| 1. |
- Al-Ayish, Nadia
(författare)
-
Environmental Impact of Concrete Structures - with Focus on Durability and Resource Efficiency
- 2017
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Concrete is essential for the construction industry with characteristic properties that make it irreplaceable in some aspects. However, due to the large volumes consumed and the energy intense cement clinker production it also has a notable climate impact. In order to reach the international and national sustainability goals it is therefore important to reduce the climate impact of concrete structures.There are many ways to influence the environmental impact of concrete and a detailed analysis is one of the actions that could push the industry and the society towards a sustainable development. The purpose of this research is to evaluate the environmental impact of concrete structures and the built environment and to highlight the possibilities to reduce that impact with choice of concrete mix and innovative design solutions.A life cycle assessment (LCA) was carried out to analyze the environmental impact of two thin façade solutions with innovative materials and to evaluate influences of different greenhouse gas reducing measures on concrete bridges. The influence of supplementary cementitious materials (SCM) in terms of climate impact and durability was also analyzed.The results indicate that SCMs have a twofold effect on the climate impact of reinforced concrete structures. Not only do they reduce the greenhouse gases through cement clinker replacement but also by an improvement of durability regarding chloride ingress. Currently, this is not considered in the regulations, which makes it difficult to foresee in LCA at early design stages. The results also show great possibilities to reduce the climate impact through different measures and design alternatives and the need for further development of products and solutions.
|
|
| 2. |
- Al-Ayish, Nadia, et al.
(författare)
-
Livslängden hos betongbroar: Erfarenheter och implementering med LCA/LCC
- 2020
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The lifespan of construction works is crucial to achieve a low environmental impact for aprovided function. Supplementary cementitious materials are increasingly used in concrete production where the effect on the service life of structures needs to be assessed. In order to achieve a long service life, the design, flexibility in the design and workmanship also needs to be addressed.Today’s LCC and LCA analyses are based on statistics of service life of older bridges and are not material specific. There is still a lack of information about how the service life of concrete bridges is affected by different measures. The overall goal of this project was to close this information gap. The project aimed at describing key factors that affect the lifespan of concrete bridges. Key factors may reflect aspects of both durability and the utility of the design. The purpose was to investigate how the service life can be included in LCA and LCC analyses and to create a basis for future LCA and LCC analyses of concrete road bridges.Factors affecting the service life of concrete bridges have been identified through a literature survey and interviews. The studies comprised the service life of concretebridges, durability, service life models, requirements and guidelines, previous LCA and LCC studies as well as service life-extending measures throughout the whole lifecycle from material production to the end-of-life.The studies showed that reinforcement corrosion caused by chlorides is the most common cause of damage in concrete bridges where the service life of parts of theconstruction is usually shorter than the design service life. Even though frost resistance has historically been more restricting when choosing a concrete composition. The restrictions have, however, been reduced lately but there needs to be more focus on finding a design method that takes into account the impact of the concrete composition regarding reinforcement corrosion in order to find the most suitable solution for each individual case.The study shows the service life of concrete bridges depends not only on the expert’s knowledge of concrete but also on quality of execution. There is great potential to extend the service life of concrete bridges and to reduce their climate impact. However, it is important that the service life-extending measures also have a low embodied impact.The results of the survey show that technology and cost are the highest priority for mostrespondents, except for researchers where the focus is more on the environment and durability. Many also consider that contractors should set more demands towards environmentally friendly solutions.The results are compiled in the form of recommendations for reduced environmental impact and costs, as well as for how an LCA and LCC can be carried out with regard to service life.
|
|
| 3. |
|
|
| 4. |
- Al-Ayish, Nadia, et al.
(författare)
-
The influence of supplementary cementitious materials on climate impact of concrete bridges exposed to chlorides
- 2018
-
Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 188, s. 391-398
-
Tidskriftsartikel (refereegranskat)abstract
- In order to reach a specific service life of reinforced concrete structures a certain cover thickness is needed. At present, this is regulated by national standards that also limit the amount and type of supplementary cementitious materials in different exposure environments. The regulations do not, however, consider the actual durability performance of concrete with supplementary cementitious materials. As a consequence, the LCA results might be misleading. This paper shows the environmental impact of concrete with supplementary cementitious materials in chloride environment considering their specific performances. Prescriptive and performance based service life prediction models for chloride ingress are applied and compared.
|
|
| 5. |
- During, Otto
(författare)
-
Betongens livscykel
- 2013
-
Ingår i: CBI-nytt. - 0349-2060. ; :2, s. 4-
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 6. |
|
|
| 7. |
- During, Otto, et al.
(författare)
-
Life cycle cost analysis on impregnated bridge edge beams
- 2014
-
Ingår i: Restoration of Buildings and Monuments. - 1864-7251. ; 20:6, s. 441–446-
-
Tidskriftsartikel (refereegranskat)abstract
- the edge beams. However, results from this study pointed out that in most cases there is a clear economic benefit to impregnate the bridge edge beams even if it has to be repeated every 15 years.
|
|
| 8. |
- During, Otto
(författare)
-
Livscykelanalys
- 2011
-
Ingår i: CBI-nytt. - 0349-2060. ; :1, s. 7-
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 9. |
- During, Otto
(författare)
-
Några reflexioner om LCA
- 2013
-
Ingår i: CBI-nytt. - 0349-2060. ; :1, s. 10-
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 10. |
- During, Otto, et al.
(författare)
-
Rice Husk Resource for Energy and Cementitious Products with Low CO2 contributions
- 2018
-
Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 59:2, s. 45-58
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Rice Husk Ash (RHA) is a well-known supplementary cementitious materials (SCMs) that can be used for concrete with reduced CO2 contributions. In 2016, only Nepal produced 5.2 million tonnes rice that gave about 1.14 million tonnes rice husk. The rice husk can also be used directly in a cement kiln as a fuel. This study analysis the potential CO2 reductions from three scenarios and emphasis strengths, weaknesses, opportunities and treats in the production systems for initiate a decision process with possibilities to get an industry project financed from the green climate found. The highest CO2 benefits were from rice husk used in a cement kiln were half of the yearly rice husk production in Nepal could reduce the climate impact with 808000 tonnes CO2.
|
|
| 11. |
- Grigoriadis, K., et al.
(författare)
-
Improving the recycling rate of the construction industry
- 2019
-
Ingår i: Sustainable Construction Materials and Technologies. - : International Committee of the SCMT conferences.
-
Konferensbidrag (refereegranskat)abstract
- Construction and Demolition Waste (CDW) accounts for approximately 25-30% of all waste generated across Europe each year. However, Waste Framework Directive 2008/98/EC requires from all EU member states to achieve at least 70% re-use, recycling or other recovery of non-hazardous CDW by 2020. In response, the Horizon 2020 RE4 Project (REuse and REcycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction) consortium was set up. Its main aims are to assess the quality of various CDW fractions (e.g. mineral aggregate, timber, plastics, silt & clay), improve the quality of mineral aggregates and develop different building elements/components which contain at least 65% of CDW. Innovative building concepts will also be developed in an effort to improve recycling rates of future buildings through the use of prefabrication and modular design. The developed products and technologies will be assessed in a number of test sites by building 2-storey demonstration houses.
|
|
| 12. |
- Kadawo, Abdinasir, et al.
(författare)
-
Combination of LCA and circularity index for assessment of environmental impact of recycled aggregate concrete
- 2023
-
Ingår i: Journal of Sustainable Cement-Based Materials. - : Informa UK Limited. - 2165-0373 .- 2165-0381. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- Multidisciplinary approach is used to evaluate concrete with recycled concrete aggregates (RCA) from technical, environmental impacts and product circularity perspectives. Two RCA replacements investigated, RAC50: fine aggregates; RAC100: both coarse, fine aggregates. Reference, recycled concretes have same cement content, similar workability and compressive strength requirement, proven experimentally. RCA is sourced from pre-fab element discards of a Swedish plant, the logistical alternatives requiring environmental impact analysis. Alternatives are RCA crushing at plant and crushing at a different location including transportation. LCA shows transportation is second largest contributor after cement in all impact categories. RAC alternatives show lower total impact than reference concrete due to RCA replacement. A circularity index for concrete based on economic value of recirculated aggregates; supplements LCA for sustainability reporting. Circularity index results: RAC100 > RAC50 > RC. Combining circularity index with LCA helps optimize recycling process with regard to amount of recycled material and logistics respectively.
|
|
| 13. |
- Kurkinen, Eva-Lotta, et al.
(författare)
-
Energi och klimateffektiva byggsystem : Miljövärdering av olika stomalternativ
- 2015
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In the collaborative forum Positive footprint housing® Riksbyggen is building the Viva residential quarter, which is a sustainability project at the very forefront of what is possible with contemporary construction. The idea is that this residential quarter should be fully sustainable in ecological, economic and social terms. Since 2013, a number of pilot studies have been completed under the auspices of the Viva project framework thanks to financing from the Swedish Energy Agency.The various building frame alternatives that have been evaluated are precast concrete, cast in-situ concrete and solid wood, all proposed by leading commercial suppliers. The report includes a specific requirement for equivalent functions during the use phase of the building, B. An interpretation has been provided that investigates the building engineering aspects in detail, as well as an account of the results based on the social community requirements specified in Viva, durability, fire, noise and energy consumption in the Swedish National Board of Building, Planning and Housing building regulations (BBR), plus Riksbyggen’s own requirements, Sweden Green Building Council’s Environmental Building Gold (Miljöbyggnad Guld) and 100-year life cycle. Given that the alternatives have different long-term characteristics (and also that our knowledge of these characteristics itself varies), these functional requirements have been addressed by setting up different scenarios in accordance with the EPD standard EN 15978.Because Riksbyggen has specified a requirement for a 100-year life cycle, we have also opted for an analysis period of 100 years.The results show no significant differences between concrete and timber structures for the same functions during the life cycle, either for climate or for primary energy. The minor differences reported are accordingly less than the degree of uncertainty involved in the study.The available documentation on the composition of the relevant intumescent paint coating on solid wood frames differs from source to source, so it was not possible to fully allow for the significance of this.The LCA has not included functional changes in the building linked to load-bearing characteristics, noise, moisture, health or other problems that may result in increased maintenance and replacement. The concrete houses have been dimensioned for 100 years, for instance, in accordance with tried and tested standards and experience. The solid wood house is not dimensioned in the same way, and this has led to us having to assume various scenarios.The results also show the following: • The uncertainties involved in comparing different structures and alternative solutions are very significant. The results are affected by factors such as life cycle, the functional requirements taken into consideration, transportation, design and structural details, etc. • Variations in the built items and a considerable degree of uncertainty in the assumptions make it difficult to obtain significant results on comparisons. Only actual construction projects with known specific data, declared from a life cycle perspective that takes into account actual building developerrequirements and involving different scenarios (best, documented and worst-case) for the user stage can currently be compared. • In the other hand, comparisons restricted to different concrete structures only, or to different timber structures only, ought to involve a lower degree of uncertainty, These would then provide results that are significant as well as improvement requirements that are relevant. • There is potential for improving concrete by imposing requirements on the material • There is potential for improving solid wood frames by developing and guaranteeing well-documented long-term characteristics for all functional requirements. The LCAs were performed as an iterative process where all parties were given the opportunity to submit their viewpoints and suggestions for changes during the course of the work. This helped ensure that all alternatives have been properly thought through.Because, during the project, Riksbyggen opted to procure a concrete frame, in the final stage the researchers involved focused on ensuring the procurement process would result in the concrete frame as built meeting the requirements set out above. As things currently stand, the material requirements for the concrete are limited by the production options open to the suppliers, and this is therefore being investigated in the manufacture of precast concrete frames for the Viva cooperative housing association.
|
|
| 14. |
- Kurkinen, Eva-Lotta, et al.
(författare)
-
Energy and climate-efficient construction systems : Environmental assessment of various frame options for buildings in Brf. Viva
- 2018
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In the collaborative forum Positive footprint housing® Riksbyggen is building the Viva residential quarter, which is a sustainability project at the very forefront of what is possible with contemporary construction. The idea is that this residential quarter should be fully sustainable in ecological, economic and social terms. Since 2013, a number of pilot studies have been completed under the auspices of the Viva project framework thanks to financing from the Swedish Energy Agency. The various building frame alternatives that have been evaluated are precast concrete, cast in-situ concrete and solid wood, all proposed by leading commercial suppliers. The report includes a specific requirement for equivalent functions during the use phase of the building, B. An interpretation has been provided that investigates the building engineering aspects in detail, as well as an account of the results based on the social community requirements specified in Viva, durability, fire, noise and energy consumption in the Swedish National Board of Building, Planning and Housing building regulations (BBR), plus Riksbyggen’s own requirements, Sweden Green Building Council’s Environmental Building Gold (Miljöbyggnad Guld) and 100-year life cycle. Given that the alternatives have different long-term characteristics (and also that our knowledge of these characteristics itself varies), these functional requirements have been addressed by setting up different scenarios in accordance with the EPD standard EN 15978. Because Riksbyggen has specified a requirement for a 100-year life cycle, we have also opted for an analysis period of 100 years. The results show no significant differences between concrete and timber structures for the same functions during the life cycle, either for climate or for primary energy. The minor differences reported are accordingly less than the degree of uncertainty involved in the study. The available documentation on the composition of the relevant intumescent paint coating on solid wood frames differs from source to source, so it was not possible to fully allow for the significance of this. The LCA has not included functional changes in the building linked to load-bearing characteristics, noise, moisture, health or other problems that may result in increased maintenance and replacement. The concrete houses have been dimensioned for 100 years, for instance, in accordance with tried and tested standards and experience. The solid wood house is not dimensioned in the same way, and this has led to us having to assume various scenarios.The results also show the following:• The uncertainties involved in comparing different structures and alternative solutions are very significant. The results are affected by factors such as life cycle, the functional requirements taken into consideration, transportation, design and structural details, etc.• Variations in the built items and a considerable degree of uncertainty in the assumptions make it difficult to obtain significant results on comparisons. Only actual construction projects with known specific data, declared from a life cycle perspective that takes into account actual building developer requirements and involving different scenarios (best, documented and worst-case) for the user stage can currently be compared.• In the other hand, comparisons restricted to different concrete structures only, or to different timber structures only, ought to involve a lower degree of uncertainty. These would then provide results that are significant as well as improvement requirements that are relevant.• There is potential for improving concrete by imposing requirements on the material• There is potential for improving solid wood frames by developing and guaranteeing well-documented long-term characteristics for all functional requirements.The LCAs were performed as an iterative process where all parties were given the opportunity to submit their viewpoints and suggestions for changes during the course of the work. This helped ensure that all alternatives have been properly thought through.Because, during the project, Riksbyggen opted to procure a concrete frame, in the final stage the researchers involved focused on ensuring the procurement process would result in the concrete frame as built meeting the requirements set out above. As things currently stand, the material requirements for the concrete are limited by the production options open to the suppliers, and this is therefore being investigated in the manufacture of precast concrete frames for the Viva cooperative housing association.
|
|
| 15. |
- Kurkinen, Eva-Lotta, et al.
(författare)
-
Kriterier för resurssnålt byggande i praktiken : Slutrapport från forskningsprogrammet E2B2 – energieffektivtbyggande och boende
- 2018
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Arbetet omfattar uppföljning av ställda kriterier för låg klimatpåverkan från betong vid upphandlingav betongstomme för brf. Viva i Göteborg. Kriterierna följdes upp dels genom att LCA studien somgenomförts under programskedet uppdaterades med data för den färdigupphandlade byggnaden ochdels genom att interljuva ett urval av aktörer för att få en inblick över hur branschen ser på de ställdakraven. Arbetet innehåller även en avslutande del angående känsligheten i beräkningarna samtosäkerheter och hur de kan behandlas.Byggnaderna som är tänkta att stå i 100 år kommer utsättas för klimatförändringar. Därförgenomfördes parallellt med LCA studien också energisimuleringar för att se hur den termiskakomforten och uppvärmningsbehovet förändras över tiden.Resultaten av LCA-uppföljningen och de ställda kriterierna visar att kraven uppfylldes för både denprefabricerade betongen och den platsgjutna betongen. Att jämföra den totala klimatpåverkan mellanprogramskedet och upphandlad byggnad visar sig inte vara möjligt då konstruktionen har förändratsalltför mycket, bland annat har den uppvärmda ytan ökat med ca 50% samtidigt som mer material haranvänts för de prefabricerade väggarna och bjälklagen. En känslighetsanalys har istället genomförtssom visar att den upphandlade konstruktionen har 30% lägre klimatpåverkan per BOA jämfört motom den byggts med traditionell betong. Hade de ursprungliga konstruktionsdetaljerna frånprogramskedet använts för väggar och bjälklag hade klimatpåverkan istället varit ca 40% lägre.Vid framtida kravställning bör man därför ta hänsyn även till konstruktionerna, betongkvaliteternaoch dess materialmängder och inte bara ställa krav på betongrecepten som i det här fallet.Klimatsimuleringarna visar att det troligen finns ett stort mörkertal med lågenergilägenheter som harförhöjd temperatur inomhus sommartid redan vid dagens klimat
|
|
| 16. |
- Kurkinen, Eva-Lotta, et al.
(författare)
-
Kriterier för resurssnålt byggande i praktiken
- 2018. - 18
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This work includes monitoring of set criteria for low climate impact from concrete in procurement of concrete structures for brf. Viva in Gothenburg. The criteria were followed up by updating the LCA study performed during the program phase with new data for the completed building, plus a selection of the project stakeholders were also interviewed to gain an insight into how the industry received the set criteria. The work also includes a final sectionregarding the sensitivity of the calculations as well as the uncertainties/error margins and how they can be treated.Buildings that are supposed to last for 100 years will be exposed to climate change, and consequently, parallel to the LCA follow-up, energy simulations were made to see how thermal comfort and heating needs change over time.The results of the LCA follow-up and the set criteria indicate that the requirements were fulfilled for both the prefabricated concrete and the site-cast concrete. Comparing the overall climate impact between the program phase and the procured building was shown not to be possible since the construction has changed too much, for example, the heated surface area has increased by about 50%, while more materials have been used in walls and floor joints, amongst other things. A sensitivity analysis has instead been carried out showing that the contracted construction has 30% lower climate impact per BOA compared to if it was built with traditional concrete. Had the original construction details from the program stage been used for walls and floor joints, the climate impact would have been about 40% lower instead.Therefore, in future requirements, consideration should also be given to the structures and the amount of materials used, and not just to the concrete recipe as is in this case.The climate simulations show that there is probably a large number of unrecorded cases of low energy apartments that have elevated indoor temperatures in summer even in today's climate.
|
|
| 17. |
- Kurkinen, Eva-Lotta, et al.
(författare)
-
Minskar klimatpåverkan under byggprocessen genom att ställa tydliga krav.
- 2017
-
Ingår i: Bygg och Teknik. - Sweden : Bygg och Teknik. ; 5
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Minska klimatpåverkan under byggprocessen genom att ställa tydliga krav. Att ställa krav på materialleverantörer har stor potential till minskad klimatpåverkan under byggprocessen och triggar utvecklingen av mer klimatsmarta produkter. I pilotprojektet Brf. Viva har Riksbyggen ställt krav på sammansättningen och produktionen av betong. Kraven har sitt ursprung i LCA analyser som utförts som beslutsunderlag för valet av stomme.
|
|
| 18. |
|
|
| 19. |
- Suchorzewski, Jan, et al.
(författare)
-
Concrete mix design for tidal turbine foundation
- 2021
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Sabella D10 tidal turbine was immersed in the Fromveur Strait in June 2015 and became the first, and at the time only, grid-connected full scale marine current turbine (MCT) in France. However, the future of MCT industrial projects lies in lowering the levelized cost of electricity (LCOE). Evaluating new possibilities to design a competitive foundation will be a key issue for the future commercial development of SABELLA’s technology. The purpose of CF2T project is to develop a competitive foundation, immerse it as part of a precommercial project and validate the concept in real sea environment. The innovative foundation was designed to decrease construction costs, with modular interfaces to allow an installation in several packages (foundation parts, ballasts, turbine) in order to limit the installation vessel’s crane capacity requirement, which will also reduce installation costs. A concrete foundation with steel footings and turbine bed were considered to lower the manufacturing costs and increase the foundation durability comparing to currently used steel foundations. RISE Infrastructure and Concrete Technology supported the process of concrete material selection and casting technology. The material design was preceded with numerical analysis of early cracking due to hydration heat development, which indicated that there exists a substantial risk of thermal cracking. Three different variants of concrete mixes complying the design strength and stiffness criteria with low hydration heat were developed concerning various available casting technologies. The mixes were tested for standard concrete properties: compressive and flexural strength, modulus of elasticity, consistency, and shrinkage. The selected materials were submitted to accelerated durability testing including shrinkage and chloride migration. A basic life cycle analysis (LCA) of the concrete material, manufacturing was performed and compared to steel foundation solution to assess the sustainability of the designed structural and material solutions. The innovative concrete foundation and traditional steel foundation with D14 turbines are meant to be monitored with a specially developed sensors and data acquisition system in real sea environment.
|
|
