INFLUENCE OF FINES CONTENT ON SHEAR STRENGTH OF GRANULAR LAYERS

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INFLUENCE OF FINES CONTENT ON SHEAR STRENGTH OF
GRANULAR LAYERS

• By
• Lutfi Raad
• University of Alaska Fairbanks

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Main Objective

• Determine of material source and fines content on
  loss of shear strength upon freezing and thawing

3
Materials

• D1 Base
• Elliot Highway Base
• Marginal Sub-base
• Typical Moraine
• Sand
• Silt

4
Laboratory Tests

• Compaction
• CBR
• Percometer

5
Analysis

• Illustrate the influence of strength loss on
  pavement life (fatigue)
• Mechanistic methods

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Beginning Formation of Potholes
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Progression of Potholes
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Frost Heave Mechanisms
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Frost Heave Potholes
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Fatigue Cracking
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Grain Size of D1 Base
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Grain Size EH Base
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Grain Size New Marginal
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Grain Size - Moraine
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Grain Size - Sand
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Grain Size - Silt
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Soil Compaction Set-Up
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Compaction D1
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Compaction Marginal Subbase
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CBR Test Set-Up
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Freezing Specimens
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Specimen Soaking and Thawing
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Sample Conditioning PM Tests
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Sample Conditioning PM Tests
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Percometer Testing
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PM Tests - Moraine
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PM Tests - Silts
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Loss of Strength after F/T
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Strength Loss for Different Materials
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Loss of Strength with Fines Content
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80psi
2
Asphalt Concrete
Base/Subbase Course
15
Subgrade
32
Fatigue Behavior with CBR of Base