As the material consumption has been decreased through optimisation it will likely also decrease the overall cost of the structure. The economical advantages of optimising a structure has earlier been proved for both steel [Sahab et al., 2005] and concrete [Jármai and Farkas, 1999] and is assumed to be the same for wood structures.
By implementing increased knowledge in the early design stage through coopo-ration between engineers and architects it would be possible to improve the overall environmental and economical sustainability of a structure. It would give the architects the possibility to consider different solutions and materials based on analysis in the early design stage. Though it would only be of use where architects and engineers work together during the design stage, thus only relevant for larger projects or larger companies with the resources in-house.
Commisioning and legislation would be one way to increase the awareness on the possibilities with optimisation in the early design stage. The early design stage often lack financial basis as many designs are put out for competition.
For the achitectural companies the balance of both economical investments and investment of time is determining for this process of giving a proposal. The case study used throughout this study was ideal as the competition was completed and the time to construction was more than a year. By investing more time and money through this initial design stage, optimisations are possible and the program modelled could help the decision making throughout this process.
Furthermore would it be possible to use the optimisation as marketing the struc-ture as the saving of material could be converted into saved CO2 which is an understandable term for the broader population.
Today it is possible to built forms regardless of their structural performance [Mueller and Ochsendorf, 2013], whitout consulting the effectiveness of the struc-ture giving the best structural performance material-wise.
Chapter 7
Conclusion
The main thesis of this report was verified for the specific case, Konsthall Tornedalen, as it proved possible to reduce the environmental impact of the structure, through a dynamic real-time integrated deisgn process carried out via the parametrical modelling tool Grasshopper.
A limited empirical investigation of the programs used in the industry directed the choice of program towards using Rhino with the plug-ins Grasshopper and Karamba. The already existing programs that are widely spread in the industry proved capable of facilitating a dynamic design process. A futher advantage of the parametric design program was its visual programming platform allowing instant result outputs during the design process.
The tailor made structural design model created for the Konsthall Tornedalen in Grasshopper permitted a real-time reduction of the material consumption.
The parametric design in Grasshopper allowed for extensive investigation of the structural design with result visualisations in Rhino and exports to Microsoft Excel.
Quantitative decision making was possible and an optimisation of the structure, faithful to the initial design was suggested through six optimisation steps. The six steps including investigation of heights, cross sections, materials, sequencing of the structure, change of angles and distances resulted in a reduction of the
material consumption for steel by 74.3% and for wood by 68.9%.
The clear reduction in material consumption could provide a basis for discussion and collaboration between construction engineers and architects. By parame-terising the model in Grasshopper, the model allows for expansion and further development as the design process progresses. Further requirements and criteria can be incorporated upon request from the design team. Parametric program-ming in Grasshopper could advantageously be used in the industry to gain in-stant knowledge of the optimisation possibilities of a structure. The integration of the structural input gained from the real-time model in Grasshopper has the potential to improve the initial concept significantly.
It is the experience that the model once created can facilitate a dynamic real-time design process involving the architects. The process of developing a pro-gram suitable for a given structure will increase in effectiveness as the engineer or architect gain experience. Initially it can be time consuming and involve pioneering work, but as more projects are investigated the executing designer will gain more knowledge and an increased understanding of the software and its possibilities.
It proved possible to use the existing LCA tool Quantis Suite during the pre-liminary design process in order to document the environmental impacts of the building on-the-fly. The results from Quantis Suite showed that the design tool focusing on optimising the mass of the structure was sufficient and relevant in the early design process. This is supported by the fact that there is an extensive correlation between the mass consumption and the environmental impact.
The life cycle assessment comparisons of the initial raw structure and the final structure, confirmed that by optimising the material efficiency, a more envi-ronmental friendly structure can be designed. The steel structure reduced all five impact categories by around 70% from the initial design to the final design whereas the wooden structure had a reduction of approximetaly 48% in all five impact categories.
Quantis Suite was also used to test the environmental impact from the roof and it was found that building parts with shorter lifespans count heavily in the total calculation of the environmental impact of the building.
An exact LCA is close to impossible to make due to the many uncertainties associated with the life cycle process. It was clear that further optimisation possibilites exist for the building envelope, both in terms of material and the lifespan of the building parts.
The reduction of the material consumption is assumed to be correlated with a
82
reduced prize of the building. In this way the use of these tools will offer the designers additional space for creative solutions in the design of the building within a given budget.
7.0.1 Further Studies & Perspectives
The experience gained through this project provides relevant information for the industry as an optimisation of the structural design and hereby reduction of the environmental impacts has been proved. Through pioneer projects in the industry the increase of public awareness and life cycle thinking in the early structural design stage can be promoted and tested, creating a basis for a more sustainable building industry in the future. Possible economical savings due to material savings and early design decision making could be of interest to a low margin industry.
As the programs and software continue to develop the linking possibilities of the programs will increase in the future, allowing a broader and more efficient collaboration between engineers and architects.
Another way to realise structural optimisation integrated in the early design stage is through legislation. This could either be through legislation of public building projects or by announcing future requirements for early design focus on the life cycle of a building and its environmental impact. The legislation would enhance a better resource utilization and promote a new aestheticism, as the life cycle thinking becomes a part of the building industry. Public building projects have already begun to impose themselves with requirements of DGNB certificates in order to improve their profile. The DGNB certificate is granted after the project phase as all the material components and other impacts on the environment must be included, thus is the DGNB not necessarily enhancing the sustainability of a project in the conceptual design phase.
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• Appendix A: Mail correspondence, Vandkunsten
• Appendix B: Mail correspondence, OOPEAA
• Appendix C: Case Konsthall Tornedalen
• Appendix D: Load Calculations
• Appendix E: Steel Optimisation Step 1.
• Appendix F: Wood Optimisation Step 1.
• Appendix G: Roof Structure
• Appendix H: Steel Optimisation Step 2.
• Appendix I: Wood Optimisation Step 2.
• Appendix J: Steel Optimisation Step 3.
• Appendix K: Wood Optimisation Step 3.
• Appendix L: Steel Optimisation Step 4.
• Appendix M: Wood Optimisation Step 4.
• Appendix N: Steel Optimisation Step 5.
• Appendix O: Wood Optimisation Step 5.
• Appendix P: Steel Optimisation Step 6.
• Appendix Q: Wood Optimisation Step 6.
ii
• Appendix R: FEM-Design Check
• Appendix S: Electricity During Construction
• Appendix T: LCA Quantities Steel & Wood
• Appendix U: Simple GWP Calculation for Steel & Wood
Mailkorrespondance med Vandkunsten siden April 2014 From: Jak@vandkunst.dk
To: chris_collin@hotmail.com Subject: SV: Speciale - LCA
Date: Tue, 23 Feb 2016 09:04:03 +0000
Hej Christine, Godt at høre fra dig ;)
Og ja, det er stadigvæk korrekt. Men jeg kan se at vi kommer til at anvende revit tidligere i designfasen fremover til og med at revit nu giver mulighed for udvidede analyser (project vasari er jo endt, men autodesk er i gang med at lancere forskellige plugins til revit som vil give mulighed for sol- og vind analyser direkte fra revit, og ellers prøver vi at anvende mulighederne til mængdeudtræk fra revit i større omfang for at kunne lave hurtige LCA og LCC vurderinger fremover).
Mange hilsner, Jan
jan schipull kauschen arkitekt maa, ph.d.
vandkunsten // krudtløbsvej 14 / dk-1439 københavn k / www.vandkunsten.com / +45 6040 2785
Fra: Christine Collin [mailto:chris_collin@hotmail.com]
Sendt: 18. februar 2016 12:31 Til: Jan Kauschen <Jak@vandkunst.dk>
Emne: RE: SV: Speciale - LCA
Hej Jan
Vi har tidligere kommunikeret ang. et speciale, da Vandkunsten er en del af Nordic Built projektet. Jeg endte dog med et samarbejde med OOPEAA gennem Lotte Bjerregard på instituttet for BYG på DTU, da de havde et projekt relevant for konstruktionsoptimering i den tidlige design fase.
Jeg vil gerne sige tak for dine inputs tidligere da det altid er til stor nytte at høre hvad der rører sig i industrien.
Igennem arbejdet til mit bachelor project interviewede jeg Søren Nielsen ang.
jeres arbejde i 2013 (bl.a. Tanghuset) om jeres anvendelse af programmer og ville høre om de udsagn stadig passer eller om I kan tilføje noget nyt.
Appendix A: Mail correspondence, Vandkunsten
Jeg har noteret at I har brugt følgende programmer:
Tidlig design fase: Håndtegning/skitsering, Google SketchUp, AutoCAD, Rhino Projektering: AutoCAD, Revit
"Søren Nielsen from Vandkunsten emphasized the increasing demand for maneuvering many different programs as the programs develop and supplement each other or work as plug-ins in relation to each other.
He saw the possibilities for implementing new parameters in the initial design stage as on the fly life cycle analysis (LCA) as highly useful."
De bedste hilsner Christine Collin
From: Jak@vandkunst.dk
To: chris_collin@hotmail.com Subject: SV: Speciale - LCA
Date: Tue, 28 Oct 2014 13:39:56 +0000
Hej Christine,
Det lyder som et spændende arbejde du skal kaste dig ud i ;)
Der er faktisk temmelige mange ”løse ender” med hensyn til anvendelse af LCA, byggeriet og anvendelse på tegnestuer.
Pt har vi en lidt ”paradoxal” situation at LCA endnu ikke er en øvelse som skaber værdi hos nogen (undtagen samfundet) – og dermed heller ikke er en
fakturerbar ydelse endnu. Jeg tror fast på at det ændrer sig om lidt, men for nu sætter det sådan set rammerne omkring anvendelsen.
Med DGNB er der kommet meget fokus på emnet, men anvendelsesmulighederne og det værktøj som skal anvendes begrænser meget hvad der kan ”læres” af disse LCA’er.
Mere generelt kan man sige at tegnestuer mangler et godt værktøj som tillader
”optimering” af konstruktioner, facadeløsning og giver støtte til materialevalg i alt mulige sammenhæng. Her bliver det lidt relevant at lære at man ikke kan sammenligne de data man finder i en database eller EPD direkte, men at de skal
”bindes op” på en funktion.
I de LCA’er jeg selv har lavet kunne jeg mærke at det især var LCI-fasen som har kostet utrolig meget tid – dette er i princippet en grund til at tegnestuer ikke kan gennemføre mere nøjagtige LCA’er, enten fordi der er for omkostningsfuld (mange timer) eller at det tager for lang tid for at kunne anvendes i de tidelige faser (konkurrencer varer typisk kun få uger). Så her ligger bestemt en del
de her punkter, og vi har også en del konkrete projekter som du vil kunne bruge som cases vil jeg mene).
Et andet stor ”gab” er brugsfasen, her findes ingen generiske LCA-data, udover energiforbrug i driften og ”udskiftninger”. Det kunne dog være yderst interessant at lære mere om forskellige konstruktioner, og det krævede vedligeholdelse hvad angår tilførelse af sekundære materialer og arbejdsindsatsen, men også miljøpåvirkninger som opstår i anvendelsen (f.eks. kunne jeg lære at
tanginddækningen på tanghuset ”oxiderede” løbende som medfører en konstant udledning af CO2 fra taginddækningen).
Ellers findes der en hel del spørgsmål omkring End-of-Life og det forholdsvis begrænsede antal af scenarier vi har pt. Her var det ønskelig at man udviklede en slags metode til at tilgodese genanvendelse og en form for vægtning som vil prioritere genanvendelse på ”højere” niveauer, for at udskyde recycling tidsmæssigt (som igen vil reducere miljøpåvirkninger. Projekter som Upcycle – House har dertil anvendt en metode som bygger på den økonomiske værdi ting har – det er vist ok rent metodisk – fra mit synspunkt bliver der dog ikke taget nok hensyn til miljøpåvirkningerne som kunne undgås hvis disse materialer blev tilført en anden materialekredsløb (som eksempel kan du tage stålcontainere, som nu er huset bærende konstruktion – i stedt kunne man have anvendt nyt (eller også gammelt) træ og tilført containeren en recyclingkredsløb hvor den erstatter ny-produktionen af stål. Uden at jeg har regnet på det vil jeg mene det miljømæssigt vil give en fordel i forhold til den løsning man nu har valgt. ) Som jeg har hørt kommer der krav om LCA med i den kommende udgave af bygningsreglementet, samt at ENS er i gang med at udvikle et nyt værktøj hertil – måske kunne det også være en ”point-of-departure” (især siden der ville være mange som er helt blank omkring emnet ;)
Jeg ved ikke om det hjælper dig videre i den indledende søgen – og sig til hvis jeg kan hjælpe med at få emnet mere konkret.
Du er også velkommen til at komme forbi hos os, så kan vi - måske sammen med Søren – finde et emne fra vores hverdag.
Mange hilsner, jan
jan schipull kauschen arkitekt maa vandkunsten
krudtløbsvej 14 dk-1439 københavn k www.vandkunsten.com +45 6040 2785
Fra: Christine Collin [mailto:chris_collin@hotmail.com]
Sendt: 27. oktober 2014 09:54 Til: Jan Kauschen
Emne: Speciale - LCA Hej Jan
Jeg skriver til dig på opfordring af Søren Nielsen da jeg tidligere i forindelse med mit bachelorprojekt har haft kontakt med Vandkunsten og Søren.
Jeg skal påbegynde mit speciale i august 2015 og søger derfor nogle emner som vil være relevante for industrien at undersøge - jeg er derfor meget interesseret i at høre om I har nogle problemstillinger i hverdagen I ikke selv har
tid/ressourcer til at undersøge nærmere, og i så fald hvilke?
Jeg er selv stadig meget interesseret i LCA'ens muligheder og begrænsninger og synes bestemt det kunne være spændende at se nærmere på lovgivningen fx. i forhold til de problemstilling der kan opstå i forbindelse med
konkurrenceforslag og bygherres ønsker/krav eller mangel på samme. Allerhelst vil jeg selvfølgelig give mig i kast med noget som kunne være relevant for industrien, hvorfor jeg har henvendt mig til Vandkunsten endnu en gang.
Jeg håber du kan give et indspark i forhold til hvad du ser som relevante forskningsemner indenfor de kommende år.
Mvh. Christine Collin
Studerende ved DTU, Msc. Architectural Engineering From: sn@vandkunst.dk
To: chris_collin@hotmail.com
Subject: SV: SV: SV: SV: Interview omhandlende Det moderne Tanghus, Speciale Date: Sun, 26 Oct 2014 18:27:36 +0000
Hej Christine
Tak for din mail, og undskyld sent svar. Vi har for nylig ansat Jan Schipull som har lavet LCA’en på vores tanghus. Jeg tror at han vil være den allerskarpeste til at give et bud på forskningsemner, og sætter ham på cc. Jeg foreslår at du kontakter ham!
*søren
Fra: Christine Collin [mailto:chris_collin@hotmail.com]
Sendt: 20. oktober 2014 13:25 Til: Søren Nielsen
Emne: RE: SV: SV: SV: Interview omhandlende Det moderne Tanghus, Speciale Hej Søren
Endnu en gang tak for hjælpen tilbage i 2013 med mit bachelorprojekt og den efterfølgende feedback!
problemstillinger I hverdagen I ikke selv har tid/ressourcer til at undersøge nærmere, er jeg meget interesseret I at høre om disse.
Jeg er selv stadig meget interesseret i LCA'ens muligheder og begrænsninger og synes bestemt det kunne være spændende at se nærmere på lovgivningen fx. i forhold til den problemstilling som du nævner I stod i, (konkurrenceforslag til et byggeri i Stockholm, 2013) . Allerhelst vil jeg selvfølgelig give mig i kast med noget som kunne være relevant for industrien, hvorfor jeg skriver til dig.
Jeg håber du kan give et indspark i forhold til hvad du ser som relevante forskningsemner indenfor de kommende år.
Mvh. Christine Collin
Studerende ved DTU, Msc. Architectural Engineering From: sn@vandkunst.dk
To: chris_collin@hotmail.com
Subject: SV: SV: SV: Interview omhandlende Det moderne Tanghus Date: Mon, 21 Apr 2014 11:06:08 +0000
Hej Christine
Fantastisk opgave! Meget relevant og interessant.
Den er naturligvis et øjebliksbillede, fordi udviklingen går så hurtigt på det felt. I forhold til diskussionen om lovgivning kan jeg tilføje, at validiteten af dataene er en meget vigtig faktor. Den europæiske produktdeklarationslovgivning er ikke fuldt implementeret endnu, men EPD-oplysningerne er nøglen til en mulig lovgivning. Så længe man ikke med nogenlunde sikkerhed kan vide f.eks. hvilken energisammensætning der ligger til grund for produkterne er der ikke grundlag for at stille specifikke krav i lovgivningen.
En anden og mere pragmatisk vej at gå i overgangen til en lovgivning har jeg et dagsaktuelt eksempel på . Vi laver nu et konkurrenceforslag til et byggeri i Stockholm, hvor kommunen kræver at der laves LCA, men kun på to parametre:
energi og GWP. Her forudsættes det eksplicit, energisammensætningen er udefineret, dvs. det er de øvrige parametre der afgør det. I Jan Schipulls
undersøgelse af tanghuset var netop energisammensætningen den altafgørende faktor som kunne 'relativere' alt andet til ubetydeligheder. Det synliggør, at de vigtigste beslutninger vedrørende bæredygtighed slet ike ligger hos designerne, men på de store energipolitiske linjer. Det kan derfor være produktivt at sætte parantes om energisammensætningen for at vi kan øve os i at tage de rigtige beslutninger indenfor det domæne, hvor vi råder som designere.
Fortsæt det fine arbejde. Jeg glæder mig til at læse mere!
*søren