Jämförelse mellan en träbro och en betongbro : En LCA-analys med fokus på koldioxidutsläpp samt en LCC-analys

This report is a thesis for collegeengineering program in structuralengineering at Uppsala University andwas commissioned by the Swedishcontractor Svevia. The study aims toprovide an overview of the mostbeneficial bridge material from bothenvironmental and economic point ofview.The life-cycle analysis covers onlycarbon dioxide emissions, since it isthe most spoken of in today’s climateagenda. Furthermore, this study aims tohighlight which parts, of the systemboundary, that contributes to greatercarbon emissions for the wood- and theconcrete bridge.The life-cycle cost analysis wascalculated with a lifespan of 40 yearsand covers the basic cost of investment,operating and maintenance, anddecommissioning costs.The analyzed constructions in this studyare existing projects that are almostcompleted. Both bridges were designed tohandle loads up to 60 tons. The woodenbridge is a precast cross tense flatbridge while the concrete bridge is anin situ frame bridge.Since the analyzed constructions in thisstudy differ from each other, theresults are presented both as individualbridges and as a comparison studybetween wood and concrete material inwhich the functional unit is set tokgCO2 and kgCO2/unit area. To give thereader a clearer picture of thedifferences in carbon dioxide emissionsan additional calculation was done, withan adopted traffic area of 144m2 forboth the wooden bridge and the concretebridge.For the life cycle cost estimation, thebridges’ individual results and acomparative analysis were done. For thecomparative analysis between the woodenand the concrete bridge a common trafficarea of 144 m2 was adopted.