1. CE 4002: Project
BE (Civil) Degree
Supervisor: Dr. Michael Creed
Daniel McAuliffe
Denis O’Sullivan
University College Cork
Coláiste na hOllscoile Corcaigh
Department of Civil and Environmental Engineering.

2. Poor Soil Additional
Standard Fill Subsidence
Conditions Loadings
High effective
Fill with and Deformation and
Construction stresses induced in
compact heavy Settlement of peat
planned peat (Overburden
granular fill layer
Pressure)
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3. Foamed
Concrete Fill
•⇒ No additional
Lightweight Loadings
No
Subsidence
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4. 1. Introduction
to the Material
6. Conclusion 2. Manufacture
Foamed
Concrete
5. Applications
and Case 3. Properties
Studies
4.
Environmental
Considerations
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5.  Lightweight (Range of Densities)
 Varying Strengths
 Rheology (Flowability)
 Self Compacting Cellular Concrete (California Lightweight
Concrete Inc., 2009. )
 Self levelling
 Consistency
Air Voids-Foamed Concrete (Provoton.com, 2008)
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6.  What it is made of ?
 How it is made ?
 Quality Control
Foam Concrete Mobile Batching Plant (construction int.com,2011)
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7.  Foam
 Foaming Agents
 Synthetic based
 Protein based
 Foam Types
 Wet
 Dry
Large Batch Foam Generator (foamedconcrete.co.uk,2010)
Wet Foam (Concrete Society, 2009) Dry Foam (Concrete Society, 2009)
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8.  Constituents
 Base Mix
Binding Agents Aggregates
Portland Cement Sand
Pulverised Fly Ash (PFA) Limestone
Ground Granulated Blastfurnace Slag (GGBS)
Admixtures Water
Set Controllers
Plasticizing agents
Fibres
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9.  Production
 Pre – foam method
 Inline method ( Wet and Dry )
Quality Control
Inline Dry System (Aldridge.D, 2005)

 Mixing
 Pouring Depth
 Pumping
Cellular Concrete (California Lightweight
Concrete Inc., 2009. )
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10.  Dependent on characteristics of the mix
 Materials and their quantities
 Binder
 Aggregate
 Foaming Agent
 Density: Most significant
 Quantity of foaming agent
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11.  Compressive Strength  Thermal Conductivity
 Flexural & Tensile  Resistance to Sulphate
Strength Attack
 Bearing Capacity  Resistance to
Carbonation
 Porosity
 Resistance to Freeze-
 Absorption Thaw Cycle
 Permeability  Resistance to
Penetration
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12.  Commonly Used
Mechanical Property
 Quantify Strength
 Dependent on
Density
 Air Void Content
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13.  Optimisation of Mix
 Roadway Base
 Low Density
 High Strength
∴ High Cost
Source: Amzi et al., 2005, p.42
 Satisfy Only 2
Parameters
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14.  Compressive Strength
 Flexural and Tensile Strength
 Bearing Capacity
 Thermal Conductivity
 Penetration Resistance
 Resistance to Sulphate Attack & Carbonation
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15.  Porosity
 Absorption
 Permeability
 Drying Shrinkage
 Freeze Thaw Resistance
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16.  Reduction in Energy Consumption/C02
Production
 Recycling of Waste Materials
Recycling Logo
Safety Considerations
(gvisionaries.files.wordpress.com,2011)

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17.  Use as a base or filling material under roadways
and structures.
 Filling of underground cavities and utilities.
 Reinstatement of trenches.
 Insulation of utilities or other elements.
 Base for sports fields.
 Improving stormwater runoff management.
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18. 1. Base in Road Widening Project, The
Netherlands.
2. Masonry Arch Bridge Infill
Investigation, Transport Research
Laboratory, UK.
3. Stabilisation of Combe Down Stone
Mines, Bath.
4. Trench Reinstatement in St. Helier, Jersey.
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19.  Need for extra capacity – Widening.
 Adjacent Dyke – Fill.
 Unstable Peat Soil.
 High Water Table.
 Deformation of Road Surface not Permitted.
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20.  Excavate soil & Infill
with Low Density
Foamed Concrete.
 Weight of Foamed
Concrete + Weight of
Roadway ≤ Weight of Effective Stress σ’
Increase Relative to
Soil Excavated Cross Section
(kN/m2)
Effective Stress of
Original Soil (kN/m2)
 Minimal Increase in 1 14.75 3.25
Vertical Effective 2 8.5 -3
Stress.
3 5.75 -5.25
Original Soil 11.5 -
Standard Fill, 40.75 29.25
 Settlement Prevented. Cross Section 1
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21.  Carried Out by Transport Research
Laboratory, Berkshire, UK .
 Specially Constructed Structure.
 Replacement of Granular Fill with Foamed Concrete
(1MPa, 1000 kg/m3)
 Series of Loading Tests
 50 kN Patch Loading at Midpoint.
 Increasing Linear Load across the Bridge: Serviceability Failure
 Increasing Linear Load across the Bridge: Collapse of Arch
 Vertical Displacement at Centre of Arch Monitored.
 Comparison with Standard Bridge.
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22.  Load Capacity
 F.C. Bridge ≈ 2.7 Standard Bridge.
 Stiffness (Based on Vertical Displacements).
 F.C. Bridge ≈ 2.8 Standard Bridge.
 Lighter Stronger Bridge Structure.
 Less Expensive Fill (30% Cheaper).
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23.  Shallow Limestone Mines.
 Variation in Height:
 0.5 – 10 metres.
 Variation in Roof Thickness:
 2 – 6 metres.
 Extraction Ratio > 80%.
 Support Pillars: Unstable.
 1300 Residents, A3602.
 Overlies Grade 1 Aquifer.
Source: Propump Engineering Ltd (n.d.)
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24.  Infill with Foamed Concrete (600,000 m3).
 Strength: 1MPa at Density: 600 kg/m3.
 Range of Consistencies (Rheology).
 Low Flow: Seal Fractures – Prevention of Leaching &
Contamination of Aquifer.
 Fluid: Ensure that all Crevasses are Filled.
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25.  Backfill of Sewer Trenches in Roadway.
 Strength: 4MPa, Denstiy: 1100 kg/m3.
 Cheaper to Place than Granular Fill.
 Self Compacting.
 No Skilled Operators.
 No Specialist Machinery.
 No Recurrent Repairs.
 Fast Curing: Resurfacing
possible the next day.
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26.  Small Quantities.
 Trench Reinstatement.
 Sarsfields Road Roundabout Flyover.
 Poor Soil Conditions: Cannot be Loaded.
 Excavation & Infill with Foamed Concrete Considered.
 Problematic Excavation: Low Shear Strength
 Vibro Concrete Columns & Skin Friction Piles Used.
 Similar Situations Countrywide.
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27.  Main Advantage:
 Low weight: Low Vertical Stresses Imposed.
 Rigid Material: No Lateral Earth Pressures.
 Variation in Mixes Available
 Strength/Density.
 Suitable for many tasks.
 Environmentally Friendly
 Recycles waste material (PFA, GGBS).
 Reduced energy consumption & emissions.
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28.  Academic Supervisor: Dr. Michael J. Creed.
 Mr. Frank Maguire, RPS Consulting Engineers.
 Dr. Yong Song Fan.
 Mr. Anthony M. Moloney.
 Staff at Inter-Library Loan Department, Boole
Library, UCC.
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29.  Thank You for Your Attention.
 Please feel free to:
 Ask Questions
 Voice Queries
 Provide Valued Constructive Criticism/Feedback.
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