Repaso 1-6 PDF: Building and Construction Materials
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Uploaded by PreciousZither
Technical University of Denmark
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This document contains questions and answers about sustainable building and construction materials. It covers topics such as carbon emissions, innovative materials, and green construction strategies.
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1. What percentage of carbon emissions is attributed to building and construction? 40% 2. What are the top five most used materials in construction? Aluminum Fiberglass Insulation Steel glass 3. What is the "green transition" in the context of construction materials?...
1. What percentage of carbon emissions is attributed to building and construction? 40% 2. What are the top five most used materials in construction? Aluminum Fiberglass Insulation Steel glass 3. What is the "green transition" in the context of construction materials? Using sustainable materials and methods to support environmental sustainability. Minimize waste, energy and emissions. 4. What strategies are employed in the green transition for construction materials? energy-efficient building designs using low-carbon materials designing efficient structures that maximize natural light using innovative technologies like phase-change materials and self-healing concrete. 5. What innovative materials are mentioned for sustainable construction? Carbon-cured concrete Cross-laminated timber (which sequesters CO2) Geopolymer concrete (made from fly ash and slag) Self-healing concrete 6. How does cross-laminated timber contribute to CO2 sequestration? Cross-laminated timber contributes to CO2 sequestration by storing carbon during its growth phase as a renewable resource, locking the carbon within the material, and reducing reliance on high-emission materials like concrete and steel. 7. What is self-healing concrete, and how does it work? Bacteria-based and microcapsules (react with water and air to fill cracks with calcium carbonate). 8. What are the main components of cement and concrete? Cement: Limestone Clay heated together at high temperatures in a kiln to form clinker. The clinker is then ground into a fine powder, which becomes cement. Concrete: Aggregates (sand and gravel) Water cement 9. How does the process of cement formation contribute to CO2 emissions? Mainly due to limestone decarbonization 10. What are supplementary cementitious materials (SCMs), and how are they made? SCMs are materials used to partially replace cement in concrete, reducing its carbon footprint. Traditional ones are made of: coal fly ash (silica rich) silica fume slag cements Modern SCMs: calcined clays various wastes mine tailings 11. What are the advantages of concrete as a construction material? Cheap Formable durable 12. What factors affect the durability of concrete? Exposure class Degradation mechanisms like corrosion and freeze-thaw cycles transport mechanisms (how fluids move through concrete) Pore structure Pore volume Permeability binding quality 13. What are the policies and certifications related to sustainable construction mentioned in the lectures? Policies: Bygningreg EPBD Certifications: BREEAM LEED 14. What are smart materials, and how are they applied in construction? 15. What is the main contributor to emissions in steel production? extraction and processing of iron ore, which requires significant energy 16. What’s the role of the calcium hydroxide? Forms as a result of the cement hydration Creates a high pH>12 that allows for the formation of the passivation layer which protects from the corrosion of steel If it reacts with CO2 it leads to carbonation, creating calcium carbonate, lowering pH and leading to structural damage 17. What percentage of carbon emissions comes specifically from construction materials? 16% 18. What are the main points of the building and construction green transition? Reduce waste Reduce water use Reduce emissions Reduce energy use 19. What are the benefits of cross-laminated timber in sustainable construction? Easy to assembly Good strength to weight ratio Thermal insulation Lightweight CO2 sequestration 20. What materials are used to make geopolymer concrete? Waste from industry like fly ash and slag 21. How is carbon-cured concrete made, and why is it important for sustainability? 22. What are phase-change materials (PCMs), and how do they contribute to sustainable construction? 23. What are the two types of green concrete mentioned in the notes? Geopolymer and carbon-cured 24. How does modular construction contribute to sustainability in building? 25. What are supplementary cementitious materials (SCMs), and what are they traditionally made of? Used for the production of concrete, mixed with cement, therefore reducing cement content. Enhances strength, durability and workability other features and reduced carbon footprint. 26. What are some modern SCMs? Mine tailings, from wastes, calcinated clay 27. What is conventional casting in concrete placement Conventional casting is when concrete is poured into a pre-constructed mold, allowing it to harden in place. 28. What are the advantages of 3D-printed concrete in construction? reduced labour reduced waste reduced timeline enhanced design shapes