Climate Change Mitigation Measures of Load-Bearing Structure - A comparison of alternative structural designs using Life Cycle Assessment
(2020) In TVBK-5275 VBKM01 20201Division of Structural Engineering
- Abstract (Swedish)
- I mars 2015 nådde den globalt genomsnittliga koldioxidhalten 400 ppm för första gången på tre miljoner år. Därför satte den svenska regeringen, år 2017, upp målet att Sverige ska vara klimatneutralt år 2045. Samtidigt står den svenska byggindustrin för 18,1 miljoner ton växthusgasutsläpp, vilket motsvarar 19 procent av Sveriges totala utsläpp.
Syftet med denna studie är att undersöka och analysera hur växthusgasutsläpp påverkas av byggnadsstommens spännvidder, tvärsnitt och gjutmetod med hjälp av Livscykelanalys (LCA), samt att bedöma vilken av byggprocesserna som står för störst andel växthusgasutsläpp. En fullständig LCA har utförts på tjugo olika stomalternativ med identiska lastfall för Telias kontorsbyggnad i Malmö, Sverige.
... (More) - I mars 2015 nådde den globalt genomsnittliga koldioxidhalten 400 ppm för första gången på tre miljoner år. Därför satte den svenska regeringen, år 2017, upp målet att Sverige ska vara klimatneutralt år 2045. Samtidigt står den svenska byggindustrin för 18,1 miljoner ton växthusgasutsläpp, vilket motsvarar 19 procent av Sveriges totala utsläpp.
Syftet med denna studie är att undersöka och analysera hur växthusgasutsläpp påverkas av byggnadsstommens spännvidder, tvärsnitt och gjutmetod med hjälp av Livscykelanalys (LCA), samt att bedöma vilken av byggprocesserna som står för störst andel växthusgasutsläpp. En fullständig LCA har utförts på tjugo olika stomalternativ med identiska lastfall för Telias kontorsbyggnad i Malmö, Sverige.
Handberäkningar, som följer Eurokod, har utförts i denna studie för att beräkna mängden stål och betong för respektive stomme. Beräkningsprogrammet FEM Design har använts för att verifiera och jämföra resultaten från handberäkningarna.
I Livscykelanalysen inkluderas processer från vaggan till graven; råvaruförsörjning och tillverkning, transporter till byggplats, bygg och installation, karbonatisering, rivning, avfallshantering och återvinning. Studien har exkluderat funktionella förändringar av stommen kopplat till brand, ljud, fukt och hälsa. Processer såsom underhåll, reparation, utbyte, ombyggnad samt energi och vattenanvändning har ej inkluderats. Livslängden för stommen har antagits till 100 år och den valda miljöpåverkanskategorin är global uppvärmningspotential.
Resultaten visar att produktskedet står för 77–81% av stommens totala globala uppvärmningspotential. Ett tunt tvärsnitt för ett platsgjutet bjälklag resulterar i en lägre miljöpåverkan tills bjälklaget blir alltför tunt och både mängden armering och växthusgasutsläppen ökar då drastiskt. En ökad spännvidd för ett platsgjutet bjälklag ger en lägre global uppvärmningspotential fram till spännvidden ökat alltför mycket då mängden armering ökar drastiskt och därmed den globala uppvärmningspotentialen. Slutligen visar resultaten att den optimala designen i detta fall är ett håldäcksbjälklag med en 8-meters spännvidd som står för 135 kg CO2e/m2Atemp; en minskning på 18% gentemot ursprungsutförandet. (Less) - Abstract
- The global average carbon dioxide concentration reached 400 ppm for the first time in three million years, in March 2015. This calls for drastic measures so in 2017 the Swedish government set up the goal of making Sweden climate neutral by 2045. Meanwhile, the construction sector in Sweden accounts for 18.1 million tons of green- house gases which is 19 percent of Sweden’s total emissions.
The purpose of this study is to investigate and analyze how greenhouse gas emissions are impacted by the load-bearing structures span length, cross-section and concrete casting method for load-bearing structures using Life Cycle Assessment (LCA). Further- more, to evaluate which process throughout the load-bearing structure’s lifetime is dominant in... (More) - The global average carbon dioxide concentration reached 400 ppm for the first time in three million years, in March 2015. This calls for drastic measures so in 2017 the Swedish government set up the goal of making Sweden climate neutral by 2045. Meanwhile, the construction sector in Sweden accounts for 18.1 million tons of green- house gases which is 19 percent of Sweden’s total emissions.
The purpose of this study is to investigate and analyze how greenhouse gas emissions are impacted by the load-bearing structures span length, cross-section and concrete casting method for load-bearing structures using Life Cycle Assessment (LCA). Further- more, to evaluate which process throughout the load-bearing structure’s lifetime is dominant in greenhouse gas emissions. A full LCA has been conducted on twenty different load-bearing structures with identical load cases for the Telia office building in Malm ̈o, Sweden.
Hand calculations, following Eurocode, have been performed in this study in order to calculate all steel and concrete quantities for each alternative design. The software program FEM Design was utilized to verify and compare with results from the hand calculations.
The Life Cycle Assessment includes processes from cradle-to-grave; raw material extraction and manufacturing, transportation to construction site, installation and construction, carbonation, demolition, waste processing and disposal. The study has excluded functional changes of the load-bearing structure related to fire, acoustics, moisture and health. Additionally, no processes like maintenance, repair, replacement, refurbishment and energy and water use were included. The lifespan of the load-bearing structure has been assumed to 100 years with the focus on global warming potential.
The results from the study show that the product stage accounts for 77-81% of the total global warming potential of the load-bearing structure. A more slenderer cross-section for an in-situ concrete slab results in a lower environmental impact until a breaking point where the reinforcement steel and the greenhouse gas emission increases rapidly. Similar to the cross-section, an increased span length for an in-situ concrete slab reduces the global warming potential until the span length has increased excessively and the reinforcement steel quantity and global warming potential increases dramatically. Finally, the results conclude that the optimal alternative design in this case is a hollow-core slab with an 8-meters span length which accounted for 135 kg CO2e/m2Atemp; an 18% reduction compared to the original design. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9014716
- author
- Jalil, Mirass LU
- supervisor
- organization
- alternative title
- Åtgärder för att begränsa klimatpåverkan från byggnadsstomme - En jämförelse mellan stomalternativ med Livscykelanalys
- course
- VBKM01 20201
- year
- 2020
- type
- H3 - Professional qualifications (4 Years - )
- subject
- keywords
- Life Cycle Assessment, LCA, Load-Bearing Structure, Livscykelanalys, Byggnadsstomme, stomalternativ, structural engineering, span length, cross-section depth, precast concrete slab, in-situ concrete slab.
- publication/series
- TVBK-5275
- report number
- TVBK-5275
- ISSN
- 0349-4969
- language
- English
- additional info
- Examinator: Eva Frühwald Hansson
- id
- 9014716
- date added to LUP
- 2020-06-09 08:30:03
- date last changed
- 2020-06-15 16:33:30
@misc{9014716,
abstract = {{The global average carbon dioxide concentration reached 400 ppm for the first time in three million years, in March 2015. This calls for drastic measures so in 2017 the Swedish government set up the goal of making Sweden climate neutral by 2045. Meanwhile, the construction sector in Sweden accounts for 18.1 million tons of green- house gases which is 19 percent of Sweden’s total emissions.
The purpose of this study is to investigate and analyze how greenhouse gas emissions are impacted by the load-bearing structures span length, cross-section and concrete casting method for load-bearing structures using Life Cycle Assessment (LCA). Further- more, to evaluate which process throughout the load-bearing structure’s lifetime is dominant in greenhouse gas emissions. A full LCA has been conducted on twenty different load-bearing structures with identical load cases for the Telia office building in Malm ̈o, Sweden.
Hand calculations, following Eurocode, have been performed in this study in order to calculate all steel and concrete quantities for each alternative design. The software program FEM Design was utilized to verify and compare with results from the hand calculations.
The Life Cycle Assessment includes processes from cradle-to-grave; raw material extraction and manufacturing, transportation to construction site, installation and construction, carbonation, demolition, waste processing and disposal. The study has excluded functional changes of the load-bearing structure related to fire, acoustics, moisture and health. Additionally, no processes like maintenance, repair, replacement, refurbishment and energy and water use were included. The lifespan of the load-bearing structure has been assumed to 100 years with the focus on global warming potential.
The results from the study show that the product stage accounts for 77-81% of the total global warming potential of the load-bearing structure. A more slenderer cross-section for an in-situ concrete slab results in a lower environmental impact until a breaking point where the reinforcement steel and the greenhouse gas emission increases rapidly. Similar to the cross-section, an increased span length for an in-situ concrete slab reduces the global warming potential until the span length has increased excessively and the reinforcement steel quantity and global warming potential increases dramatically. Finally, the results conclude that the optimal alternative design in this case is a hollow-core slab with an 8-meters span length which accounted for 135 kg CO2e/m2Atemp; an 18% reduction compared to the original design.}},
author = {{Jalil, Mirass}},
issn = {{0349-4969}},
language = {{eng}},
note = {{Student Paper}},
series = {{TVBK-5275}},
title = {{Climate Change Mitigation Measures of Load-Bearing Structure - A comparison of alternative structural designs using Life Cycle Assessment}},
year = {{2020}},
}