4.461: Building Technology 1 FALL TERM 2004 …

1 : Building Technology 1 construction AND MATERIALSFALL TERM 2004 SCHOOL OF ARCHITECTURE AND PLANNING: MITP rofessor John E. FernandezConcrete and CompositesStadelhofenStationZurichSantia go CalatravaVallsImage courtesy of Per Waahlen, photographer, and Structuraeconcrete and composites1. Introductionpracticeresearch2. Concrete IssuesductilityCO2generationdurability3. Improved Structural Materialssubstitutiondematerializationte chnology transfer4. material Selection and Evaluation (CES)multi-objective optimizationmaterial indices/ CES software5.

2 New and Emerging Materialsnew concretescomposites6. Architectural Form and Research Priorities research development: NFRC designconcrete and composites1. Introductionpracticeresearch2. Concrete IssuesductilityCO2generationdurability3. Improved Structural Materialssubstitutiondematerializationte chnology transfer4. material Selection and Evaluationmulti-objective optimizationmaterial indices/ CES software5. New and Emerging Materialsnew concretescomposites6. Architectural Form research development.

3 NFRC designconcrete and compositesductilityelastic zoneStrain, dStress, sStrain, dStrain, d, DL/LStress, sStress, s, P/A E = Ds/DdDdDsbrittleductileplastic flowextensive cold drawing plasticpartial plasticity reinforced concretefull plasticity metalsbrittle ceramicsStress - Strain Curves Not To Scaleviscous flow elastomerImage by MIT and compositesductilityFailure strain, f f-measure of the deformation of the material at final fracture stressCeramicsFracture and failure is unpredictable Materialefconcrete, unreinforced(compression) , reinforcedsoda glasslow-alloy steelmild steelcarbon steelstainless steel,austeniticstainless steel,ferriticcast ironsironaluminumcopperbrasses and bronzesnatural rubberTensile Ductility, ef (except for certain materials such as concrete, unreinforced)Figure XFracture stress (ceramic)

4 Probability functionImages by MIT and compositesductilityToughness, Gf, and Fracture toughness, Kcmeasures of energy absorption potential through resistance to crack ( toughness), Kc(fracture toughness) -both material properties. Gf= energy per unit of crack area Various ways of measuring depending on the , search for materials that have high resistance to cracks that are formed through loading or other lifecycle toughness is also referred to as the area under the stress-strain curve. Price per density1101001000100001000001e6 Fracture Toughness ( ^1/2) FibreAlumina FibreCeramic foam (carbon)Normal Density ConcreteAerated ConcreteIce (H2O)Lightweight ConcreteGraniteLimestoneAluminium Nitrides (Glass ceramic)Silicon Nitride (Glass ceramic)

5 Machineable Glass CeramicLow Density Refractory Brickconcrete and compositesCO2generationEcological IssuesConcrete production contributes 8% of world s total in Building materials for the developing world is a moral Poverty allevation Safety Health (IAQ, toxicity) Resource ManagementCultural Issues Form (resonance with place) Process (acknowledges local skill set) material (regional resources)Production Energy (kcal/lb)110100100010000100000 Young's Modulus (10^6 psi) ( )Marble( )Granite( )Concrete (Insulating Lightweight)Concrete (High Performance)Common Hard BrickLow Density Refractory BrickPlaster of ParisCement (Super Sulphate)Ultra Low Density Wood (Transverse) ( )Insulation Board, perpendicular to boardNatural Rubber (NR), unfilledAluminaTungsten - High Alloy (<89%W)Medium Density Aluminium Foam ( )Carbon SteelEpoxy SMC (Carbon Fibre)

6 DiamondCarbon Matrix Compositeconcrete and compositesdurabilityConcreteNeed for durable reinforcing and water impermeable concrete matrixEspecially for freeze/thaw climatesconcrete and composites1. Introductionpracticeresearch2. Concrete IssuesductilityCO2 generationdurability3. Improved Structural Materialssubstitutiondematerializationte chnology transfer4. material Selection and Evaluationmulti-objective optimizationmaterial indices/ CES software5. New and Emerging Materialsnew concretescomposites6.

7 Architectural Form research developmentdesignconcrete and compositesdematerialization, substitution, Technology transfer020202025 YearQuantity (tons)2000197519501925190018751850182518 0017751750109108107106105104103102101 CAS(r)S(r)RRBABPPCGGS(n)S(n)W(r)W(n)W(n) ProjectionW(r)Image by MIT and compositesdematerialization, substitution, Technology transferConcreteDematerialization: a decrease in the material input per unit serviceIs occurring in certain industrial sectors but ecological rucksack needs to be accounted forSubstitution: substituting concrete best in situations in which safety is at high risk of compromiseTechnology transfer.

8 Best employed in situations in which to lengthen lives of existing Building stock (such as infrastructure refurbishment using carbon/epoxy reinforcing)40200608010020202010 YearPercentage of Total (weight)20001990198019701960195019401930 192019101900 Measurement of Percentage of Renewable Versus NonrenewableMaterials Consumption in the USProjectionImage by MIT and composites1. Introductionpracticeresearch2. Concrete IssuesductilityCO2 generationdurability3. Improved Structural Materialssubstitutiondematerializationte chnology transfer4.

9 material Selection and Evaluation (CES)multi-objective optimizationmaterial indices/ CES software5. New and Emerging Materialsnew concretescomposites6. Architectural Form research developmentdesignconcrete and compositesmulti-objective optimizationconcrete and compositesmulti-objective optimizationThermal Expansion ( strain/ F) 's Modulus (10^6 psi) Density ConcreteCarbon Steelceramics Glass ceramicsMachineable, good fracture toughness Very HPC (Ductal)Ductile concrete Ceramic foamsLightweight, structural material New laminated glasses Laminated glass (Dupont SGP interlayer)

10 Concrete and compositesnew concreteDuctile concreteSteel whisker reinforcementIncreased toughessIncreased water impermeability (few micropores)100203040506090012006003000 Displacement, micronsBending strength, MPaductile concretenormal concreteImage by MIT OCW.