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Method to Predict Salt Expansion Deformation in Cement-Stabilized Macadam Under Sulfate Attack Based on Pore
Xiangyu Li1, Xuesong Mao1, Pei He1
1School of Highway, Chang'an University, Xi'an 710064, China.
Materials (Basel, Switzerland)
|November 13, 2025
Summary
Cement-stabilized macadam experiences salt expansion due to sulfate attack. Its pore structure significantly influences this deformation, leading to a new predictive model for material performance.
Area of Science:
- Civil Engineering
- Materials Science
- Geotechnical Engineering
Background:
- Cement-stabilized macadam is susceptible to salt expansion deformation under sulfate attack.
- The pore structure of the material plays a critical role in its capacity to withstand this deformation.
Purpose of the Study:
- To analyze the influence of pore structure on the macroscopic deformation of cement-stabilized macadam under sulfate attack.
- To identify key factors contributing to salt expansion deformation.
- To develop a predictive model for salt expansion deformation.
Main Methods:
- Single-grain salt expansion deformation test.
- Scanning Electron Microscopy (SEM) for microstructural analysis.
- Computerized Tomography (CT) scanning for pore structure characterization.
Main Results:
- Ettringite and sodium sulfate decahydrate crystals are identified as primary drivers of salt expansion.
- Increased sulfate content (0-5%) led to decreased porosity (-1.5%) and increased primary pore proportion (+12.1%), correlating with a higher linear expansion rate (+0.05%).
Conclusions:
- Pore structure characteristics significantly impact the salt expansion deformation of cement-stabilized macadam.
- A predictive model incorporating porosity, pore distribution, and a deformation influence factor was developed with <10% error.
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