A new generation of sustainable structural concretes – Design approach and material properties

1. A new generation of sustainable structural concretes – Design approach and material properties Harald S. Müller M. Haist, J. Moffattand M. Vogel Prague, Czech Republic Juli 2nd, 2019

2. Outline A new generation of sustainable structural concretes • Motivation andchallenge • Introductionandapproachesrelatedtosustainability • Design andpropertiesofsustainableconcrete • Sustainabilityevaluationforstructuralconcrete • Conclusionsandoutlook

3. Construction sector worldwide – some facts • The constructionsectorconsumes 40 % oftheavailableenergy • The useofconcretecorrelatesstronglywiththeeconomicalgrowthandthedevelopmentofthecivilinfrastructure • Concreteisindispensibleas a building material; annualproduction: 7 billion m³/year; strong increaseexpected • Concreteproductionisassociatedwith 6 - 8 % ofthe global CO2 emissionstoday Hong Kong Los Angeles

4. Sustainability – Definitions and approaches Original meaning ... Sustainablebuildings (housingandofficeuse) Forestrymanagement Relatedtosociety … Sustainability of structures is generally measured using indexing systems, whichaccount for various technical and non-technical properties Brundtland Commission [Wikicommons, Blocherblocher.com, Wikipedia]

5. Sustainability – Definitions Sustainableinfrastructure Sustainablebuildings (housingandofficeuse) ? Forestry Society imagesources: Wikicommons, Blocherblocher.com, Wikipedia http://ais.badische-zeitung.de/piece/04/95/1b/e5/76880869.jpg Quelle: http://partners.blocherblocher.com/de/projekt/buerogebaeude-stuttgart.html

6. Sustainability – Definitions ? Forestry Sustainablebuildings (housingandofficeuse) Sustainableinfrastructure Sustainablematerials Society ? imagesources: Wikicommons, Blocherblocher.com, Wikipedia http://ais.badische-zeitung.de/piece/04/95/1b/e5/76880869.jpg Quelle: http://partners.blocherblocher.com/de/projekt/buerogebaeude-stuttgart.html

7. Sustainabilityrelated to structuralconcrete – Effectingparameters • service life • environmental impact • performance

8. Sustainability of concrete servicelife performance • increase service life by • adequate service life design • monitoring and structural inspection • adequate rehabilitation work • keep structure attractive to user • increase performance by • concretes with increased strength and durability • materials with additional functionality • improve resilience maximize environmental impact • use of raw materials with reduced eco-impact, e.g. composite cements, recycled concrete • development of concretes with reduced binder and/or cement clinker content • development of environmentally friendly production and building techniques minimize

9. Sustainability of concrete servicelife performance • increase service life by • adequate service life design • monitoring and structural inspection • adequate rehabilitation work • keep structure attractive to user • increase performance by • concretes with increased strength and durability • materials with additional functionality • improve resilience maximize environmental impact • use of raw materials with reduced eco-impact, e.g. composite cements, recycled concrete • development of concretes with reduced binder and/or cement clinker content • development of environmentally friendly production and building techniques minimize

10. Efficiency ofcementuse in concrete binderintensity: Source: Daminelli et al. (2010)

11. Improvement of concretesustainability binderintensity: reduction of bindercontent increase of compressivestrength Source: Daminelli et al. (2010)

12. Improvement of concretesustainability binderintensity: > 90 % ofconcreteused reduction of bindercontent increase of compressivestrength Source: Daminelli et al. (2010)

13. Paths toward sustainable concrete Aim: Minimal use of materials with significant influence on environmental impact 1 m³ 1. New binder materials Standard concrete Standard concrete 2. Substitution by SCMs 3. Increase agg. content Standard concrete admixtures admixtures admixtures water water water cement cement cement SCMs SCMs SCMs e.g. fly ash (FA) or blast furnace slag (BFS) and others Celitement, calc. clays, … without SCMs! aggregates aggregates aggregates Binder / cementcontent: 100 kg/m³ insteadof 300...350 kg/m³ 1 m³ 1 m³ 1 m³

14. Cement-reducedconcretecomposition Packingoptimization

15. Cement-reducedconcrete – developmentsrequired Virtual concrete mix design Effectofplasticizers Today: Plasticizersinteractonlywithcement Cement LSP LSP Cement Cement Quartz FA LSP Quartz FA Tomorrow: Interaction with all fines Cement Quartz LSP Cement Cement LSP FA Quartz • Optimierte Packung: • Basic models: • de Larrard, Fennis Source grafic: BASF

16. Compressivestrengthofconcrete eco-concretes

17. Durabilityofconcrete Carbonation test Rapid chloride migration test determined at 2 vol.-% CO2-concentration determined at 2 vol.-% CO2-concrentation

18. Service lifeofconcrete concretecoverc = const. concretecover c andcarbonationdepth xc(t) CO2 concrete reinforcingbar time t calculationof deterministicservicelife

19. Service lifeofconcrete failureprobability concretecoverc = const. concretecover c andcarbonationdepth xc(t) reliability index β(t) time t probabilisticservicelifetsl calculationof

20. Service lifeofconcrete limitstate β = 1.3 36 55 85 106

21. Sustainability of concrete lifecycle→ servicelifetsl performance→ compressivestrength env. impact→ global warming potential

22. Sustainability potential of concrete NHP Aktualisiert

23. Sustainability potential of concrete NHP Aktualisiert

24. Sustainability potential on a structurallevel Mechanicaltestingof ECO-beams testacc. DAfStb, FRC

25. Sustainability potential on a structurallevel F-δ-behaviorof ECO-beams Mechanicaltestingof ECO-beams testacc. DAfStb, FRC

26. Sustainability potential on a structurallevel F-δ-behaviorof ECO-beams Mechanicaltestingof ECO-beams testacc. DAfStb, FRC

27. Sustainability potential on a structurallevel F-δ-behaviorof ECO-beams Mechanicaltestingof ECO-beams testacc. DAfStb, FRC

28. Sustainability potential on a structurallevel F-δ-behaviorof ECO-beams Mechanicaltestingof ECO-beams testacc. DAfStb, FRC

29. Sustainability potential on a structurallevel F-δ-behaviorof ECO-beams Mechanicaltestingof ECO-beams testacc. DAfStb, FRC

30. Sustainabilityaspectsofgradation homogeneousbeams gradedbeams Reductionof environmental impact at equalloadbearingbehaviorpossible!

31. Conclusions and outlook • The sustainability of concrete increases with • reduced environmental impact • increasing service life • increasing performance or a combination of these approaches New binder materials Ecological concrete UHPC concrete Reduction of environmental impact during cement and binder production Development of cement-reduced, durable and ecologically optimized concretes Development of high performance concretes with maximal performance A combination of concretes with varying performance properties Best possible exploitation of the material performance on a structural level ! Variousproblems still tobesolved: durabilitybehavior, deteriorationmodelling, freshconcreteproperties, concreting, qualityassuranceregime, …

32. Thankyou foryourattention Scan QR ordownloadfullpaper atcesb.cz/19/0002 The authorswould like tothankthe Helmholtz Associationforsupportingthisresearch