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Optimizing Soil Stabilization with Chitosan: Investigating Acid Concentration, Temperature, and Long-Term Strength
Runshen Wang1,2, Dominic E L Ong2,3, Hossein Sadighi4
1Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education, Hohai University, Nanjing 210024, China.
Polymers
|January 25, 2025
Summary
Chitosan biopolymer enhances soil strength, offering an eco-friendly alternative to cement. Optimal results were achieved with specific acid concentrations and temperatures, showing potential for geotechnical applications.
Area of Science:
- Geotechnical Engineering
- Materials Science
- Environmental Science
Background:
- Traditional soil stabilizers like cement have environmental drawbacks.
- Chitosan biopolymer shows promise for soil stabilization, erosion control, and heavy metal adsorption.
Purpose of the Study:
- Investigate chitosan's impact on soil strength using unconfined compression strength (UCS) and static triaxial testing.
- Determine optimal chitosan content, acid concentration, and temperature for soil improvement.
- Explore chitosan-treated soil for large-scale geotechnical applications.
Main Methods:
- Unconfined compression strength (UCS) tests to assess soil strength.
- Static triaxial testing to evaluate shear strength.
- Scanning Electron Microscopy (SEM) to analyze microstructural changes.
- Development of a chemical model to explain property variations.
Main Results:
- Chitosan significantly increased soil strength over time and with elevated temperatures (optimal curing at 45-65 °C).
- Optimal acid concentration for dissolving chitosan was found to be 0.5-1%.
- SEM revealed chitosan coating soil particles and filling voids, enhancing strength through hydrogen bonds and electrostatic interactions.
Conclusions:
- Chitosan biopolymer is an effective soil stabilizer, improving strength and potentially reducing environmental impact.
- Optimized conditions (acid concentration, temperature) are crucial for maximizing chitosan's soil-strengthening capabilities.
- Chitosan-treated soil shows significant potential for future geotechnical engineering applications.
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