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Updated: Aug 13, 2025
12:21
Determination of the Friction Coefficients of Icy Pavements Under Different Amounts of Snowfall
Published on: January 6, 2023
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The Stiffness Behavior of Asphalt Mixtures with Different Compactness under Variable Confinement
Hancheng Dan1, Penghao Yang1, Wei Cao1
1School of Civil Engineering, Central South University, Changsha 410075, China.
Materials (Basel, Switzerland)
|January 21, 2023
Summary
This study introduces a new lab method to test asphalt's dynamic modulus under realistic conditions. Coarser asphalt mixtures showed less sensitivity to temperature, frequency, and density changes.
Area of Science:
- Civil Engineering
- Materials Science
- Geotechnical Engineering
Background:
- The dynamic modulus of asphalt pavement is crucial for performance.
- Accurately simulating in situ stress conditions in labs is challenging.
- Confining pressure and material density significantly influence dynamic modulus.
Purpose of the Study:
- To develop a convenient experimental setup for confined dynamic modulus testing.
- To investigate the influence of temperature, frequency, and compactness on asphalt mixtures.
- To develop a mathematical model for the dynamic modulus master curve.
Main Methods:
- Developed a novel experimental setup to simulate lateral confinement during vertical loading.
- Prepared three dense-graded asphalt mixtures at four different densities.
- Conducted confined dynamic modulus tests and applied time-temperature superposition principle.
Main Results:
- Dynamic modulus significantly depends on temperature, frequency, and compactness.
- Coarser asphalt gradations exhibited reduced sensitivity to these factors.
- A mathematical model was developed and validated for the dynamic modulus master curve.
Conclusions:
- The developed model effectively unifies factors influencing dynamic modulus.
- The study provides insights into asphalt pavement performance and field compaction.
- Coarser mixtures offer potential advantages in pavement durability and stability.
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