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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Výzkumně-vzdělávací centrum nanotechnologie (NanoArch) / Nanotechnology educational and research center (NanoArch)

Hamdanieh, Livine Unknown Date (has links)
„Science, the Never-Ending Quest.“ The diploma thesis deals with a proposal of science center aimed at promoting science and education in the field of nanotechnology. The aim of the project is to design a science center that will complement the existing building complex of CEITEC Nano BUT but also through its architectural expression represent the value of such institution and enable it to stand out among the existing buildings, allowing it to become the new center „brain“ of the complex. Nanotechnology represents a significant sphere of the scientific world that holds big potential for the future in various industries including architecture and building construction. The aim of the diploma thesis is thus not only to design new science center but also to raise awarness of nanotechnolgy. The design proposal is based on simple geometric shape - circle which is segmented into three parts. Logical shape of circle complements the already existing complex and becomes the new center point "brain" of the whole complex. The symbol of infinity that circle and Mobius strip represent is associated with the never ending scientific research as the science itself is at the end nothing but a "never ending quest".
302

Alterungsverhalten von polymeren Zwischenschichtmaterialien im Bauwesen: Ageing Behaviour of Polymeric Interlayer Materials in Civil Engineering

Kothe, Michael 03 December 2013 (has links)
Verbund- und Verbundsicherheitsgläser zeichnen sich durch ein breites Anwendungsspektrum im Bauwesen, im Automobilbau und der Photovoltaikindustrie aus. Dabei werden insbesondere an Verbundsicherheitsglas hohe Anforderungen hinsichtlich der Sicherheitseigenschaften gestellt. Diese Eigenschaften, wie Splitterbindung und Resttragfähigkeit, werden durch einen Verbund aus mindestens zwei Glasscheiben mit einem polymeren Zwischenschichtmaterial realisiert. Aktuell werden in etwa 95% aller Fälle Zwischenschichten aus Polyvinylbutyral für die Herstellung von Verbundsicherheitsglas eingesetzt, da einzig dieses Material bauaufsichtlich geregelt ist. Dabei sind aber auch verschiedene andere Materialien, wie Ethylen-Vinylacetat, thermoplastische Polyurethane oder Ionomere als Zwischenschichten einsetzbar. Aufgrund ihrer Eigenschaften erweisen sich diese für spezielle Anwendungsgebiete als besonders geeignet. Gegenstand dieser Arbeit ist die Untersuchung verschiedener polymerer Zwischenschichtmaterialien hinsichtlich ihrer Eignung für die Herstellung von Verbund- und Verbundsicherheitsgläsern, speziell im Vergleich zur Polyvinylbutyral-Folie. Dabei wird ein besonderes Augenmerk auf das Alterungsverhalten der Zwischenschichten gelegt, um deren Eignung auch für mehrere Jahrzehnte Standzeit, wie sie für Bauwerke zu erwarten ist, einschätzen zu können. Um das Alterungsverhalten der verschiedenen polymeren Zwischenschichtmaterialien beurteilen zu können, werden zunächst die Materialeigenschaften der verschiedenen Zwischenschichten im ungealterten Zustand an reinen Substanzprüfkörpern beziehungsweise ungealterten Verbundgläsern ermittelt. Als Alterungsszenarien werden eine Temperaturlagerung, eine Beanspruchung durch wechselnde klimatische Bedingungen, sowie eine Lagerung unter aggressiven Medien und eine Bestrahlungsprüfung zur Beurteilung der Langzeitstabilität durchgeführt. Die verschiedenen Alterungstests mit kleinformatigen Verbundglas-Prüfkörpern wirken sich dabei sowohl auf das optische Erscheinungsbild der Verbundgläser, als auch auf die Materialeigenschaften aus. Neben der Bildung von Blasen, Delaminationen oder Trübungen, führen diese Tests durch chemische Reaktionen oder physikalische Umlagerungen zur Veränderung des Steifigkeits- und Abbauverhaltens der polymeren Zwischenschichtmaterialien. Auf Grundlage der Ergebnisse der in dieser Arbeit durchgeführten Alterungstests erscheinen das untersuchte Ionomer (DuPont SentryGlas) und ein thermoplastisches Polyurethan (Huntsman Krystalflex PE399) am besten für einen dauerhaften Einsatz als Zwischenschichtmaterial für Verbund- und Verbundsicherheitsgläser als geeignet. Durch eine Anpassung der Einbausituation oder eine Beschränkung der Einsatzgebiete und der damit einhergehenden klimatischen Beanspruchungen können auch die anderen Materialien vorteilhaft eingesetzt werden. / Laminated glass and laminated safety glass are used in a wide range of applications, for example in construction, automotive and photovoltaic industry. High demands on security properties are made, especially to laminated safety glass. These properties, such as binding glass fragments in case of breakage and the residual bearing capacity, will be realized by a composite of at least two panes of glass with a polymeric interlayer material. Currently, in about 95% of all cases, interlayer of polyvinyl butyral are used for the production of laminated safety glass, because this is the only material, which is approved by the building authorities. Various other polymeric materials such as ethylene vinyl acetate, ionomers and thermoplastic polyurethanes can also be used as interlayers. Based on their properties, these materials are suitable for special applications. Subject of this thesis is the study of various polymeric interlayer materials in reference to their suitability for the production of laminated glass and laminated safety glass, especially in comparison to the polyvinyl butyral interlayer. Especially the ageing behaviour of the interlayer is investigated to estimate their suitability over the lifetime of several decades, which is expected for building structures. To evaluate the ageing behaviour, the material properties of the different polymeric interlayer materials are first determined on the pure, unaged material or unaged laminates. Different ageing scenarios are carried out to assess the longterm stability, such as a temperature storage test, a climatic stress test as well as test under aggressive media and high irradiation. These ageing tests with small-scale test specimens will affect both the appearance of the laminated glass, as well as the material properties. In addition to the formation of bubbles, delamination or haze, these tests lead to changes in stiffness and degradation behaviour of the polymeric interlayer materials by chemical reactions or physical rearrangements. Based on the results of the ageing tests in this thesis, the investigated ionomer (DuPont SentryGlas) and a thermoplastic polyurethane (Huntsman Krystalflex PE399) are best suited for a long-term use as interlayer material for laminated glass or laminated safety glass. By changing the structural design or limiting the range of applications, the other investigated materials can also show their advantages for different applications.
303

Underlag för projektering av sockelkonstruktioner : En kvalitativ analys av sockelkonstruktionen utifrån kriterierna funktion, byggbarhet, beständighet och utformning / A Guide for Base Construction : A Qualitative Analysis of the Connection Between Outer Wall and Ground Plate

Gustafson, Anna, Krogh, Jenny January 2019 (has links)
Sockelkonstruktionen är en del av grundkonstruktionen i en byggnad där yttervägg möter mark. Den är en utsatt del av en byggnads klimatskärm och exponeras både för det svenska klimatet och markfukt. Projektering av en sockelkonstruktion är tidskrävande och kräver stor kunskap inom flera områden för att uppnå de krav som ställs. Syftet med denna rapport är att underlätta och förbättra projekteringen av sockelkonstruktioner hos uppdragsgivande byggkonstruktionsföretaget Kåver & Mellin. För att uppfylla syftet är målet att rapporten ska fungera som ett vägledande underlag som kan användas vid projektering av sockelkonstruktioner. Underlaget ska utgå från kriterierna funktion, beständighet, byggbarhet och utformning. Genom en litteraturstudie i kombination med kvalitativ datainsamling och kvalitativa intervjuer med sakkunniga i byggbranschen framställdes resultatet. Detta har legat till grund för analys och slutsats. Resultatet visar att det finns många sätt att utforma en sockelkonstruktion för att uppnå det krav som ställs. Viktiga faktorer vid utformning av sockelkonstruktioner är byggprojektets förutsättningar och de i sockelkonstruktionen ingående delarnas möten och material. Mer ingående rekommendationer återfinns i rapporten under slutsatser. Resultatet indikerade också att det inte finns tydliga regler för hur sockelkonstruktioner ska utföras. Olika regelverk tolkas olika vilket visar på ett behov av att informationen tydliggörs. Denna rapport kan ses som ett vägledande underlag att använda vid projektering av sockelkonstruktioner. / The base of the construction where the outer wall is connected to the ground plate is the connection dealt with in this report. We refer to it as the base. The base leads the loads from the building down to the ground and is supposed to protect the building from outer impact. This part of the building shell is well exposed with the Swedish climate and in constant contact with wet ground. Forming a base is difficult in many ways and demands knowledge in many different areas. It takes a great amount of time and it is hard to be sure that you fulfill the specific demand of each construction in each project. The aim of this report is to make the process of forming a base easier and better for the sponsoring company Kåver & Mellin. The report is supposed to lead to a written report that could be used as a guide when forming bases. The report is based on the four criterias: function, constructability, constancy and shaping. The result came from studying literature, interviewing experts in the branch of building construction combined with sorting drawings of bases from former projects at Kåver & Mellin. The result has been analyzed and lead to several wide and narrow conclusions about bases. The result showed that there are many ways of forming a base to reach the demand of each project. Aspects to think about when forming a base is the demands of each project and the materials and connections in the base. The result also showed that there are no clear directions of how to form a base in a building. Different laws and rules can be read in different ways depending on who is reading which shows that the guidelines could be clearer. This report is a guide of how to think when forming a base in a building.
304

UTILIZING T-O-E FRAMEWORK FOR EVALUATING THE USE OF SIMULATORS IN SNOWPLOW DRIVER TRAINING

Yanchao Zheng (14277284) 20 December 2022 (has links)
<p>  </p> <p>Driving simulators have been introduced by some American states’ department of transportation (DOT) as a supplementary tool to train their snowplow drivers. This is a costly investment that requires careful planning. Yet, there is a current lack of recent studies that holistically evaluate factors affecting the decision-making process on adopting the driving simulator in winter snowplow driver training. The current research aims to fill this gap by employing the theoretical framework of Technology-Organization-Environment (T-O-E) to explore factors affecting state DOTs’ decision-making process of adopting snowplow driving simulator in driver training. Relevant factors were identified first using a scoping review of literature, and then validated by interviews with DOT stakeholders. Subsequent findings from the state DOT survey suggests that perceived long-term effect on public safety, cost related to simulator training, and ease of the relocation of simulator are the top contributors when it comes to the factors affecting decision-making on adoption of snowplow driving simulator in training. The resulted T-O-E framework contains 11 factors cross-verified from various sources, in which most factors such as simulator fidelity and relative advantage were categorized to technology context under the T-O-E framework, while the main environment factor relates to normative and mimetic pressure. The paper contributes to academic research by applying T-O-E to offer decision making support for using simulator technology for training of snowplow drivers; and to practitioners by providing state DOT decision makers a framework to analyze different factors on adopting snowplow driving simulators in training.</p>
305

KLIMATPÅVERKAN FRÅN EN HEL STADSDEL : Var kan optimeringar göras? / CLIMATE IMPACT FROM AN ENTIRE DISTRICT : Where can optimizations be made?

Hökfors, Johannes January 2022 (has links)
I dagens samhälle är klimatfrågan central och dess betydelse ökar ständigt. Byggbranschen står för ungefär en femtedel av utsläppen i Sverige när det gäller koldioxidekvivalenter. För att minska dessa har krav på klimatdeklarationer för byggnader införts och dessa kommer kompletteras med gränsvärden som börjar gälla senast 2027. Utsläpp från infrastruktur finns det inte samma krav på och utsläpp från hela stadsdelar är relativt outforskat. Syftet med denna rapport är därför att skapa ett helhetsperspektiv genom att undersöka klimatpåverkan från en hel stadsdel med alla byggnader och infrastruktur. Uträkningar utförs med programmen Carbon designer och Klimatkalkyl för byggnader respektive infrastruktur. Från uträkningar kan sedan de största bidragarna till klimatpåverkan identifieras. Utifrån litteratur kan optimeringar för minskning av klimatpåverkan tas fram och deras inverkan på det totala utsläppet bestämmas. Resultatet indikerar att infrastrukturen står för cirka 2 % av utsläppen för området Kronan i Luleå där byggnader står för övriga procent. Undersökning av optimeringar visar att minskningar kan uppnås genom byte till grön asfalt, träbyggnader och HVO-diesel. För transport är det lämpligt att använda närproducerade material i trä för minskning av utsläpp. I övrigt indikerar undersökning av utformning att byggnader med över 6000 m2 ger minst klimatpåverkan. Byggnaden ska bestå av trä och göras i 6 till 8 våningar för att ytterligare minska klimatpåverkan. Det kan även vara fördelaktigt att fokusera på radhus då dessa har en lägre klimatpåverkan. Undersökningen gällande radhus bygger dock på många antaganden och behöver utvecklas för att säkerställa resultatet. Slutligen kan det konstateras att det är viktigt att se till helheten när det gäller klimatpåverkan. Kommuner har i sina detalj- och översiktsplaner möjlighet att beakta ett helt område och kan på så sätt minska klimatpåverkan med helhetsperspektivet. Dessa kan styra över utformningen till viss del med våningsantal och storlek på byggnader och på så sätt arbeta för ett lägre klimatpåverkande utsläpp för hela stadsdelen. Upphandlingen är även ett lämpligt tillfälle för att ställa krav på klimatpåverkan och premiera alternativ med lägre utsläpp. / In today’s community the climate issue is central, and its importance is constantly increasing. The construction industry accounts for approximately one fifth of emissions in terms of carbon dioxide equivalents. To reduce these, climate declarations for buildings have been introduced and these will be supplemented with limit values ​​that will come into effect no later than 2027. Emissions from infrastructure do not have the same requirements and emissions from entire city districts are unexplored. The purpose of this report is therefore to create an overall perspective by examining the climate impact of an entire city district with all buildings and infrastructure. Calculations are made using the software Carbon designer and Klimatkalkyl for buildings and infrastructure, respectively. From calculations, the biggest contributors to climate impact can then be identified. Based on literature, optimizations for reducing the climate impact can be developed and their impact on the total emission determined. The result indicates that the infrastructure accounts for approximately 2 % of the emissions for the area Kronan in Luleå, with buildings accounting for the remaining percentages. Investigation of optimizations shows that reductions can be achieved by switching to green asphalt, wooden buildings and HVO diesel. For transport, it is appropriate to use materials made with wood that are locally produced to reduce emissions. Examination of the design indicates that a wooden house that is between 6 and 8 storeys with a gross floor area of at least 6000 m2 is optimal for building with as little climate impact as possible. It can also be beneficial to focus on terraced houses as these have a lower climate impact. However, the survey regarding terraced houses is based on assumptions and needs to be developed to ensure the result. Finally, the overall perspective is important. Municipalities have in their detailed and overview plans the possibility to consider an entire district and can thus reduce the climate impact with the overall perspective. They can control the design to a certain extent with the number of floors and size of buildings and in this way work for a decreased carbon dioxide emissions for the entire district. The procurement is also a suitable opportunity to set demands on climate impact and reward alternatives with lower emissions.
306

Комплексное технико-экономическое обоснование применения строительных машин при возведении монолитного остова гражданского здания : магистерская диссертация / Comprehensive feasibility study of the use of construction machines in the construction of a monolithic skeleton of a civil building

Файзерахманов, А. Р., Faizerakhmanov, A. R. January 2021 (has links)
В работе представлено комплексное технико-экономическое сравнение строительных машин, применяемых при возведении монолитного железобетонного остова гражданских зданий по различным критериям, для обеспечения эффективности строительства. / The paper presents a comprehensive technical and economic comparison of construction machines used in the construction of a monolithic reinforced concrete skeleton of civil buildings according to various criteria to ensure the efficiency of construction.
307

Оценка достоверности строительной исполнительной документации на примере исполнительных геодезических схем : магистерская диссертация / Assessment of the reliability of construction as-built documentation on the example of as-built geodetic schemes

Орлова, Е. А., Orlova, E. A. January 2022 (has links)
Разработан способ и программа для оценки исполнительных геодезических схем в камеральных условиях с целью обоснования принятия решения о необходимости проведения инструментального контроля планово-высотного положения строительных конструкций. / A method and program have been developed for evaluating executive geodetic schemes in office conditions in order to justify the decision on the need for instrumental control of the planned-altitude position of building structures.
308

<b>Enhancing Highway Safety and Construction Quality Control Through Friction-Based Approaches</b>

Jieyi Bao (19180027) 19 July 2024 (has links)
<p dir="ltr">Pavement friction is fundamental to the safety of road networks. A precise assessment of friction levels is essential for the strategic development of maintenance practices and policies by state highway agencies. Typically, assessments of pavement friction have been conducted individually, focusing on particular segments of roadways. Nevertheless, this approach does not offer a thorough evaluation of roadway friction conditions at the network level. This study combines the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) and the Gaussian Mixture Model (GMM) to evaluate the ratings of pavement friction throughout the entire state’s road system. A dataset oriented towards safety, serving as input for clustering models across various data dimensions, has been established. Through comparative and statistical analyses, six friction performance ratings have been identified and subsequently validated. The findings not only facilitate a deeper comprehension of the interrelations among friction levels, crash impact, and additional factors impacting safety, but also provide substantial insights for the advancement of road safety, management, and development.</p><p dir="ltr">Pavement markings play an essential role in regulating traffic flow and improving traffic safety. Beyond facilitating road safety via visual cues to drivers, the frictional properties of pavement marking surfaces are a pivotal element in safeguarding roadway safety. However, the friction characteristics of pavement marking surfaces have not been sufficiently investigated. Additionally, the integration of glass beads or other particles with pavement markings to enhance reflectivity and retroreflectivity complicates the study of their friction properties compared to bare pavements. To tackle these problems, this research utilizes the British pendulum tester (BPT), the circular track meter (CTM), the dynamic friction tester (DFT), and the three-wheel polishing device (TWPD) to evaluate the friction performance of various pavement markings. Eighteen specimen groups, comprising six types of markings (i.e., waterborne paint, preformed tape, epoxy paint, polyurea paint, MMA paint, and thermoplastics) with various glass beads and particles, were investigated to assess their impact on dry and wet friction, mean profile depth (MPD), and durability. The outcomes of this study serve as valuable resources for advancing safety measures and providing insights into emerging traffic management technologies.</p><p dir="ltr">Currently, there is an absence of established standards or methods for assessing and evaluating the friction characteristics of road markings. This lack of standardization has a pronounced impact on vulnerable road users-motorcyclists, bicyclists, and pedestrians-due to the potential for inadequate friction from road markings. To address the problem, this study has developed five friction levels based on the wet British pendulum number (BPN). Leveraging international standards and practical considerations, a tentative BPN range is advocated for crosswalks, symbols, and letters to enhance the safety of pedestrians and other susceptible road users.</p><p dir="ltr">Friction metrics, like MPD and friction number (FN), have been central to enhancing quality assurance and control (QA/QC) processes in chip seals. These metrics evaluate chip seal performance by examining problems such as aggregate shedding or significant bleeding, potentially leading to lower friction values or surface textures. However, instead of leading to slippery conditions, the loss of aggregate-particularly as a consequence of snow-plow operations-may result in the formation of uneven surface textures. The relationship between increased MPD or FN and enhanced chip seal quality is complex and not easily defined. This study introduces a groundbreaking method utilizing machine learning techniques, designed to improve the QC procedure for chip seals. A hybrid anomaly detection approach was applied to a dataset consisting of 183,794 MPD measurements, each representing the average mean segment depth (MSD) over 20-meter segments, gathered from real-world chip seal projects throughout the six districts managed by INDOT. A two-phase QC process, specifically tailored for chip seal quality assessment, has been developed. Validation analysis performed on four chip seal projects shows a strong concordance between field inspection, friction measurements, and the results predicted using the introduced approach. The developed method sets a foundational chip seal QC procedure, augmenting efficiency in acceptance processes and overall safety through data-driven techniques, while reducing the practitioners' time on site.</p><p dir="ltr">Surpassing the constraints of traditional approaches, this paper develops a series of scientific methodologies for evaluating friction on pavement and pavement marking surfaces through extensive in-field and laboratory experiments. Additionally, it establishes rational and efficient quality control procedures for chip-seal applications. The methodologies and conclusions presented in this paper can assist engineers in Departments of Transportation (DOTs) with ensuring the safety of all stakeholders, including road users, engineers, and construction practitioners. Furthermore, they offer valuable insights for the timely execution of road maintenance activities.</p>
309

Träavfallshantering vid nyproduktion av byggnader : Åtgärdsförslag för att minska mängden träavfall och öka återbruk av träprodukter vid nyproduktion

Cordts, Linda, Nordlund, Isabel January 2024 (has links)
I takt med att medeltemperaturen på jorden ökar och allt fler krav ställs på företag gällande hållbarhetsarbete behöver konsumtionen minska. Bygg- och anläggningssektorn står för 20 procent av Sveriges växthusutsläpp och genererar 14,2 miljoner ton avfall varje år, där större delen av avfallet är dåligt sorterat och ibland funktionsdugligt. Ökandet av återbruk och återvinning skulle medföra både miljömässiga och ekonomiska nyttoeffekter. Detta examensarbete genomfördes tillsammans med Einar Mattsson Byggnads AB där syftet var att undersöka avfallshanteringen, problematiken som finns och hur den går att förbättra för att minska mängden träavfall att gå till energiåtervinning. Studien har innefattat intervjuer med logistikansvariga, träleverantörer, hantverkare och arbetsledare för att bilda en uppfattning om nuvarande avfallshantering och möjligheten till återbruk eller alternativa lösningar. Detta har kompletterats med en enkät och observationer från ett nyproduktionsprojekt där träavfallet har identifierats och volymuppskattats. Kombinationen av använda metoder fastställde engångspall som största fraktion i träavfallet och att mycket avfall bestod av spill från träfiberskivor och konstruktionsvirke. Det framgår att det finns en positiv inställning till återbruk och att ökad plats och kommunikation i stort hade minskat avfallsmängden. Träavfall som inte går att undvika kan i stället gå till produktion av träfiberskivor. En branschgemensam förändring hade kunnat bidra till en omställning men att det för ett enskilt företag kan vara svårt. För att minska mängden lastpall i avfallet ses införande av retursystem som en lönsam och hållbar åtgärd. / Due to the increasing average temperature of the earth and the increase in requirements the consumption must decrease. The construction industry in Sweden currently accounts for 20 per cent of the green house emission and generates 14,2 million tons of waste each year. An increased reuse and recycling would bring both environmental and economic benefits. The thesis is produced in collaboration with Einar Mattsson AB with the purpose to investigate the possibilities to decrease the amount of wood waste in new construction building and to present a recommendation of solutions. To do that, the study has included interviews with logistic managers, wood suppliers, craftsmen, and supervisors which made it possible to estimate current waste management and the possibility of reuse or alternative solutions. The interviews were supplemented with questionnaires and observations form a new construction project, where the volume of wood waste was identified and estimated. This resulted in the largest fraction being disposable pallets and waste of material. Furthermore, the suggested solutions to decrease the waste of wood are believed to be increased communication between all actors involved and greater space of storage may lead to an improved waste management. Also, a change in working methods and agreements with suppliers is required. Wood waste that still occurs should be used in manufacturing of wooden fiberboards used in building production.
310

Leveraging Lessons from Earth to Space: Failure Analysis Framework Based on the Notion of "Embedded Pathogens” for Designing and Building Safe Extraterrestrial Systems

Takaharu Igarashi (19734085) 25 September 2024 (has links)
<p dir="ltr">The deep human drive to explore and inhabit new frontiers underpins the emerging field of space architecture, as evidenced by the proliferation of diverse design concepts and growing momentum in extraterrestrial construction. However, the endeavor of building off-world environments remains in its infancy, facing numerous challenges due to remoteness, novelty, complexity, and other inherent characteristics. Significant technical and methodological gaps exist between visionary designs and the practical engineering and management intricacies of complex projects. These gaps must be addressed to overcome the challenges in extraterrestrial construction.</p><p dir="ltr">The field is limited by the scarcity of both failures and successes in extraterrestrial construction from which to draw lessons. Furthermore, the understanding of construction system failures is constrained by the limited application of systems perspectives in construction safety literature. Existing accident causation models in system safety literature are ill-suited for describing construction system failures.</p><p dir="ltr">The overall objective of this research is to inform the planning and design of extraterrestrial construction to mitigate the risk of building and installing defective systems in space. To achieve this goal, the research process followed iterative cycles of failure case studies, extracting insights through the lens of a new accident causation model. The cycles of model application evolved through three major stages: (1) developing a model specifically tailored to construction system failures, (2) deriving concepts and principles for interpreting the model depictions, and (3) compiling lessons from a systematically selected set of failure cases for planners, designers, and key stakeholders of future extraterrestrial construction projects.</p><p dir="ltr">Following a comprehensive literature review, this study developed an accident model termed the framed-and-layered accident pathogen propagation (FLAPP) model. The basic concept of the model consists of frames representing the temporal dimension, layers depicting the hierarchical aspects of the sociotechnical framework of construction projects, and graphical notation illustrating the sequence of defective processes and pathogens embedded in the constructed artifact.</p><p dir="ltr">To interpret the graphical illustrations of failure cases, the study introduced the concept of pathogen threads to describe multiple sequences of defective processes ultimately interacting with the physical artifact. To further explain the underlying mechanisms of how design decisions incubate into system failures, the concept of design-induced strains was proposed. This concept represents the lingering effects that design solutions can have on physical artifacts and downstream organizational processes. Additionally, categories of inadequate organizational factors from the Human Factors Analysis and Classification System (HFACS) were incorporated to explain the underlying causes within project organizations that allowed the mishandling of physical and organizational strains.</p><p dir="ltr">To evaluate the applicability of the FLAPP model and observe general trends in system failures across various contexts, the study selected failure cases attributable to embedded pathogens with sufficient available information. Ensuring that the case set included diverse cases and covered all specific technical challenges of extraterrestrial construction, the selection resulted in a set of 40 cases comprising 10 space systems, 13 buildings, 10 bridges and tunnels, and 7 systems in specialized environments. Results highlighted typical and exceptional cases among different systems and the general trends of occurrence prevalence of concept instances among different system contexts (space, building, bridge/tunnel, specialized environment) and duration ranges (short, medium, long). The comparison of Earth-based and space-based systems revealed several critical questions for the space domain: how to ensure, maintain, and improve the reliability and quality of unique and site-specific systems; how to establish and enforce minimum quality standards to reduce unintended physical strains; and how to prepare for extended project timelines with dynamic and transient organizational networks.</p><p dir="ltr">Future research should address the theoretical and methodological limitations of the FLAPP model by extending it to investigation methods and risk assessment techniques. Additionally, the failure case study approach should be enhanced by expanding the case set, exploring source documents, and applying additional analysis approaches. This dissertation concludes by demonstrating that guidance and principles with discipline-specific vocabulary can be derived by referencing documented best practices in systems engineering and project management.</p><p><br></p>

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