Study on static and dynamic mechanical behavior of expansive soil modified by oyster shell powder
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View abstract on PubMed
Summary
This summary is machine-generated.Oyster shell powder (OSP) enhances expansive soil properties. Finer OSP significantly increases cohesion and stiffness, improving soil stability for engineering applications.
Area Of Science
- Geotechnical Engineering
- Soil Mechanics
- Materials Science
Background
- Expansive soils pose significant challenges in civil engineering projects due to their volume change behavior.
- Oyster shell powder (OSP) is a potential sustainable additive for soil modification.
Purpose Of The Study
- To evaluate the impact of oyster shell powder (OSP) on the static and dynamic properties of expansive soil.
- To analyze the microstructural changes in expansive soil modified with OSP.
Main Methods
- Triaxial shear tests were conducted on Ningming expansive soil modified with OSP.
- Dynamic triaxial tests were performed to assess cyclic loading behavior.
- Scanning electron microscopy (SEM) was used for microstructural analysis.
Main Results
- Effective cohesion increased by 15.4% (d_osp < 1 mm) and 32.8% (d_osp < 0.075 mm) compared to plain soil.
- Finer OSP (d_osp < 0.075 mm) reduced plastic strain and pore water pressure under cyclic loading, increasing stiffness.
- Coarser OSP (d_osp < 1 mm) showed opposite dynamic mechanical property trends.
Conclusions
- OSP effectively modifies expansive soil properties, with finer particles yielding more significant improvements.
- Particle size distribution, bonding, and cementation are key factors influencing modified soil behavior.
- Findings provide a basis for OSP application in expansive soil stabilization and constitutive modeling.
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