The hygrothermal analysis of building envelopes plays a crucial role in the renovation strategies for historical buildings. Dynamical hygrothermal simulations under realistic conditions are effective in predicting moisture-related damages, including the risk of mold growth or frost damage, which can arise when combining historical walls with modern insulation systems. However, accurately modeling and simulating historic walls, composed of brick/stone and mortar joints, using detailed two- or three-dimensional models, is a complex and time-consuming task. As a result, a common practice in hygrothermal simulations is to simplify old masonry into a one-dimensional layer of stone/brick, disregarding mortar joints. Nonetheless, in this study cases were identified where this simplification approach leads to unacceptable inaccuracies, particularly when historic masonry is combined with vapor-tight insulation systems. Also, this study investigated the influence of the internal geometry of mortar joints and the stone/mortar ratio in hygrothermal simulations. While the internal disposition of joints showed minimal influence, the stone/mortar ratio was found to play a significant role. In light of these findings, this thesis proposes a method to replace the complex representation of historical masonry with a fictitious homogenized porous material that incorporates the influence of mortar joints. The hygrothermal properties of this newly developed ‘Homogenized Porous Material’ are averaged and optimized to closely approximate the behavior of the hygrothermal model for important applications. The proposed method was applied to various combinations of mortars, stones, and bricks. Furthermore, the behavior of the ‘Homogenized Porous Material’ was evaluated under dynamic conditions, specifically for the case of an internally insulated wall in different climates. A comparison was made with a two-dimensional fully described model to assess the performance of the developed method. The results demonstrate considerable improvements compared to the conventional one-dimensional stone/brick layer approximation, with the degree of improvement being more pronounced when the hygrothermal properties of the stone/brick and mortar differ significantly. The developed method offers significant advantages: for example, the application to 3D building energy simulation tools which entangle moisture balances, allows for quick pre-checks for moisture damage. This can help pre-assessing the potential risks of moisture-related issues in a time-efficient manner also at building component level. Moreover, in time-critical studies where a large number of variant analyses are required, 1D models remain essential as they allow for efficient sensitivity analyses with a large number of simulations runs. This method facilitates a comprehensive exploration of different scenarios and parameter variations, aiding in the identification of critical factors affecting the hygrothermal performance of historic walls. Furthermore, the developed method has potential applications in situations where the inner structure of walls is unknown, such as forensic analysis of historical constructions. By providing a reliable and simplified representation of the hygrothermal behavior, this method can support investigations and assessments of moisture-related issues in historical buildings, even when detailed knowledge of the internal structure is limited. In conclusion, this research can offer to architects and engineers practical benefits in terms of accurate prediction of moisture-related damages, efficient pre-checks, sensitivity analyses, and applications in cases with limited knowledge of wall structures. In future, an extended database of ‘Homogenized Porous Materials’, suitable to model masonry walls, can be built for the users.:Preface Abstract Kurzfassung Table of Contents Chapter 1 - Introduction and overview 1.1 Motivation 1.2 Problem statement 1.3 Thesis 1.4 Solution strategy and methodology 1.5 Structure of the study Chapter 2 - Literature background 2.1 General concepts concerning historical masonry 2.2 Theory and tool for hygrothermal simulations 2.2.1 Balance equation of energy and mass for the porous medium 2.2.2 Flux of energy and mass for the porous medium 2.2.3 Climate and boundary conditions Incident wind-driven rain Radiation, short-wave and long-wave Interior climate 2.3 Main hygrothermal properties of materials and experimental measurement procedures 2.3.1 Bulk density and porosity: helium pycnometer 2.3.2 Specific heat capacity: calorimeter 2.3.3 Thermal conductivity: the hot plate measurement 2.3.4 Vapour conductivity: the cup-tests 2.3.5 Moisture storage function: desiccator method and pressure plates 2.3.6 Liquid conductivity: water uptake and drying experiment 2.3.7 Vapor and liquid conductivity function: capillary condensation redistribution test (CCR) 2.4 Complexity and simplification for the hygrothermal modeling and simulation of historical masonry Chapter 3 - Quantifying the Impact of Mortar Joints in Hygrothermal Simulations of Historical Masonry 3.1 Investigation through dynamical hygrothermal simulation in realistic condition 3.2 Evidence of mortar joints’ impact in hygrothermal simulations of historic walls 3.3 Dependence of the hygrothermal transport of a masonry wall on its internal geometry 3.4 Discrepancies due to assumptions on stone/mortar ratio 3.5 The case of a three-dimensional simulation Chapter 4 - A fictitious ‘Homogenized Porous Material’ (HPM) to describe heat and moisture transport in a massive historic wall 4.1 Definition of the preliminary activities: choice of the reference model and of the materials 4.2 Homogenized porous material characterization 4.2.1 Phase 1: hygrothermal properties through analytical calculation Bulk density, ρ Porosity, θpor Specific heat capacity, Cp Moisture storage function, θl,HPMpc 4.2.2 Phase 2: hygrothermal properties through numerical experiment Dry Thermal conductivity, λdry Thermal conductivity function, λ(θl) Dry water vapour resistance factor, μdry Water vapour conductivity function, Kv(θl) 4.2.3 Phase 3: hygrothermal properties through optimization algorithm 4.3 Conclusions on the developed method Chapter 5 - Application of the ‘Homogenized Porous Material’ (HPM) method 5.1 Preliminary activities and reading instructions 5.2 Homogenized Porous Material characterizations in three phases 5.3 Dynamical hygrothermal simulation in realistic condition with Homogenized Porous Materials 5.3.1 Simulations set-up 5.3.2 Analyzed Output 5.3.3 Result of the simulation in realistic design condition with Interior Insulation 5.4 Discussion on the obtained results 5.4.1 Discussion on HPM calibration results 5.4.2 Discussion on HPM dynamical hygrothermal simulation in realistic condition 5.5 Conclusions on the tests Chapter 6 - Summary, conclusions and outlooks 6.1 Content summary 6.2 Achievements and conclusions 6.3 Future prospects Appendix I List of Figures (Appendix I) List of Tables (Appendix I) Appendix II List of Figures (Appendix II) Appendix III List of figure (Appendix III) List of Tables (Appendix III) List of Abbreviations and Symbols List of Figures List of Tables Acknowledgements Bibliography

The increasing share of renewable energies in the power sector influences the economic viability of investments in new conventional power plants. Many studies have investigated these issues by considering power plant operation or the long-term development of the power plant fleet. However, power plant decommissioning, investment and operation are intrinsically linked. This doctoral thesis therefore presents a modelling framework for an integrated consideration of power plant decommissioning, investment and operation. In a case study focusing on Germany, the effects of the integration of renewable energies on power plant decommissioning, investment and operation are evaluated in the context of different assumptions regarding the remaining lifetime of nuclear power plants. With regard to the use of nuclear power, a phase-out scenario and a scenario with lifetime extension of nuclear power plants (by on average 12 years) are considered. The results show that static decommissioning (i.e. considering fixed technical lifetimes) underestimates the capacity available in the power sector in the scenario without lifetime extension since retrofit measures (versus decommissioning) are not taken into account. In contrast, capacity available in the case of nuclear lifetime extension is overestimated since mothballing (versus regular operation) is not considered. If the impact on decommissioning decisions of profit margins accrued during power plant operation are considered (“dynamic decommissioning”), the electricity price reduction effect due to a lifetime extension is reduced by more than half in comparison to static decommissioning. Scarcity situations do not differ significantly between the scenarios with and without lifetime extension with dynamic decommissioning; in contrast, there is a significantly higher need for imports without lifetime extension with static decommissioning. The case study demonstrates that further system flexibility is needed for the integration of renewable energies. It can be further concluded that the share of flexible power plants is higher with the phase-out of nuclear power plants. With regard to the decommissioning dynamics, the phase-out can be considered as beneficial for the economic viability of fossil power plants. Furthermore, the phase-out does not, overall, lead to environmental disadvantages in the medium term, but may be beneficial in the long run since lock-in effects are avoided. Further research is required with regard to the consideration of future flexibility options and a new market design. / Der steigende Anteil erneuerbarer Energien beeinflusst die Wirtschaftlichkeit von Investitionen in neue konventionelle Kraftwerke. Zahlreiche Studien haben diese Aspekte in Bezug auf den Kraftwerksbetrieb oder die langfristige Entwicklung des Kraftwerksparks untersucht. Stilllegungen, Investitionen und Betrieb im Kraftwerkspark bedingen jedoch einander. Aus diesem Grund wird in dieser Doktorarbeit ein Modellierungsansatz für eine integrierte Betrachtung von Kraftwerksstilllegung, -investition und -betrieb vorgestellt. In einer Fallstudie für Deutschland werden die Auswirkungen einer Integration erneuerbarer Energien auf Kraftwerksstilllegung, -investition und -betrieb im Zusammenhang mit unterschiedlichen Annahmen über die Restlaufzeit von Kernkraftwerken untersucht. Bezogen auf die Nutzung der Kernenergie wird hierbei ein Ausstiegsszenario sowie ein Laufzeitverlängerungsszenario (Verlän-gerung der Laufzeit um durchschnittlich 12 Jahre) betrachtet. Die Ergebnisse zeigen, dass die statische Stilllegung (d.h. die Betrachtung fester technischer Lebensdauern) im Fall eines Verzichts auf die Laufzeitverlängerung die im Kraftwerkspark verfügbare Leistung unterschätzt, da Retrofit-Maßnahmen (im Vergleich zur Stilllegung) nicht berücksichtigt werden. Die verfügbare Leistung im Falle einer Laufzeitverlängerung wird dagegen überschätzt, da die Möglichkeit der Kaltreserve (im Vergleich zum regulären Betrieb) vernachlässigt wird. Werden die Rückwirkungen der im Betrieb erwirtschaftbaren Deckungsbeiträge auf Stilllegungsentscheidungen (“dynamische Stilllegung”) betrachtet, so wird der strompreissenkende Effekt durch die Laufzeitverlängerung im Vergleich zur statischen Stilllegung mehr als halbiert. Knappheitssitutationen unterscheiden sich nicht wesentlich mit und ohne Laufzeitverlängerung im Fall der dynamischen Stilllegung, während bei statischer Stilllegung ohne Laufzeitzeitverlängerung ein deutlich größerer Importbedarf besteht. Die Fallstudie zeigt, dass weitere Systemflexibilitäten für die Integration erneuerbarer Energien benötigt werden. Der Anteil flexibler Kraftwerke ist größer im Fall des Kernenergieausstiegs. Der Kernenergieausstieg wirkt sich in Bezug auf die Stilllegungsdynamik positiv auf die Wirtschaftlichkeit fossiler Kraftwerke aus. Insgesamt führt der Kernenergieausstieg zu keinen mittelfristig nachteiligen Umwelteffekten, er kann sich jedoch langfristig positiv auswirken, da Lock-in-Effekte vermieden werden. Es besteht weiterer Forschungsbedarf in Bezug auf die Berücksichtigung künftiger Flexibilitätsoptionen und ein neues Marktdesign.

[pt] O Rio de Janeiro é uma cidade de alta densidade demográfica em uma situação geográfica excepcional, entre o mar, as montanhas e diversas lagoas. Uma parcela de sua população, de aproximadamente 6 milhões de habitantes, vive em edifícios de apartamentos. Em muitos bairros não há mais terrenos disponíveis para novas edificações. A construção sustentável é necessária para redução de consumos e desperdícios, assim como a fundamental atenção a aspectos de conforto ambiental e sociais (o morador). Visando a melhoria da qualidade de vida e para atingir um estágio de sustentabilidade será necessário pensar em como aperfeiçoar os edifícios e quadras existentes. Na cidade do Rio de Janeiro há diversos proprietários e locatários, sendo importante elaborar uma estratégia específica para desenvolver uma renovação do parque construído. A presente tese aborda: os edifícios residenciais no Rio de Janeiro (e a legislação), a construção sustentável, a renovação de edifícios e quadras, recomendações para projetos de acordo com as características climáticas e verificações sobre as condições existentes (físicas, ambientais e sociais). Foi desenvolvido um estudo de caso em uma quadra típica no famoso e de alta densidade demográfica bairro de Copacabana (96 porcento de seus moradores vivem em apartamentos, sendo 1/3 com mais de 60 anos) que teve praticamente todos os seus prédios e quadras construídos entre 1940 e 1960 com características semelhantes como: estrutura em concreto, edifícios de 10 e 12 pavimentos e com pouco ou nenhum afastamento entre si. / [en] Rio de Janeiro is a very dense city in an exceptional geography situation between the sea, the mountains and some lakes. The population of six million inhabitants only in the municipality area lives mainly in apartments buildings. In some neighborhoods there are no empty sites for new constructions. Sustainable construction is a necessary step to reduce the consumption and the waste, and also the focus in the comfort conditions and social aspects (the dwellers). To improve the quality of living and achieve the environmental goals it is necessary to think how to upgrade the quality of existing buildings and blocks. In Rio de Janeiro each building has different owners and dwellers, and it will be important to work in a specific strategy to develop the building stock renovation. This thesis involves: apartment buildings in Rio de Janeiro (including the legislation), sustainable construction, renovation (refurbishment) of buildings and blocks, design recommendations according to the climatic conditions in Rio de Janeiro, and the verification of apartment building conditions (physical, environmental and social). One case study in a regular block of a very dense and famous neighborhood named Copacabana (96 percent of dwellers in this neighborhood live in apartments and 1/3 is older than 60 years old) was developed. Copacabana has almost all the buildings and blocks built during the 1940 and 1960 decades with common features like: concrete structure, buildings with 10 to 12 floors, and no distance between them.

The diploma thesis deals with the issue of replacement of non-ecological refrigerant R22 according to the requirements of relevant juristic regulations and of subsequent influence of this replacement to the efficiency of air conditioning systems. The theoretical part is focused on proceeding processes in thermodynamic cycles and during heat transfer, then determines calculation of cooling and heating factor in context with experimental measurement. The experimental measurement utilizes to the assessment of operation of heat pump after refrigerant replacement and it is source for the composion of economical evaluation of alternative solutions due to the particular choice of refrigerant replacement.

Legally binding targets set by the UK government to reduce carbon emissions by 2050 mean it is imperative that the efficiency of the UK housing stock is improved. Housing currently contributes over 30% of the UK s total carbon emissions and a large proportion of the current stock will still exist in 2050. There is therefore a need to retrofit this existing stock with energy saving measures, as the savings from new builds will not be adequate to meet the stringent carbon reduction targets. Whilst technologies to facilitate energy saving retrofit are available, there has been a low uptake from householders in the UK, in part due to the lack of consideration of user requirements within the design of these technologies. To investigate this issue further, this thesis considers two main questions: How can the design of energy saving measures and the process of retrofit of the existing UK housing stock be improved through the use of user centred design (UCD) and How can UCD methods be applied to the research and development process for energy saving measures in order to improve the outcome? Through the research, it became clear that in order to answer these questions, it would be necessary to work across disciplines and therefore a third Research Question was posed; How can UCD facilitate working across disciplines in the context of an energy research project? The results provide evidence of how UCD can effectively improve the design and development process of energy saving technologies, the process of retrofit and the practice of cross-disciplinary working within a research environment. The research is novel in several ways: firstly, the UCD process has been applied in the area of domestic retrofit, giving new insights into the barriers and opportunities to retrofit; secondly, home improvement has been investigated by viewing the home as a complete, interacting system, using novel methods; thirdly, a set of UCD specifications have been created to inform the design of heat pumps, a specific domestic energy saving technology, and finally, enhancements to the UCD process are made for use within an energy technology project, together with the development of six principles for effective cross-disciplinary working and conceptualisation of the bridge building role which the UCD practitioner fulfills.

The effectiveness of seismic retrofitting applied to enhance seismic performance was assessed for a five-story reinforced concrete (RC) flat-slab building structure in the central United States. In addition to this, an assessment of seismic fragility that relates the probability of exceeding a performance level to the earthquake intensity was conducted. The response of the structure was predicted using nonlinear static and dynamic analyses with synthetic ground motion records for the central U.S. region. In addition, two analytical approaches for nonlinear response analysis were compared. FEMA 356 (ASCE 2000) criteria were used to evaluate the seismic performance of the case study building. Two approaches of FEMA 356 were used for seismic evaluation: global-level and member-level using three performance levels (Immediate Occupancy, Life Safety and Collapse Prevention). In addition to these limit states, punching shear drift limits were also considered to establish an upper bound drift capacity limit for collapse prevention. Based on the seismic evaluation results, three possible retrofit techniques were applied to improve the seismic performance of the structure, including addition of shear walls, addition of RC column jackets, and confinement of the column plastic hinge zones using externally bonded steel plates. Finally, fragility relationships were developed for the existing and retrofitted structure using several performance levels. Fragility curves for the retrofitted structure were compared with those for the unretrofitted structure. For various performance levels to assess the fragility curves, FEMA global drift limits were compared with the drift limits based on the FEMA member-level criteria. In addition to this, performance levels which were based on additional quantitative limits were also considered and compared with FEMA drift limits.

Mitigation of the blast risk associated with terrorist attacks and accidental explosions threatening critical infrastructure has become a topic of great interest in the civil engineering community, both in Canada and abroad. One method of mitigating blast risk is to retrofit vulnerable structures to resist the impulsive effects of blast loading. A comprehensive re-search program has been undertaken to develop fibre reinforced polymer (FRP) retrofit methodologies for structural and non-structural elements, specifically reinforced concrete slabs and walls, subjected to blast loading. The results of this investigation are equally valid for flexure dominant reinforced concrete beams subject to blast effects. The objective of the research program was to generate a large volume of research data for the development of blast-resistant design guidelines for externally bonded FRP retrofit systems. A combined experimental and analytical investigation was performed to achieve the objectives of the program. The experimental program involved the construction and simulated blast testing of a total of thirteen reinforced concrete wall and slab specimens divided into five companion sets. These specimens were subjected to a total of sixty simulated explosions generated at the University of Ottawa Shock Tube Testing Facility. Companion sets were designed to study one- and two-way bending, as well as the performance of specimens with simply-supported and fully-fixed boundary conditions. The majority of the specimens were retrofitted with externally bonded carbon fibre reinforced polymer (CFRP) sheets to improve overall load-deformation characteristics. Specimens within each companion set were subjected to progressively increasing pressure-impulse combinations to study component behaviour from elastic response up to inelastic component failure. The blast performance of companion as-built and retrofitted specimens was quantified in terms of measured load-deformation characteristics, and observed member behaviour throughout all stages of response. The results show that externally bonded FRP retrofits are an effective retrofit technique to improve the blast resistance of reinforced concrete structures, provided that debonding of the composite from the concrete substrate is prevented. The test results also indicate that FRP retrofitted reinforced concrete structures may survive initial inbound displacements, only to failure by moment reversals during the negative displacement phase. The experimental test data was used to verify analytical techniques to model the behaviour of reinforced concrete walls and slabs subjected to blast loading. The force-deformation characteristics of one-way wall strips were established using inelastic sectional and member analyses. The force-deformation characteristics of two-way slab plates were established using commonly accepted design approximations. The response of all specimens was computed by explicit solution of the single degree of freedom dynamic equation of motion. An equivalent static force procedure was used to analyze the response of CFRP retrofitted specimens which remained elastic after testing. The predicted maximum displacements and time-to-maximum displacements were compared against experimental results. The analysis indicates that the modelling procedures accurately describe the response characteristics of both retrofitted and unretrofitted specimens observed during the experiment.

The purpose of this research is to determine the average energy intensity of multi-unit residential buildings (MURBs) in Toronto, and evaluate whether certain building characteristics influence energy intensity. This information is particularly important in the Toronto market. Relative to the city’s population, Toronto has an unusually high proportion of MURBs with more than half of residential dwellings in apartment buildings. Additionally, Toronto MURBs are significant consumers of energy and produce an estimated 1.3M tonnes of CO2e each year. The ultimate goal is to assess the most efficient building retrofit measures. Energy consumption data for Toronto MURBs were collected and weather normalized. Correlations between the energy data and the building characteristics were examined. Window characteristics and heating system type were found to have the most significant influence on energy intensity. Establishing energy consumption characteristics of MURBs is the first step towards improving the energy efficiency of Toronto’s MURBs stock.

The purpose of this research is to determine the average energy intensity of multi-unit residential buildings (MURBs) in Toronto, and evaluate whether certain building characteristics influence energy intensity. This information is particularly important in the Toronto market. Relative to the city’s population, Toronto has an unusually high proportion of MURBs with more than half of residential dwellings in apartment buildings. Additionally, Toronto MURBs are significant consumers of energy and produce an estimated 1.3M tonnes of CO2e each year. The ultimate goal is to assess the most efficient building retrofit measures. Energy consumption data for Toronto MURBs were collected and weather normalized. Correlations between the energy data and the building characteristics were examined. Window characteristics and heating system type were found to have the most significant influence on energy intensity. Establishing energy consumption characteristics of MURBs is the first step towards improving the energy efficiency of Toronto’s MURBs stock.

Mitigation of the blast risk associated with terrorist attacks and accidental explosions threatening critical infrastructure has become a topic of great interest in the civil engineering community, both in Canada and abroad. One method of mitigating blast risk is to retrofit vulnerable structures to resist the impulsive effects of blast loading. A comprehensive re-search program has been undertaken to develop fibre reinforced polymer (FRP) retrofit methodologies for structural and non-structural elements, specifically reinforced concrete slabs and walls, subjected to blast loading. The results of this investigation are equally valid for flexure dominant reinforced concrete beams subject to blast effects. The objective of the research program was to generate a large volume of research data for the development of blast-resistant design guidelines for externally bonded FRP retrofit systems. A combined experimental and analytical investigation was performed to achieve the objectives of the program. The experimental program involved the construction and simulated blast testing of a total of thirteen reinforced concrete wall and slab specimens divided into five companion sets. These specimens were subjected to a total of sixty simulated explosions generated at the University of Ottawa Shock Tube Testing Facility. Companion sets were designed to study one- and two-way bending, as well as the performance of specimens with simply-supported and fully-fixed boundary conditions. The majority of the specimens were retrofitted with externally bonded carbon fibre reinforced polymer (CFRP) sheets to improve overall load-deformation characteristics. Specimens within each companion set were subjected to progressively increasing pressure-impulse combinations to study component behaviour from elastic response up to inelastic component failure. The blast performance of companion as-built and retrofitted specimens was quantified in terms of measured load-deformation characteristics, and observed member behaviour throughout all stages of response. The results show that externally bonded FRP retrofits are an effective retrofit technique to improve the blast resistance of reinforced concrete structures, provided that debonding of the composite from the concrete substrate is prevented. The test results also indicate that FRP retrofitted reinforced concrete structures may survive initial inbound displacements, only to failure by moment reversals during the negative displacement phase. The experimental test data was used to verify analytical techniques to model the behaviour of reinforced concrete walls and slabs subjected to blast loading. The force-deformation characteristics of one-way wall strips were established using inelastic sectional and member analyses. The force-deformation characteristics of two-way slab plates were established using commonly accepted design approximations. The response of all specimens was computed by explicit solution of the single degree of freedom dynamic equation of motion. An equivalent static force procedure was used to analyze the response of CFRP retrofitted specimens which remained elastic after testing. The predicted maximum displacements and time-to-maximum displacements were compared against experimental results. The analysis indicates that the modelling procedures accurately describe the response characteristics of both retrofitted and unretrofitted specimens observed during the experiment.