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transcript
Improving the Performance of Recycled Aggregate
Pervious Concrete via Cement Binder Additives ACI Convention Spring 2015
Patrick Barnhouse, EIT | MS Candidate
Sustainable Infrastructure Materials Laboratory (SIMLab) University of Colorado Boulder
April 15, 2015
Agenda
• Beyond Horizontal Infrastructure
• Macroporous Pervious Concrete
• Materials and Methods
• Mix Designs
• Results
• Property Relationships
• Conclusions
• Future Research
2
Beyond Horizontal Infrastructure
• Examples
o Historic
-Post World War II Europe 7
o Future Opportunity
-Sound barriers and reinforced panels 8
-Tennis courts 7
-Solar heating systems 7
-Marine “biohabitats” 9
• Properties of Interest
o Acoustic
o Thermal
o Porous
(Tarnai, et al. 2003)
4
Beyond Horizontal Infrastructure
• Material Design for Alternative Applications
• Favor properties other than mechanical
-e.g. acoustic absorption and high porosity over high strength
• No substantive research has been conducted on such
a material
• Main research focus has been on material for horizontal
infrastructure (5-30% porosity)
5
Macroporous Pervious Concrete
• Macroporous Pervious Concrete (MPC)
• Pervious concrete with a porosity > 30%
• Expected Properties
• Low Strength
• High Permeability
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Macroporous Pervious Concrete
• Alternative Applications
o Historic Example
-Post World War II Europe 7
o Future Opportunity
-Sound barriers and reinforced panels 8
-Tennis courts 7
-Solar heating systems 7
-Marine “biohabitats” 9
• Properties of Interest
o Acoustic
o Thermal
o Porous
(Tarnai, et al. 2003)
8
Macroporous Pervious Concrete
• Macroporous Applications
o Historic Example
-Post World War II Europe 7
o Future Opportunity
-Sound barriers and reinforced panels 8
-Tennis courts 7
-Solar heating systems 7
-Marine “biohabitats” 9
• Properties of Interest
o Acoustic
o Thermal
o Porous
(Tarnai, et al. 2003)
9
Materials and Methods
• Research Goal
• Investigate and Characterize MPC
• Analyze mechanical and physical properties
• Observe the potential for sustainability
• Research Design
• Replace virgin aggregate with recycled concrete aggregate (RCA)
Work to sustainability
• Incorporate sand and the photocatalyst titanium dioxide (TiO2) as
cement binder additives
Maintain or improve performance
• Compare MPC properties to conventional pervious concrete
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Materials and Methods
• Mortar Compressive Testing
o Effective proxy of studying the paste of MPC
o Study the impact of TiO2 on binder strength
-Previous studies have shown promise 10,11
12
Materials and Methods
• MPC Casting
o Light compaction
• MPC Mechanical Testing
o Compression testing
o Observe the impact of RCA 12-14, sand 15 and TiO2
• MPC Physical Measurements
o Porosity
o Permeability
13
Materials and Methods
• Simulated Field Testing
o Pervious concrete is sensitive to moisture while curing 16
o Ideal conditions may not give realistic results
• Mortar Field Conditions
o Exposed to ambient conditions
o Control specimen cured for comparison
• MPC Field Conditions
o Wrapped in plastic for 7 days 17
o Exposed to ambient conditions
14
Mix Designs
• Mortar Cubes
o Three (3) sets of six (6) cubes for each formulation
o “2.5” or “5” = % addition of binder
o “C” or “T” = Cement or TiO2 binder material
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Mix Designs
• MPC Cylinders
o Seven (7) mixes to study aggregate and paste
o “2.5” or “5” = % addition of TiO2
o “RCA” or “RCAs” = Recycled Aggregate or Recycled Aggregate
with Sand
o “HRWR” = High Range Water Reducer
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Results
• Mortar Cubes
TiO2 gave early strength benefits
TiO2 performed better than cement for 3- and 7-day tests
5% addition of TiO2 gave no significant benefit at 28-days
2.5% TiO2 gave more strength improvement than ideal-curing
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Results
• Mortar Cubes
o % increase is the relative gain from one w/b ratio to the other
Both additions of TiO2 gave noticeable increases
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Results
• Mortar Cubes
o % increase is the relative gain from one w/b ratio to the other
2.5% TiO2 comparable to ideal-curing
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Results
• MPC Cylinder
o Strengths are low—non-pavement applications
No difference between aggregate type
2.5% TiO2 was beneficial while 5% TiO2 was detrimental
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Results
• MPC Cylinder
RCA has the largest porosity and permeability
Permeability follows porosity
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Property Relationships
• MPC Cylinder
o Carman-Kozeny model used to predict permeability 20,21
o Coefficient varies for data sets
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𝐾 = 𝛼𝑝3
1 − 𝑝 2
K = permeability (cm/s)
p = porosity (%)
α = empirical coefficient
(Eqn 1)
Property Relationships
• MPC Cylinder
o Carman-Kozeny model used to predict permeability 20,21
Coefficient varies for data sets
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Property Relationships
• MPC Cylinder
o Proposed piecewise solution
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𝐾 =
= 30𝑝3
1 − 𝑝 2 𝑖𝑓 𝑝 ≤ 30%
= 45𝑝3
1 − 𝑝 2 𝑖𝑓 𝑝 ≥ 30%
(Eqn 2)
K = permeability (cm/s)
p = porosity (%)
Property Relationships
• MPC Cylinder
o Proposed piecewise solution
Modified Carman-Kozeny sufficiently fits all data
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Conclusions
TiO2-Cement Materials
1. TiO2 enhances early strength and 28-day strength
2. 2.5% TiO2 by weight of cement is suggested addition
• Enhance hydration without negative side effects
3. Field simulation is key for TiO2-cement materials
• Results differ from existing data
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Conclusions
Macroporous Pervious Concrete (MPC)
1. RCA can be used without a loss in performance
2. Sand was more beneficial than TiO2
• Work best together
3. Strength independent of porosity & unit weight
• Atypical for pervious concrete
4. Modified Carman-Kozeny model required
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Future Research
• MPC Properties
• Life Cycle Analysis
• Further characterization of
MPC
-Tensile strength
-Freeze-thaw durability
• Binder strength improvements
for MPC
-SCMs
-Internal Curing
• Slab vs cylinder results
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• TiO2-Cement Materials
• Mechanical properties of
TiO2 additions on
conventional pervious
concrete
• Impact of TiO2 on rheology
of fresh-state pervious
concrete
• Lower doses of TiO2
References
[1] Welker AL, Barbis JD, Jeffers PA. A Side-by-Side Comparison of Pervious Concrete and Porous Asphalt. Journal of the American Water Resources Association 2012;48:809–19. [2] Haselbach L. Pervious Concrete and Mitigation of the Urban Heat Island Effect. Transportation Research Board 88th Annual Meeting, 2009. [3] Haselbach L, Boyer M, Kevern JT, Schaefer VR. Cyclic Heat Island Impacts on Traditional Versus Pervious Concrete Pavement Systems. Transportation Research Record 2011;2240:107–15. [4] Starke P, Gobel P, Coldeway WG. Urban Evaporation Rates for Water Permeable Pavements. Water Science and Technology 2010;62:1161–9. [5] Nemirovsky EM, Welker AL, Lee R. Quantifying Evaporation from Pervious Concrete Systems: Methodology and Hydrologic Perspective. Journal of Irrigation and Drainage Engineering-ASCE 2013;139:271–7. [6] Goel PK. Water Pollution-Causes, Effects and Control. New Delhi: New Age International; 2006. [7] Ghafoori N, Dutta S. Building and Nonpavement Applications of No-Fines Concrete. Journal of Materials in Civil Engineering 1995;7:286–9. [8] Carsana M, Tittarelli F, Bertolini L. Use of no-fines concrete as a building material: Strength, durability properties and corrosion protection of embedded steel. Cement and Concrete Research 2013;48:64–73. doi:10.1016/j.cemconres.2013.02.006. [9] Tarnai M, Mizuguchi H, Hatanaka S, Katahira H, Nakazawa T, Yanagibashi K, et al. Design, Construction and Recent Applications of Porous Concrete in Japan. Our World in Concrete and Structures, Singapore: 2003. [10] Chen J, Kou SC, Poon CS. Hydration and properties of nano-TiO2 blended cement composites. Cement and Concrete Composites 2012;34:642–9. doi:10.1016/j.cemconcomp.2012.02.009. [11] Jayapalan AR, Jue ML, Kurtis KE. Nanoparticles and apparent activation energy of Portland cement. Journal of the American Ceramic Society 2014;97:1534–42. doi:10.1111/jace.12878. [12] Berry BM, Suozzo MJ, Anderson I a., Dewoolkar MM. Properties of Pervious Concrete Incorporating Recycled Concrete Aggregate. Transportation Research Board Annual Meeting, 2012. [13] Gaedicke C, Marines A, Miankodila F. A method for comparing cores and cast cylinders in virgin and recycled aggregate pervious concrete. Construction and Building Materials 2014;52:49–503. [14] Rizvi R, Tighe S, Henderson V, Norris J. Evaluating the Use of Recycled Concrete Aggregate in Pervious Concrete Pavement. Transportation Research Record: Journal of the Transportation Research Board 2010;2164:132–40. doi:10.3141/2164-17.
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[15] Kevern JT, Schaefer VR, Wang K, Suleiman MT. Pervious Concrete Mixture Proportions for Improved Freeze-Thaw Durability. Journal of ASTM International 2008;5:101320. doi:10.1520/JAI101320. [16] American Concrete Institute (ACI). 2013. “ACI 522.R-10—Report on Pervious Concrete.” Farmington Hills, MI. [17] American Concrete Institute (ACI). 2010. “ACI 522.1-1—Specification for Pervious Concrete Pavement.” Farmington Hills, MI. [18] Chen J, Poon CS. Photocatalytic construction and building materials: From fundamentals to applications. Building and Environment 2009;44:1899–906. doi:10.1016/j.buildenv.2009.01.002. [19] Diamanti MV, Ormellese M, Pedeferri M. Characterization of photocatalytic and superhydrophilic properties of mortars containing titanium dioxide. Cement and Concrete Research 2008;38:1349–53. doi:10.1016/j.cemconres.2008.07.003. [20] Kevern JT, Schaefer VR. Mixture Proportioning Considerations for Improved Freeze-Thaw Durability of Pervious Concrete. ISCORD 2013:471–81. [21] Montes F, Haselbach L. Measuring Hydraulic Conductivity in Pervious Concrete. Environmental Engineering Science 2006;23:960–9. doi:10.1089/ees.2006.23.960.
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Proposed Mechanism
• Field Simulated Curing
1. UV Radiation
-TiO2 is hydrophilic after UV exposure 18,19
2. Autogeneous shrinkage
-TiO2 particle size makes path more tortuous
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Sustainability
• MPC Sustainability
Incorporation of TiO2
-Improved strength
-Pollutant removal
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