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Reducing the water stress inflicted by Sweden’s food consumption on other countries through sustainable food options - Study focusing on the water stress Sweden inflicts due to coffee and meat import
(2024) Nika, Drini; Chamoun, Elias; Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Rauch, Sébastien
This study delves into strategies for Sweden to curtail food imports from water-stressed nations and advance sustainable food production. Initially, we calculate the water footprint of meat and coffee consumption in Sweden, evaluating its impact on both Sweden and its importing countries. The main findings reveal that while Sweden's water stress in 2020 was 3.58%, transitioning to 100% environmentally friendly options, such as producing alternatives to imported coffee and meat within Sweden, resulted in a 0.0214% increase in the country's water stress, thereby increasing Sweden's water stress by a small margin. This would, however, significantly decrease the water stress for other countries which Sweden imports from. The study then explores solutions, emphasizing increased domestic production, water-efficient practices, and consumer awareness. Shifting from meat to plant-based alternatives and opting for sustainable coffee substitutes reduces Sweden's water footprint. The conclusion underscores the significance of transitioning to environmentally friendly options like plant-based meat and chicory plants to foster a resilient and sustainable food system in Sweden while minimizing water stress on other nations.
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Cost-Benefit Analysis and Environmental Impact of Water Management - A Case study on the West Link Railway project
(2024) Hadi, Farid; Nuur, Abdullahi; Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Hvitt Strömvall, Ann-Margret; Norrman, Jenny
This report examines the treatment efficiency of excess water and the socio-economic implications of managing this water during the construction of the West Link railway project in Gothenburg, Sweden. Approximately 130,000 cubic meters of excess water require annual treatment at the 'Centralen' site of the West Link project. Data from the Swedish Transportation Administration (STA) collected between 2018 and 2023 on water quality before and after treatment, and the associated costs were analysed. Findings show that the treatment plants achieve an average pollutant removal efficiency of 73%. However, variations in pollutant concentrations in the influent water, and the impact of maintenance practices underscore the importance of continuous monitoring and optimization of the treatment methods. This is essential to ensure high removal efficiency and that the effluent water complies with environmental standards. While the total mass of pollutants released annually, such as suspended solids, oil, arsenic, lead, cadmium, copper, total chromium and chromium VI, nickel, mercury, zinc, and pH give a small contribution to the Göta river compared to background levels, local releases from the construction site could still impact the nearby ecosystem and accumulate in organisms. Thus, stringent environmental protection measures remain necessary. A Cost-Benefit Analysis (CBA) was conducted, revealing that although the STA incurred substantial costs for the water treatment facility, there are significant public health and environmental benefits. In conclusion, the report emphasises the importance of effective water treatment to meet environmental regulations, mitigate ecological and health risks, and promote sustainable construction practices.
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Design, analysis and construction of hydrostatic masonry bridges: An assessment of load capacity using the discrete element method and physical scale models
(2024) Forsberg, Jacob; Svedjer, Emil; Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Ander, Mats; Adiels , Emil
Masonry is a building technique extensively used throughout history in different applications. However, structures in concrete have become common practice during the last century. Even though masonry bridges cover a large portion of existing bridges, and are a sustainable choice because of their adaptability and long service life, sufficient methods to assess and design masonry bridges are not clear. In this master thesis, the collapse load of masonry bridges designed as hydrostatic shells is investigated. The methods used are hand calculations, load tests on phys ical scale models and computational analysis using the Discrete Element Method (DEM). To validate the computational method an analysis is performed on a simple masonry arch as it is a known case. To validate the computational method, an analysis is performed on a simple masonry arch, a well-documented case, thereby obtaining useful coefficients for the unproven concept of the hydrostatic bridge. The form finding process is done in Rhinoceros3D and Grasshopper, and the geom etry created is used to model both the Discrete Element Model and the physical model. The hand calculations provided highly conservative results, as the resulting collapse load from the DEM analysis is 66 times larger and from the physical load test six times larger. The computational and physical models behave similarly when loaded, and both indicate that the critical loading position is in the midspan of the bridge. The physical model was loaded with 13.9 kg before collapse. By applying dimensional scaling, this result translates to 46.9 tonnes for a full-scale bridge. This indicates that the bridge concept is viable at full-scale. The result from the DEM analysis is qualitatively good but over-estimates the collapse load. Further work includes adding features to the computational model to provide more reliable results and investigating different geometries for the hydrostatic bridge.
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An Optimization and Cluster based Approach to Lookup Tables in Design of Adaptive Restraint Systems
(2024) Ashok Kumar, Rahul Dasikatte; Anand, Pranav; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Isaksson, Ola; Arjomandi Rad, Mohammad; Wehrmeyer, Lara; Balague, Henrik
The timely deployment of vehicle restraint systems is crucial in mitigating the impact of collisions and protecting occupants in the affected vehicles. The level of protection can be further enhanced with the use of adaptive restraint systems, by adjusting the force and timing of seatbelts and airbags based on factors such as vehicle speed, occupant size, and seating position. Virtual testing methods can help identify areas of improvement of adaptive systems by evaluating its performance across a range of crash scenarios. While finite element simulation models and data-based surrogate models have been used in literature for restraint system development, data structures such as lookup tables containing restraint settings offer potential to accelerate the design and deployment of adaptive restraint systems. To implement this, firstly, metamodels using Gaussian process regression were developed to predict specific occupant kinematics and injury risks in frontal collisions between vehicles with varying crash configurations. Furthermore, the optimal restraint settings for each crash configuration was identified using a genetic algorithm, taking into account the injury risk predictions from the metamodels. The frontal collisions were categorized based on crash pulse intensities and then represented in a static lookup table for quick retrieval of restraint settings based on a crash configuration. The restraint settings obtained from the optimization were validated with real-world equivalent settings, exhibiting lower injury risks in low and medium-speed crashes for the concerned vehicle model. Overall, the research presented demonstrates the application of lookup tables as a tool for development and operation of adaptive restraint systems. Furthermore, the combination of look-up tables with machine learning techniques could be scaled to suit the complexity of the engineering problem
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Utveckling av staket med integrerad solcellsteknik
(2024) El Masri, Mohammed Ali; Forsman, Niklas; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Boldizar , Antal; Hansson, Mattias
This study aims to develop an embodied concept for a fence with integrated solar cell technology, specifically designed for gardens and urban environments. The project, commissioned by Raymond Solar AB, focuses on creating a scalable and sustainable product that meets both current and future demands within solar energy, while being tailored to the Nordic climate and compatible with Raymond Solar’s existing products. The central challenge is designing a fence that is cost-effective to manufacture and easy to assemble, while ensuring that it withstands the climatic challenges, has a low environmental impact, and is both functional and aesthetically pleasing. A particular challenge was to make the fence adjustable to allow for some tolerance in the positioning and inclination of the ground screws, which is crucial for ensuring a smooth and rapid installation. Additionally, the construction needed to be compatible with different types and sizes of solar panels to maximize flexibility. The project was conducted through a combination of literature reviews, competitor analyses, and computer-assisted testing. Traditional technologies and competitor solutions were thoroughly examined to gather relevant data. Functional analyses and specifications were established to ensure that the product meets all necessary functions and requirements. CAD software was used for design, while strength analyses were conducted using FEA software. The study resulted in a modular fence construction made of aluminum, with posts, bottom rails, panels, footings, and fittings. The design is easy to assemble with few screws and includes T-slots for flexible installation of solar panels. Additionally, the fence is ergonomic and time-saving during installation, and the design allows for adjustments to handle deviations in the placement and inclination of ground screws. The construction is also compatible with various types and dimensions of solar panels, increasing flexibility and enabling adaptation to different installation needs. The production offers the possibility of using recycled materials, and the fence is fully recyclable, significantly reducing its environmental impact. The study concludes that the developed fence with integrated solar cell technology meets the criteria for sustainability, cost-effectiveness, and ease of assembly. The robust construction ensures that the fence can withstand the challenges of the Nordic climate and offers a solution that is both environmentally friendly and practical for consumers and installers