Airfields and Pavements to Support Force Projection 622784AT40

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Airfields and Pavements to Support Force
Projection 622784/AT40
Advanced Analytical Model Development
Donald M. Smith, Ph.D., P.E.
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Development of AdvancedAnalytical Model for
PavementsMajor MilestonesFY01-02

• FY01 Milestones
• Integrate Cohesive Soil Model into FEM
• Develop AC Model for FEM Analysis of Pavements
• Develop Joint and Slab Models for JPCCP
• FY02 Milestones
• Integrate Environmental Effects into FEM System
  Model
• Integrate Performance Simulation into System
  Model
• Develop Long Term Surfaced Pavement Behavior
  Models
• Verify Systems Analysis Model (HVS, etc.)
• Develop Behavior Models for Pavement Layers and
  Systems

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Development of AdvancedAnalytical Model for
Pavements

• Phases
• Development of Constitutive Models
• Development of Model/Mesh Generation Interfaces
• Development of Geometric Modeling Tools
• Development of Performance Prediction
  Capabilities
• Flexible, Rigid, and Unsurfaced Pavements
• Non-Linear and Time Dependent Materials
• Joints, Layer Interfaces
• Multiple-Wheel Interactions
• Repeated Moving Loads
• Verified by Field Data

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Development of AdvancedAnalytical Model for
Pavements

• Phases
• Development of Constitutive Models
• Development of Model/Mesh Generation Interfaces
• Development of Geometric Modeling Tools
• Development of Performance Prediction
  Capabilities
• Team
• Don Smith PI, Systems Modeling, Calibration
  Tests, Materials
• John Peters Constitutive Model Formulation and
  Development
• Ernest Berney Subgrade Models, Calibration
  Tests
• Wayne Hodo AC Model Calibration/Verification
  Tests
• Ron Wahl Rigid Pavements, Systems Modeling
• Reed Freeman Field Verification Tests,
  Simulation

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Multi-Mechanical Constitutive Model Concept
e

• Mechanistic interpretation of endochronic model
• Simple implementation and calibration
• Captures history effects
• Consistent with traditional critical state
  concepts
• Based on effective stress

Elastic Elements
Plastic Elements
Parallel array of elastic and plastic elements
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Multi-Mechanical Constitutive Model for Granular
Materials Matsuoka Failure Surface I1I2/I3
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Multi-Mechanical Constitutive Model for Granular
Materials Calibration
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single element FE results
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Analytical Validation
C 130 tire 30,000 lbs _at_ 68 psi
Subgra
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Analytical Validation
C-130 Tire _at_ 68psi Deformation X 100
SHEAR STRAIN CONTOURS
1st Load Removed
Model Under 1st Load
Permanent Shear Strain
Model Under 5th Load
5th Load Removed
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Multi-Mechanical Constitutive Model for
Partially Saturated/Cohesive Soils

• Shrink/Swell behavior will be housed within
  Wetting element, Mw

• Model elements are functions of Saturation
• Strength
• Stiffness
• Critical State / Volume-
• Change Parameters
• Volumetric response relationships for varying
  water contents

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Multi-Mechanical Constitutive Model Concept as
Adapted for Viscoelastic Asphalt Material
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Multi-Mechanical Constitutive Model Concept as
Adapted for Viscoelastic Asphalt Material
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Elasto-Viscoplastic Response of Asphalt Mixture
A- Start of initial loading
B
B Yield point
D
C
C - Relaxation
D Relaxed yield stress
A
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Development of AdvancedAnalytical Model for
Pavements

• Phases
• Development of Constitutive Models
• Development of Model/Mesh Generation Interfaces
• Development of Geometric Modeling Tools
• Development of Performance Prediction
  Capabilities
• Flexible, Rigid, and Unsurfaced Pavements
• Non-Linear and Time Dependent Materials
• Joints, Layer Interfaces
• Multiple-Wheel Interactions
• Repeated Moving Loads
• Verified by Field Data

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Pavement Model Generation Interface

• Main Form Defines
• Landing gear configuration
• Location of the gear on the model
• How big the pavement section is
• Boundary conditions
• How to generate the mesh

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Advanced Analytical Model Development Rigid
Pavement Modeling
Single Slab 2 Layers
9 Slabs 2 Layers
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HVS Test Section with B52 Gear
Base Course Deflected Shape
Plan View Vertical Deflection Surface of
Pavement Top of Subgrade
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Advanced Analytical Model Development
Constitutive Model
Analysis Tools
Lab Tests
Application

• Flexible, Rigid, and Unsurfaced Pavements
• Joints, Layer Interfaces
• Multiple-Wheel Interactions
• Repeated Moving Loads
• Verified by Field Data
• More Realistic

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EndofPresentation