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Raumplanerische Ansätze zum Siedlungsflächenmanagement in Metropolregionen. Ein Vergleich von Ansätzen in den USA, Kanada und Deutschland
Get PDFMany metropolitan regions face concerns over sprawling development, increased costs of maintaining infrastructure, and loss of green space and farmland. Some metropolitan regions have intentionally created spatial policies to govern development patterns and manage growth within their region. This paper compares the spatial policies applied in three case studies: the Puget Sound region (Washington State, USA), Metro Vancouver region (British Columbia, Canada) and Stuttgart region (Baden-Württemberg, Germany). While all three regions share a vision that can broadly be summarised as transit-connected communities, each metropolitan planning organisation leverages a variety of spatial policies. Based on the unique planning cultures, various governmental actors take on different roles at the local, county, regional and state levels. This paper categorises and compares the multi-level responsibilities for defining, mapping, and implementing spatial policies. With this focus, the paper provides an international comparative perspective on approaches, context, and contents of multi-level growth management
Integrating Visualization and Interaction Tools for Enhancing Collaboration in Different Public Participation Settings
Get PDFThe demand for participant engagement in urban planning shows a great need for tools that enable communication between stakeholders and make planning processes more transparent. So far, common methods use different tools and platforms independently. This prevents the full potential for effective, efficient, and creative collaboration from being realized. Hence, this paper presents an approach that combines different participation settings (off-site, on-site, and online) by using an interactive touch table and an additional screen, as well as virtual reality (VR) and augmented reality (AR) devices, and synchronizing them in real-time. To fulfill the collaboration requirements, three major technical aspects are addressed in the concept and prototype implementation: Firstly, the demands for various settings and devices require a uniform and cross-device interaction concept. Secondly, all changes in the course of the participation (e.g., adding, manipulating, or removing objects) must be synchronized across all devices in real-time, with very low latency. Thirdly, the various states should be saved persistently during the collaboration process. Detailed empirical usability studies are still pending; however, pretests indicate that the concept is appreciated, and the transferability to other planning processes is given
A Circular Economy Approach to Multifunctional Sandwich Structures: Polymeric Foams for District Heating Pre-Insulated Pipes
Get PDFDistrict heating pre-insulated pipes are a sandwich structure of material layers. Polyurethane foam bonds the medium pipe with the casing, providing an insulating function as well as a load bearing function. The high toxicity of the di-isocyanates required for its manufacturing triggers the need for a replacement. In this work, alternatives have been researched and developed considering the requirements of the circular economy. Two technology readiness levels (TRL) were covered. The higher TRL involved the evaluation of commercially available polymeric foam alternatives. Polyethene terephthalate foam was selected, and its ageing behaviour concerning degradation sources inherent to the application was studied in detail to confirm the fulfilment of the required service life. No degradation of the mechanical properties was found after exposure to thermal cycles or hygrothermal conditions at temperatures below its glass transition, which would correspond to the scenario of groundwater ingress. The previously determined highest service temperature of 80ºC was found conservative, as annealing at 100ºC increases its strength, allowing this service temperature. All results suggest it is a suitable candidate for the insulation of steel medium pipes. The fast embrittlement upon exposure to hot moisture, as would occur due to permeation of the heat carrier through a plastic pipe, prevents its recommendation for this case.The lower TRL research involved the re-evaluation of the complete sandwich assembly, from a cradle-to-cradle perspective. The foamability of polybutene-1 was explored, with the ultimate target of allowing the manufacturing of the sandwich element out of a single material, as to facilitate its recycling. Favourable grades for foaming were identified, confirming its foamability. The relationships between process parameters and the foam’s microstructure were evaluated. Foams in the required size for mechanical and insulating properties characterization were successfully produced. Mechanical properties of PU from state-of-the-art flexible plastic medium pipes fall in the prediction bands obtained from the produced PB-1 foams. This provides confidence on the suitability for the application.Vorgedämmte Fernwärmerohre bestehen aus mehreren Schichten unterschiedlicher Materialien. Im Standardfall verbindet ein Polyurethanschaum das Mediumrohr aus Stahl mit der Ummantelung aus Polyethylen. Der Schaum hat die Funktion der Wärmedämmung und ist für den kraftschlüssigen Verbund zwischen den Schichten zuständig. Durch die hohe Toxizität der für die Herstellung von Polyurethan erforderlichen Di-Isocyanate ist die Nachhaltigkeit des Polyurethanschaumes in Frage gestellt und es ist zukünftig wahrscheinlich ein Ersatz erforderlich. In dieser Arbeit wurde unter Berücksichtigung der Anforderungen der Kreislaufwirtschaft untersucht, welche Alternativen möglich sind. Es wurden dabei zwei unterschiedliche Stufen des technologischen Reifegrades (engl. TRL=Technology Readiness Level) abgedeckt. Auf dem höheren Reifegrad wurden kommerziell verfügbare polymere Schaumstoffalternativen bewertet. Ausgewählt wurde der Polyethylenterephthalat-Schaumstoff, dessen Alterungsverhalten im Hinblick auf anwendungsspezifische Degradationsquellen eingehend untersucht wurde. Dabei wurde keine Verschlechterung der mechanischen Eigenschaften festgestellt, nachdem der Schaum thermischen Zyklen oder hygrothermischen Lastkollektiven bei Temperaturen unterhalb des Glasübergangs ausgesetzt war. Die in der Literatur verbreitete maximale Betriebstemperatur von 80 ºC erwies sich als konservativ. Es wurde festgestellt, dass durch das Glühen des Materials im Betrieb die Festigkeit erhöht wird, wodurch eine Betriebstemperatur von 100°C ermöglicht wird. Alle Ergebnisse deuten darauf hin, dass Polyethylenterephthalat ein geeigneter Kandidat für die Dämmung von Stahlmediumrohren ist. Bei Kunststoffmediumrohren ist infolge von Dampfdiffusion in die Dämmung eine schnelle Versprödung bei Einwirkung von heißer Feuchtigkeit zu erwarten. Daher kann Polyethylenterephthalat für die Dämmung von Kunststoffrohren nicht empfohlen werden.Auf dem niedrigeren Reifegrad wurde der gesamte mehrschichtige Aufbau von Rohrleitungen für den Wärmetransport unter dem cradle-to-cradle Prinzip neu bewertet. Die Schaumherstellung von recyclebaren Polybuten-1 wurde mit dem Ziel untersucht, eine vorgedämmte Rohrleitung für den Wärmetransport aus einem einzigen Material zu ermöglichen, um Schwierigkeiten der Materialtrennung für einen geschlossenen Materialkreislauf zu umgehen. Insbesondere wurde der Druckabfall, welcher den größten Einfluss auf die Mikrostruktur des Schaums hatte, im Herstellungsprozess eingehend untersucht. Letztlich wurden Schäume hergestellt, die alle technischen Anforderungen für den Einsatz beim leitungsgebundenen Wärmetransport erfüllten. Insbesondere liegen die mechanischen Eigenschaften der Polybuten-1-Schäume in der Größenordnung des bisher üblichen Polyurethan-Schaumes für flexible Wärmerohre
Towards productive and socio-natural urban landscapes : tapping urban agriculture’s potential as a tool for sustainable development
Get PDFWorldwide, the percentage of people living in urban areas will increase from 50% in 2010 to nearly 70% by 2050. While in many parts of the world, human development is expanding rapidly on the urban fringe and at the expense of rural hinterlands, some cities decided to focus on densifying the built environment.
Since densification leads to a quantitative reduction of open spaces, the pressure on the remaining ones is significantly increasing. On the one hand, open spaces should meet the requirements of its users, on the other hand, they have to fulfil expectations regarding climate adaptation and operating efficiency. Thus, to satisfy these claims, urban open spaces have to be endowed with multi-functionality.
Urban agriculture, in turn, offers indispensable opportunities to solve - or at least deal with - urban challenges regarding sustainability, health, economy, society, urban design and local food supply. Due to its cross-cutting and multi-dimensional nature, it has the potential to meet a good many of requirements on open spaces. Nonetheless, it still inherits a rather low visibility on the agenda of urban planners.
This situation could stem from various reasons, whereby a gap in the understanding of urban agriculture’s capability seems to be a major cause. To this day, there exists no comprehensive literature on the subject - neither a holistic view on urban agriculture’s multifaceted benefits nor its impacts on urban open spaces. Thus, the purpose of this study is to tap urban agriculture’s potential and to emphasise its raison d’être in sustainable urban planning
Ein digitaler Zwilling für die Versuchseinrichtung "District LAB" : Hintergrund, Ideen und aktuelle Aktivitäten : Ein Überblick
Get PDFDistrict heating systems are an important element for the success of the heat transition and the associated and necessary decarbonisation of the urban heat supply. Although the expansion and transformation of district heating grids towards decentralised supply solutions based on renewable energies or waste heat is accompanied by some advantages, there are also obstacles, especially economic ones. Digitalisation measures appear to be a promising way of counteracting these. The aim of the doctoral thesis presented in this paper is to develop a solution and to test these empirically at the experimental facility “District LAB”. The methods planned to achieve these goals are primarily the creation of a simulation model that contains all the essential thermo-hydraulic components and control structures of the test facility, as well as the transfer of this model into a digital twin that has access to its hardware. Furthermore, a solution regarding the predictive optimisation of the operation strategy is to be developed and subsequently tested. In the following, the planned methods and work steps are presented in detail and the first results of theoretical investigations are shown.Bundesministerium für Wirtschaft und Energi
An Analysis of the most Frequent Operational Temperature of four District Heating Networks of Germany
Get PDFPre-insulated pipes according to EN 253:2019 that are used in District Heating (DH) networks comprise of minimum three layers. These layers are steel medium pipe, rigid polyurethane (PUR) foam as the insulation layer, and a polyethylene (PE) casing as the protection layer. Various studies show that the thermo-oxidation of the PUR foam is one of the most critical mechanism that determines the service-life of the pre-insulated bonded pipe systems. The deterministic approaches for service-life estimation considers the design temperature of the network e.g. 120°C, however the DH operational flow temperature is not constant. In recent decade, due to the decarbonisation trends and new artificial intelligent (AI) based techniques, the DH networks are optimized better than before and therefore, the DH operating flow temperature reduced to some extent. This temperature reduction affects the thermo-oxidation reaction speed, and the thermo-oxidation level of the PUR foam is very crucial to understand the adhesion of the PUR foam at the interface of the steel pipe and accordingly the service-life prediction of the pipe. Moreover, it affects the axial shear strength, which is necessary to impede the steel pipe movement that is caused by thermal expansion and to reduce the mechanical cyclic load. In this paper, the temperature changes of four different DH networks in Germany are analysed and the aim is to reveal the flow temperature of the in-operation DH pipes, Equivalent to Constant Continues Temperature (ECCT). The ECCT would be useful for different purposes such as thermo-oxidation analysis or to be utilize as a parameter in life-time prediction of the DH pipe.Bundesministerium für Wirtschaft und Energi
Evaluation einer neugestalteten Radverkehrsführung am Beispiel des Knotenpunktes Tangstedter Landstraße / Gehlengraben
Get PDFIn dieser Bachelorarbeit wurde eine neugestaltete Radverkehrsführung an einem Knotenpunkt mithilfe verschiedener Techniken der Verkehrsbeobachtung evaluiert. Mögliche Konfliktstellen, Engstellen der Radverkehrsführung und Nutzungskonflikte mit anderen Verkehrsteilnehmenden wurden identifiziert. Für diese Konfliktstellen wurden Optimierungsmaßnahmen entwickelt, welche den Radverkehr beschleunigen und ihm eine höhere Priorität in der Verkehrsführung einräumen
Urban Hygiene and Slum Clearance as Catalysts: The Emergence of the Sanitary City and Town Planning
Get PDFIn the context of the rapid urbanization process in England and Germany, environmental and hygiene issues took on a new priority. Above all, the poorer classes and their housing problems and unsanitary living conditions threatened to become a danger for the middle and upper classes as well. With innovations in water supply, engineers tried to make the problem manageable. The urban hygiene movements became the motor for social controls and reforms, which were implemented again as part of urban planning measures to clean up slums. The slum clearance projects of the cities − examined here using the example of Hamburg and London – which were intended reformist, were often Janus-faced and often went hand in hand with conditioning and disciplining measures. Town planning as discipline – emerging in the late 19th century − should contribute to the questioning of “secured” knowledge from other disciplines. The uncritical transfer of “facts” from urban hygiene was often seamlessly translated into normative concepts of town planning. Knowledge stocks from other disciplines are to be contextualized in the social and political context before they are taken over without reflection. The history of town planning offers sufficient examples on the basis of which this can be documented