significantly, pushing even more towards the use of new green technologies. The use of RAP became noticeable in the 1970s and its popularity increased significantly since that time. However, there are still many open questions which prevent larger uses of recycled materials, mainly related to the design methodology and the field performances of recycled mixtures. Therefore, today there is a large untapped potential that would grow even more the magnitude of pavement recycling and of the associated benefits. New design procedures, based on the support of laboratory tests to characterize the mixtures, and full-scale experiments are the tools that pavement engineers can use in order to enrich the knowledge of highly recycled road materials and grow the confidence of public agencies and contractors towards these new more sustainable solutions. Throughout this dissertation it was possible to evaluate new innovative ways of incorporating more RAP in the asphalt mixtures through the analysis of current state of the art and the proposition of new procedures.

The numerous buildings that currently require thermal rehabilitation in Romania means that substantial resources and a large number of competent people are required to carry out surveys and energy audits. However, commercial energy balance software is mostly unaffordable for those organisations involved in this process. This paper describes an energy balance programme – ENEFControl – developed to be a rapid, low cost, local tool able to assist in the choice of energy efficient solutions for buildings. To test the software, thermal and energy analyses were carried out on a 1970s built apartment block in Transylvania. Based on these analyses, three constructive scenarios were proposed for thermal rehabilitation. Compared to the performance of the analysed building, the thermal and energy performance of the retrofitted building in all three scenarios significantly improved. Since European Union accession in 2007, rapidly rising energy costs have affected the Romanian population. ENEFControl offers Romanian engineers and architects an opportunity to speed up the rehabilitation programme of buildings without the need for more expensive expertise and tools.

Pavement system plays an indispensable role in the socio-economic and sustainable development of every modern society. Yet, pavement construction and maintenance is also responsible for a significant fraction of the GHG emissions from the whole transport sector. At the same time, the extensive global pavement network entails continual investment in maintenance and rehabilitation activities. Given the evidence from previous studies, pavement maintenance has a great potential in reducing pavement-induced GHG emissions and fuel consumption. To assist the transition towards a future sustainable road infrastructure, this thesis has marked the theoretical basis of sustainable pavement maintenance management. Two approaches are discussed to offer a multi-dimensional view for future sustainability improvement in pavement maintenance practices. With the still-evolving concept of sustainability in road infrastructure, it is necessary to recognize where we are and what we need to do to develop a comprehensive management framework with the opportunities and challenges. Based on a systematic literature review, this project identifies the current stage of sustainable road infrastructure management and guides to sustainability-oriented maintenance optimization for designing top-down strategies. Meanwhile, it is not enough to only optimize the decision-making process; more bottom-up knowledge of pavement materials is required to inform better maintenance design. This thesis has focused on the self-healing property of asphalt material due to the non-negligible sustainability indications it implies. By applying neutron tomography and image processing technique, the microstructural changes during the self-healing process are analyzed with its 7-hour time-series volumetric data. The experiment has shown that different filler content has a great influence on self-healing efficiency in asphalt mastics. The results will give us the possibility to optimize asphalt self-repair, shedding a light on a new generation of sustainable asphalt pavement. The two approaches presented in this thesis offer valuable insights into sustainable road infrastructure optimization from different aspects. / I varje modernt samhälle spelar vägarna en viktig roll för socioekonomisk och hållbar utveckling. Vägnätet, med byggande och underhåll, bidrar också med en betydande del av växthusgasutsläppen från hela transportsektorn. Vägnätet kräver kontinuerliga investeringar på grund av behovet av underhåll . Tidigare studier har visat att det finns en stor potential för minskning av utsläppen av växthusgaser från vägunderhåll. Vägarnas kvalitet spelar också roll för trafikens bränsleförbrukning.  Fokus för denna avhandling är att underlätta för framtida hållbar väginfrastruktur. När det gäller den teoretiska grunden för hållbar förvaltning av vägar och underhåll av vägbeläggningar är det nödvändigt att förstå vad som är dagens aktuella teknik, och också att veta vad vi behöver utveckla för att få ett heltäckande ledningsramverk för vägunderhåll. Här finns både möjligheter och utmaningar. Baserat på en systematisk litteraturgenomgång identifierar detta projekt det aktuella läget när det gäller praktik för förvaltning av väginfrastruktur. Som ett resultat av detta presenteras olika metoder som tillämpas för en målorienterad underhållsoptimering, som måste göras top-down från den som har övergripande ansvar för vägnätet. Samtidigt räcker det inte att bara optimera beslutsprocessen, det krävs mer bottom-up kunskap i fråga om beläggningsmaterial för att förbättra metoderna för underhåll. Denna avhandling har därför också fokuserat på den självläkande egenskapen hos asfaltmaterial. Här fanns en unik möjlighet att tillämpa neutrontomografi och bildbehandlingsteknik för analyser av de mikrostrukturella förändringarna under självläkningsprocessen i asfaltmaterial, med 7-timmars tidsserievolymetriska data. Experimentet har visat att olika innehåll av fyllmedel i asfaltmastixen  har stor inverkan på självläkandets effektivitet. De två tillvägagångssätten som presenteras i denna avhandling ger värdefulla insikter om hållbar väginfrastrukturoptimering ur olika aspekter. / <p>QC 220309</p>

Rapportens syfte har varit att uppmärksamma återanvändningspotentialen hos jordmassor och hur resurseffektivitet kan optimeras i projekt Ostlänken samt stora infrastrukturprojekt i allmänhet. Det praktiska syftet med studien är att bidra till en mer hållbar masshantering i projekt Ostlänken. Denna rapport har skrivits i form av en fallstudie med två typfall där triangulering har implementerats i forsknings-metodiken för att kombinera kvalitativa med kvantitativa metoder. Kriterier för rapportens analys-metod är baserad på en samlad effektivitetsbedömning där analyserade kriterier är ekonomi, klimat och risk. Resultatet indikerar att jordmassor som transporteras med semitrailer utanför ett projektområde till en fiktiv deponi-plats är både mer kostsamt och emitterar mer CO2-ekv. jämfört med jordmassor som transporteras med dumper innanför ett projektområde för återanvändningsändamål. Analysen visar att en ökad maxlast i kombination med en kortare sträcka är det mest kostnadseffektiva alternativet. Studien belyser även vikten av att inkludera hela värdekedjan (beställare-konsult-entreprenad) och uppdatera branschens annars konservativa förhållningssätt gällande masshanteringsarbetet. / The purpose of the report is to pay attention to the reuse potential of soil masses in infrastructure projects, specifically the East Link Project and how resource efficiency can be optimized. The practical purpose of the study is to contribute to a more sustainable mass management in the East Link Project. This report has been written in the form of a case study with two types of cases where triangulation has been implemented in the research methodology to combine qualitative with quantitative methods. Criterions for the analytical method of the report are based on an overall efficiency assessment, where analyzed criterions are economy, climate and risk. The result indicates that excavated soil masses that are transported by semi-trailers outside the project area to a fictional landfill are costlier and emit more CO2 equivalents than soil masses that are transported by a dumper truck inside the project area for reuse purposes. The analysis indicates that an increased maximum load in combination with a shorter distance is the most cost-efficient option. The study also highlights the importance of including the entire value chain (client-consultant-contractor) as well as updating the industry's otherwise conservative approach to mass management.

In countries with harsh winter climates extensive winter road maintenance is necessary to achieve traffic accessibility and road safety. These measures have high economic and environmental costs as snow free roads and winter road maintenance in Sweden today is achieved by a combination of mechanical snow clearance and the spreading of salt to prevent ice formation. The salt ends up in the roadside environment and has negative effects on groundwater and vegetation. An alternative to traditional winter road maintenance to obtain non-skid winter roads is the use of hydronic pavement(HP) systems. Existing HP systems in Sweden are powered by district heating which limits the application to urban locations. The goal is to utilize renewable energy sources such as geoenergy which can be used in both rural and urban locations. This thesis suggests Hamnbacken in Visby as a pilot project for a full-scale application of the proposed HP system using surface water source heat.The weather related road surface conditions on Hamnbacken, and the potential of a renewable energysource have been examined in this study and the proposed location has been found favourable for a HP system. / Länder med övervägande kallt vinterklimat är halkbekämpning en nödvändighet för trafikens framkomlighet och säkerhet. Åtgärderna som vidtas för att få snö- och isfria vägar är kostsamma samt har en hög miljöpåverkan, ett vedertagligt exempel är plogning och saltning. Saltet hamnar i slutändan inom vägens omgivande områden och har en negativ påverkan på grundvatten och vegetation. En alternativ lösning till traditionell halkbekämpning är uppvärmda vägar för att uppnå ett halkfritt vinterväglag. Befintliga väguppvärmningssystem i Sverige försörjs av fjärrvärme vilket är en begräsning då tillgången till fjärrvärme finns i anslutning till tätorter. Målet är att utnyttja förnybara energikällor såsom geoenergi som är tillgänglig både i tätorter och på landsbygden. Det här examensarbetet undersöker Hamnbacken i Visby som ett pilotprojekt för en fullskalig implementering av väguppvärmningssystem där sjövärme används som energikälla. Denna studie har undersökt väderrelaterade vägförhållanden på Hamnbacken samt potentialen för användning av sjövärme. Den föreslagna platsens förutsättningar har visat sig vara gynnsamma i detta avseende.