CONSIDERING SUSTAINABLE DEVELOPMENT DECISION IMPACTS IMPACTS IN LIFE CYCLE ANALYSES AND TESTING METHODOLOGIES FOR TESTING METHODOLOGIES FOR CONCRETE TRANSPORTATION MATERIALS MATERIALS Liv Haselbach Civil and Environmental Engineering Civil and Environmental Engineering US-Japan Workshop on Life Cycle Assessment of US Japan Workshop on Life Cycle Assessment of Sustainable Infrastructure Materials : Sapporo, Japan, October 21-22, 2009
Concrete and LCA in the Future? Sustainable development adoption for the • transportation industry which may result in d h h l Novel material alternatives – Modified testing methods – Adapted life cycle analyses – Current focus on producing concrete- based • infrastructure with a lower carbon footprint infrastructure with a lower carbon footprint LCAs must include the cradle to gate analyses And the fate and transport of carbon during the operational life and disposal Absorption of carbon dioxide by concrete is • encouraged, changing material characteristics Need for alternative reinforcing materials? • Testing Method Modifications? •
Pervious Concrete A Novel Sustainable Material
Safety • Less hydroplaning L h d l i • Reduces slickness of roadways f • Reduces ponding/ ice in parking lots P PerviousPavement.org i P t
Source (EPA, 1992) Mitigates Heat Island Effect
Decreases Erosion • Pervious Concrete spreads water • No Channeling on g road Shoulders
Concrete Carbon Footprint • Absorbs CO 2 from atmosphere Absorbs CO from atmosphere • ‘Carbonation’ Process (One theory) CO 2 (g) + H 2 O(l) = H 2 CO 3 (aq) CO (g) + H O(l) H CO (aq) H 2 CO 3 (aq) = H + (aq) + HCO 3 - - (aq) = H + (aq) + CO 3 2- (aq) HCO 3 3 ( q) ( q) ( q) 3 Ca(OH) 2 (s) = Ca 2+ (aq) + 2OH - (aq) H + (aq) + OH - (aq) = H 2 O(l) ) + CO 2 ( 2- (aq) = CaCO 3 (s) Ca 2+ (aq) + CO 3 C 2+ ( ) C CO ( ) • Simplified Equilibrium Equation CO 2 (g) + Ca(OH) 2 (s) = H 2 O(l) + CaCO 3 (s) CO (g) + Ca(OH) (s) H O(l) + CaCO (s)
Concrete Carbon Footprint • May make concrete with more carbonate May make concrete with more carbonate • May use ‘carbonated’ RCA in concrete • Other ideas??????? • Therefore infrastructure materials in the f future may have altered compositions! h l d
pH Change with Carbon Absorption Effect on Reinforcing Steel? Figure 1: pH of CaCO 3 -Ca(OH) 2 Aqueous Suspension as a Function of Carbon to Calcium Mole Ratio Figure 1: pH of CaCO Figure 1: pH of CaCO 3 - Ca(OH) 2 Aqueous Suspension as a Ca(OH) Aqueous Suspension as a Function of Carbon to Calcium Mole Ratio
Other Changes g in the Chemistry of Concrete 4E-9 3E-9 ] Signal [Amps 2E-9 1E-9 1E-9 0 0 100 200 300 400 500 600 700 Temperature [ ° C] Figure 2: Water Desorption Curve for Typical Room Area Open (AO) and Oven Open (OO) Samples Haselbach, L. and Liu, L., Calcium Hydroxide Formation in Thin Cement Paste Samples Exposed to Air submitted to ACI Materials 2009
Oth Other Changes Ch in the Chemistry of Concrete 4E-9 3E-9 gnal [Amps] 2E-9 Si 1E-9 0 0 100 200 300 400 500 600 700 Temperature [ ° C] Figure 3: Water Desorption Curve for Typical Room Area C Covered (AC) and Oven Covered (OC) Samples d (AC) d O C d (OC) S l Haselbach, L. and Liu, L., Calcium Hydroxide Formation in Thin Cement Paste Samples Exposed to Air submitted to ACI Materials 2009
FRP as a Sustainable Alternative • In Novel Uses Such as Pervious Concrete • In More “carbon neutral” Concrete Mixes With accelerated carbonation With enhanced levels of SCMs
ISO and Environmental Management of Concrete Structures • What Environmental Impacts Should be Used? • Carbon Dioxide was only Recently Adopted b d l l d d as an air Pollutant in the US • What Environmental Issues Will Arise in the Wh E i l I Will A i i h Future?
Do We Also Need to Adapt Our Standardized Testing Methods? ASTM Number Title C 39/C 39M - 05 Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens C 1609/C 1609M - 07 C 609/C 609 07 S a da d Standard Test Method for Flexural Performance of Fiber- es e od o e u a e o a ce o be Reinforced Concrete (Using Beam with Third-Point Loading) C 31/C 31M – 08a Standard Practice for making and Curing Concrete Test Specimens in the Field C 192/C 192M - 07 Standard Practice for making and Curing Concrete Test Specimens in the Laboratory C 617 – 98 (2003) Standard Practice for Capping Cylindrical Concrete Specimens C 511 - 06 C 511 06 Standard Specification for Mixing Rooms Moist Cabinets Standard Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes C 873/C 873M - 04 Standard Test Method for Compressive Strength of C Concrete Cylinders Cast in Place in Cylindrical Molds C li d C i Pl i C li d i l M ld C 330 - 05 Standard Specification for Lightweight Aggregates for Structural Concrete
Testing Summary • ASTM C 39/ C 39M – 05 and ASTM C 1609/ C 1609M – 07 refer to either ASTM C 31/ C 31M – 08a or ASTM C 192/ C 192M – 07 for the standard 08 ASTM C 192/ C 192M 07 f h d d practice of final curing of the prepared samples. • ASTM C 617 – 98 (2003) is an alternative for ASTM C 617 98 (2003) i lt ti f cylinder curing when freshly molded specimens are capped with neat cement. are capped with neat cement. • These standard final curing practices maintain a high moisture level, usually in a water tank, in g , y , water saturated with calcium hydroxide, in a moist room or appropriately wrapped. ASTM C 511 – 06 gives specifications for many of the 511 06 i ifi ti f f th available high moisture curing facilities [32].
Summary Point One • Many future concrete mixes and applications will not be amendable to more traditional will not be amendable to more traditional reinforcing technologies such as reinforcing steel. Therefore alternative technologies such as the use of FRPs will need to be h h f FRP ill d b considered.
Summary Point 2 • An environmental life cycle assessment of y concrete needs to include its entire life due to the variability in mix designs and its dynamic chemical make up This is dynamic chemical make- up. This is particularly important when determining the carbon footprint of concrete as concrete can p be produced with varying levels of carbon dioxide and has the potential for carbon dioxide sequestering during its primary life di id t i d i it i lif and also during alternative secondary applications. applications.
Summary Point 3 Summary Point 3 • As sustainable development principles promote alternative mix designs and novel promote alternative mix designs and novel concrete applications, the standardized tests used to determine life cycle factors such as durability and strength may need to be appropriately modified to include the associated chemical and environmental associated chemical and environmental changes. Of specific note is the potential change in calcium hydroxide composition in g y p novel concrete applications and the resulting change in pH. This might alter the conditions under which testing specimens conditions under which testing specimens should be cured.
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