Chapter 5. Silica-Fume Concrete Projects Bridge Decks Parking Structure High-Rise Columns HPC Bridge Shotcrete Rehabilitation HPC Constructability
Bridge Decks -- New Construction and Overlays (Fly Ash and Silica Fume Combination) Chapter Outline
Project: Bridge Deck Construction New York State DOT High-Performance Concrete Requirements: Resist chloride ion penetration Minimize cracking
Concrete Mixture: Portland cement 500 lb/yd 3 Fly ash135 lb/yd 3 Silica fume 40 lb/yd 3 w/cm0.40 Slump3-4 inches Air6.5 % Wet cure7 days
Concrete Performance: “Results indicated that Class HP decks performed better than previously specified concrete in resisting both longitudinal and transverse cracking.” Rapid chloride permeability: < 1,600 coulombs Compressive strength, 28 days: > 5,400 psi
Project: Requirements: Resist chloride ion penetration Minimize cracking SI Bridge Deck Construction New York State DOT High-Performance Concrete
Concrete Mixture: Portland cement300 kg/m 3 Fly ash 80 kg/m 3 Silica fume 25 kg/m 3 w/cm0.40 Slump mm Air6.5 % Wet cure7 days SI
Concrete Performance: SI Rapid chloride permeability: < 1,600 coulombs Compressive strength, 28 days: > 37 MPa “Results indicated that Class HP decks performed better than previously specified concrete in resisting both longitudinal and transverse cracking.”
Bridge Deck Overlay (High Silica Fume Content) Chapter Outline
Project: Bridge Deck Overlay, Ohio DOT Beverly, Ohio Requirements: Resist chloride ion penetration 4,500 psi at 28 days RCP < 1,000 coulombs
Concrete Mixture: Portland cement, Type I700 lb/yd 3 Silica fume 70 lb/yd 3 w/cm0.36 Slump4-8 in. Air6-10% HRWRA20 fl oz/cwt WRA, Type D 3 fl oz/cwt
Concrete Performance: Rapid chloride permeability600 coulombs Compressive strength, 28 days 7,000 psi
Project: Bridge Deck Overlay, Ohio DOT Beverly, Ohio Requirements: Resist chloride ion penetration 31 MPa at 28 days RCP < 1,000 coulombs SI
Concrete Mixture: Portland cement, Type I415 kg/m 3 Silica fume 41.5 kg/m 3 w/cm0.36 Slump mm Air6-10% HRWRA1.3L/100 kg WRA, Type D 165 ml/100 kg SI
Concrete Performance: Rapid chloride permeability 600 coulombs Compressive strength, 28 days 48 MPa SI
Parking Structure Chapter Outline
Project: Parking Structure General Mitchell Airport Milwaukee, Wisconsin Requirements: Resist chloride ion penetration 2,000 psi at 36 hours 5,700 psi at 56 days
Concrete Mixture: Portland cement, Type I565 lb/yd 3 Fly ash, Class C100 lb/yd 3 Silica fume 39 lb/yd 3 w/cm0.35 WRA12 fl oz/yd 3 Slump, maximum9 in. Additional WRA and HRWRA in SF slurry
Concrete Performance: Compressive strength, 36 hours:> 2,000 psi Cores taken at months averaged < 1,000 coulombs Slump used: in.
Project: Parking Structure General Mitchell Airport Milwaukee, Wisconsin Requirements: Resist chloride ion penetration 14 MPa at 36 hours 40 MPa at 56 days SI
Concrete Mixture: Portland cement, Type I335 kg/m 3 Fly ash, Class C60 kg/m 3 Silica fume 17 kg/m 3 w/cm0.35 WRA440 mL/m 3 Slump, maximum230 mm Additional WRA and HRWRA in SF slurry SI
Concrete Performance: Compressive strength, 36 hours> 14 MPa Cores taken at months averaged < 1,000 coulombs Slump used: mm SI
High-Rise Columns Chapter Outline
Project: Key Bank Tower Cleveland, Ohio Requirements: High ultimate strength, > 12,000 psi High modulus, > 6,800,000 psi Pumpable, 57 stories
Concrete Mixture: Portland cement, Type I 685 lb/yd 3 GGBFS 285 lb/yd 3 Silica fume 80 lb/yd 3 w/cm 0.24 Slump, minimum 10 in. HRWRA fl oz/cwt WRA, Type A 4 fl oz/cwt
Concrete Performance: Modulus> 7,000,000 psi Compressive strength, 28 days > 14,000 psi 56 days> 15,000 psi
Project: Key Bank Tower Cleveland, Ohio Requirements: High ultimate strength, > 83 MPa High modulus, > 47 GPa Pumpable, 57 stories SI
Concrete Mixture: Portland cement, Type I 406 kg/m 3 GGBFS 169 kg/m 3 Silica fume 47 kg/m 3 w/cm 0.24 Slump, minimum 250 mm HRWRA L/100 kg WRA, Type A 260 mL/100 kg SI
Concrete Performance: Modulus> 48 GPa Compressive strength, 28 days > 97 MPa 56 days > 103 MPa SI
HPC Bridge Chapter Outline
Project: I-25 and Yale Bridge, Colorado DOT Denver, Colorado Requirements: Reduced number of spans with shallow superstructure depth Compressive strength: 10,000 psi
Concrete Mixture: Portland cement, Type I730 lb/yd 3 Silica fume 35 lb/yd 3 w/cm0.29 HRWRA fl oz/yd 3 WRA fl oz/yd 3
Project: I-25 and Yale Bridge, Colorado DOT Denver, Colorado Requirements: Reduced number of spans with shallow substructure depth Compressive strength: 69 MPa SI
Concrete Mixture: Portland cement, Type I433 kg/m 3 Silica fume 21 kg/m 3 w/cm0.29 HRWRA L/m 3 WRA L/m 3 SI
Shotcrete Rehabilitation Chapter Outline
Project: Seismic Retrofit Littlerock Dam, California Requirements: Provide adequate seismic stability for maximum credible earthquake Compressive strength of 6,000 psi at 28 days in a 4-in. thick overlay
Concrete Mixture: Portland cement, Type I682 lb/yd 3 Silica fume 70 lb/yd 3 Steel fibers100 lb/yd 3 w/cm0.45 Slump2-4 in.
Concrete Performance: Compressive strength, cores, > 21 days, average 7,300 psi Pulloff testing of cores satisfied project requirements of 150 psi Average shotcrete thickness: 4.7 in.
Project: Seismic Retrofit Littlerock Dam, California Requirements: Provide adequate seismic stability for maximum credible earthquake Compressive strength of 41 MPa at 28 days in a 100-mm thick overlay SI
Concrete Mixture: Portland cement, Type I405 kg/m 3 Silica fume 41 kg/m 3 Steel fibers 60 kg/m 3 w/cm0.45 Slump mm SI
Concrete Performance: Compressive strength, cores, > 28 days, average > 50 MPa Pulloff testing of cores satisfied project requirements of 1.0 MPa Average shotcrete thickness: 119 mm SI
HPC Constructability Chapter Outline
Project: Canister Storage Building Hanford Nuclear Site, WA Requirements: Ease of placement Temperature control of mass concrete High early strength for stripping High durability
Concrete Mixture: Portland cement, Type I391 lb/yd 3 Fly ash, Class F 150 lb/yd 3 Silica fume 60 lb/yd 3 w/cm0.37 Slump8 in. HRWRA 150 fl oz/yd 3 Mid-range WRA 60 fl oz/yd 3
Concrete Performance: Concrete temperature, as delivered< 70 deg F in place < 100 deg F Compressive strength, 28 days> 6,300 psi 90 days > 7,500 psi
Concrete Mixture: Portland cement, Type I232 kg/m 3 Fly ash, Class F 89 kg/m 3 Silica fume 36 kg/m 3 w/cm0.37 Slump200 mm HRWRA 5.8 L/m 3 Mid-range WRA 2.3 L/m 3 SI
Concrete Performance: Concrete temperature, as delivered< 21 deg C in place < 38 deg C Compressive strength, 28 days> 43 MPa 90 days > 52 MPa SI
End of Chapter 5 Main Outline