This research includes a preliminary study prior to the commencement of the Ph.D. work and three phases of design, construction and testing of three generations of moment-shaped beams. Each phase of the research brought a better understanding of curved beams which follow the shape of the moment diagram. The moment diagram in this study was for simply supported beams supporting a uniformly distributed load as would be the case in the majority of building designs. The original theory for this research can be described as follows: Moment-shaped beams are the natural outcome of a fundamental understanding of stress paths in a horizontal load bearing member. By following these stress paths we may provide materials where required to most efficiently carry the compression and tension stresses to the supports. Allowing stresses to follow their naturally desired paths reduces regions where stresses cross paths called disturbed regions. The outcome of the final phase of this research was the development of the third generation of curved beams with a camber. These beams, designated as Cambered Curve beams (CCBs), exhibited the same behaviour as the rectangular control beam design using CSA-A23.3 up to the serviceability failure of L/360 (12mm). The CCB moment-shaped beams require 20% less concrete and 40% less reinforcing steel (no shear stirrups) to carry the ultimate load which is only 12% less than that carried by the CSA-designed control beam. Due to a closed system of internal forces, the moment-shaped beams remain intact and are able to sustain self weight, even after total failure. A significant part of this research was to modify and verify a FORTRAN-based finite element analysis program: FINIT-Y. This program was reconstructed to analyse a full size beam, and enabled the researcher to model and correctly predict the maximum load, crack pattern and failure mode. This study found that moment-shaped beams with no shear reinforcement have the same stiffness and load carrying capacity as the CSA-designed rectangular control beam with shear reinforcement up to serviceability failure (L/360). The study also found that moment-shaped beams have significantly lower ductility at the ultimate load.

This research includes a preliminary study prior to the commencement of the Ph.D. work and three phases of design, construction and testing of three generations of moment-shaped beams. Each phase of the research brought a better understanding of curved beams which follow the shape of the moment diagram. The moment diagram in this study was for simply supported beams supporting a uniformly distributed load as would be the case in the majority of building designs. The original theory for this research can be described as follows: Moment-shaped beams are the natural outcome of a fundamental understanding of stress paths in a horizontal load bearing member. By following these stress paths we may provide materials where required to most efficiently carry the compression and tension stresses to the supports. Allowing stresses to follow their naturally desired paths reduces regions where stresses cross paths called disturbed regions. The outcome of the final phase of this research was the development of the third generation of curved beams with a camber. These beams, designated as Cambered Curve beams (CCBs), exhibited the same behaviour as the rectangular control beam design using CSA-A23.3 up to the serviceability failure of L/360 (12mm). The CCB moment-shaped beams require 20% less concrete and 40% less reinforcing steel (no shear stirrups) to carry the ultimate load which is only 12% less than that carried by the CSA-designed control beam. Due to a closed system of internal forces, the moment-shaped beams remain intact and are able to sustain self weight, even after total failure. A significant part of this research was to modify and verify a FORTRAN-based finite element analysis program: FINIT-Y. This program was reconstructed to analyse a full size beam, and enabled the researcher to model and correctly predict the maximum load, crack pattern and failure mode. This study found that moment-shaped beams with no shear reinforcement have the same stiffness and load carrying capacity as the CSA-designed rectangular control beam with shear reinforcement up to serviceability failure (L/360). The study also found that moment-shaped beams have significantly lower ductility at the ultimate load.

Life Cycle Assessment (LCA) is the globally the most recognised method for quantifying theimpact the a product or service has on the environment through its whole life-span. Theconstruction sector plays a key role in the depletion of the natural resources and the energyconsumption on the planet. Thus it is fundamental that an environmental assessment tool likeLCA should be in close cooperation with the construction process.This thesis focuses on the environmental impact of bridge abutments, and can be divided in twoparts.The rst one focuses on enhancing the automated design in the construction eld. A Python codeis created that focuses on creating the geometry of any type of bridge abutment and conductingthe calculations for the required concrete and reinforcement. The process is attempted to becomecompletely automated.The second part introduces three alternative designs for a bridge abutment that attempt to havethe same structural properties and cooperate successfully with the superstructure, while at thesame time utilize as little material as possible. The possible reduction in material is quantiedin environmental terms after an environmental impact assessment is performed.The results show that dierent designs can have a great impact on the reduction on the materialconsumption and on the impact that the whole structure has on the environment. The resultsin this study might provide the designers with valuable motivation and guidelines to achievehigher sustainability standards in the future.

Genom fluglarvskompostering erhålls biomassa från organiskt avfall samt en näringsrik behandlingsrest som kan användas som gödningsmedel eller för biogasutvinning. Larvbiomassan kan användas som djurfoder eller för att tillverka biodiesel. Eskilstuna Strängnäs Energi och Miljö AB planerar bygga en pilotanläggning för fluglarvskompostering med larver av den amerikanska vapenflugan (Hermetia illucens). Behandlingen ska ske i lådor staplade på varandra, avskilda med ett mellanrum för att tillåta luftning av materialet. Luftningsbehovet utgörs av larvernas syrebehov samt av att transportera bort fukt och värme från materialet. Syftet med det här projektet var att utvärdera luftningsbehovet under fluglarvskomposteringsbehandling av matavfall med staplade behandlingslådor. Först designades ett experimentskåp att utföra experimenten i och därefter ett ventilationssystem till skåpet. Två experiment utfördes där tre staplar med nio behandlingslådor vardera utvärderades. I experiment I användes totalt 15 kg matavfall och 15 000 larver per behandlingslåda, i experiment II användes 11 kg matavfall och 10 000 larver per behandlingslåda. Under experimenten togs prover för torrsubstans (TS) och glödförlust (VS), pH samt tillväxt av larverna. Sensorer mätte lufttemperatur, relativ luftfuktighet och materialtemperatur. I båda experimenten erhölls en behandlingsrest med betydligt lägre TS-halt än önskat, vilket troligtvis berodde på att luftflödet i experimentskåpet var lägre än beräknat. I experiment I evaporerade i genomsnitt 6,2 kg vatten per behandlingslåda och i experiment II 4,8 kg, vilket för båda experimenten motsvarade cirka 50 % av det med matavfallet tillsatta vattnet. Enligt resultaten av experimenten kan torrsubstansen av matavfallet reduceras med runt 60 %. Runt 32 % av torrsubstansen i matavfallet omvandlades till larvbiomassa. Materialtemperaturen var i genomsnitt 27–30 °C under experimenten. Lufttemperaturen i experimentskåpet var 27–28 °C och 31 °C i inluften. Den relativa luftfuktigheten i experimentskåpet var 59–67 % och 36 % i inluften. Baserat på resultaten krävs ett luftflöde på 8,4 m3/h per behandlingslåda för att nå en TS på 50 % i behandlingsresten om matavfallet har en TS-halt på 15 %. Baserat på resultaten är ett nedåtriktat luftflöde att föredra framför uppåtriktat i de fall ett vertikalt luftflöde används. Skillnader i temperaturer och luftfuktighet indikerade dock att det vertikala, nedåtriktade, luftflödet inte kunde förse alla behandlingslådor i staplarna med samma luftflöde. På grund av detta kan det vara lämpligt att överväga ett horisontellt luftflöde i containern i vilken behandlingen ska ske. Vidare kan det vara fördelaktigt att reglera vattenhalten i matavfallet så att stora variationer i luftningsbehov undviks eller reglera luftflödet efter vattenhalt i ingående matavfall. Inför val av ventilationsdesign rekommenderas fortsatta studier av hur höga luftflöden påverkar behandlingen. / Larvae of the Black Soldier Fly (Hermetia illucens) can convert organic waste into biomass. The residue is nutrient-rich and can be used as fertilizer or for biogas production. The aim of this study was to assess the aeration need for designing a ventilation system in a pilot plant for larvae composting in Sweden. First, a cabinet with required ventilation arrangement for performing the experiments was designed. Two experiments were performed, where three stacks each comprised of nine boxes with spacers were used. In the first experiment, a total of 15 kg of municipal food waste and 15 000 larvae were used per box. In the second experiment, a total of 11 kg food waste and 10 000 larvae were used per box. In the first experiment 6.2 kg of water evaporated per treatment box and in the second 4.8 kg, both corresponding to about 50 % of the water present in the substrate added. An average temperature of 31 °C in the inlet air resulted in temperatures of 27-30 °C in the material during the treatment. Based on the results, 8.4 m3/h of air is needed per treatment box to reach 50 % dry matter in the residue of food waste containing 15 % dry matter. The results also indicate that to reach the desired water content in the residue, there might be a need to adjust the initial water content in the food waste and use horizontal airflow in the treatment container. Before deciding on a ventilation design, further studies are necessary to assess how high airflows affect the treatment.

Behovet av bättre avfallshantering ökar ständigt då befolkningen ökar och jordbruket intensifieras. Avfallshanteringen idag är dåligt konstruerad för organiskt avfall i många länder då det hamnar på deponier som släpper ut växthusgaser till atmosfären vilket påverkar klimatet negativt. En möjlig lösning att implementera en metod som genererar en värdefull produkt så som fluglarvskompostering. Det är en organisk avfallsbehandlingsmetod som använder larver av den amerikanska vapenflugan som kan reducera mängden avfall. Avfallet omvandlas till larvernas biomassa som är proteinrik och kan användas som djurfoder. Behandlingsresterna kan användas som gödningsmedel eller producera biogas. Väldigt lite är känt gällande växthusgasutsläppen från fluglarvskompostering. Under nuvarande EU lagstiftning i produktionssammanhang så är flugan ett produktionsdjur, som inte tillåts att födas upp på matavfall innehållande animaliska biprodukter. Därför har vegetabiliskt matavfall undersökts i denna studie för att i produktionssammanhang kunna använda sig av fluglarvskompostering. De vegetabiliska avfallet som använts var apelsinskal och blomkål blandat med broccoli (i denna studie kallad blomkålsblandning). Vegetabiliskt avfall innehåller svåråtkomlig näring för larverna och för att de ska kunna tillgodose sig så mycket som möjligt gjordes förbehandlingar. Förbehandlingarna som utfördes var med svamp och med ammoniumlösning då dessa har visat sig spjälka upp svåråtkomlig näring. Matavfall är känt för att fungera bra i fluglarvskompostering och användes som referens. Utsläpp av växthusgaserna CO2, NH3, N2O och CH4 undersöktes genom användande av kammarteknik. Vid behandlingar av blomkålsblandningen förbättrade förbehandlingarna materialreduktionen endast lite, vilket var i genomsnitt 82 %, men den totala minskningen i detta substrat var större än för matavfall vars reduktion var 60 %. Reduktionen varierade mellan 38-86 % i behandlingarna av apelsinskal. Larvbehandlingen av matavfall resulterade i den högsta omvandlingskvoten. Båda vegetabiliska substraten förbehandlat med NH4+ hade höga utsläpp av NH3. Behandlingarna av blomkålsblandningen hade högre utsläpp av N2O men mindre än i konventionella avfallsbehandlingar som kompostering. De substrat som inte förbehandlats hade låga utsläpp av CH4, inklusive matavfallet jämfört med de förbehandlade substraten som var mindre än i aerobisk kompostering. När en behandlingsstrategi väljs för kompostering med fluglarver, för små gasutsläpp så bör svampförbehandlat substrat användas, medan substrat förbehandlat med NH4+ resulterar i högre materialreduktion. / The need for better waste management is increasing as the population increases and agriculture is intensified. Organic waste management today is poorly designed in many countries leading to waste ending up in landfills which results in more greenhouse gases being emitted to the atmosphere, contributing to the global climate change. A possible solution is to implement a method that generates a valuable product such as fly larvae composting, which is an organic waste treatment method that uses larvae of the black soldier fly that can reduce the amount of waste. The waste is converted to the larval biomass which is rich in protein and possible to use as animal feed. Treatment residues can be used as fertilizers or to produce biogas. Very little is known about greenhouse gas emissions from fly larvae composting. Under current EU legislation in production contexts, the fly is considered a production animal that is not allowed to be raised on food waste containing animal by-products. Therefore, in this study, vegetable waste was investigated in order to be able to use fly larvae composting in production contexts. The vegetable waste used was orange peels and cauliflower mixed with broccoli (in this study referred to as cauliflower mix). Vegetable waste contains nutrients which are hard to digest for larvae and in order to improve digestibility, pretreatments were performed. The pretreatments carried out were with fungus and ammonia solution, as these have been shown to make hardly bound nutrients available. Food waste is known to work well in fly larvae composting and was used as a reference. Emissions of greenhouse gases CO2, NH3, N2O and CH4 were measured using chamber technique. In the treatment of cauliflower mix, the pretreatment improved the material reduction only slightly, which was on average 82 % but the overall total reduction was greater than that for food waste which had a reduction at 60 %. The reduction ranged between 38-86 % among all of the treatments of orange peels. Larvae treatment on food waste resulted in the largest biomass conversion ratio. Both vegetable substrates pretreated with NH4+ had high emissions of NH3. The treatments of cauliflower mix had higher emissions of N2O but they were lower than what is generally expected in conventional waste treatments such as composting. The non-pretreated substrates had low emissions of CH4, including the food waste compared to the pretreated ones which nevertheless were lower than in aerobic composting. When selecting a treatment strategy for fly larvae composting, to achieve low gas emissions, fungus pretreated substrates should be used while substrates pretreated with NH4+ result in higher material reduction.