The strength and hydraulic conductivity characteristics of sewage sludge ash and natural soil mixtures - a sustainable alternate landfill liner material
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View abstract on PubMed
Summary
This summary is machine-generated.Natural soil mixed with sewage sludge ash (SSA) shows potential as landfill liners. Optimal strength with minimal hydraulic conductivity increase is achieved with 3% SSA content.
Area Of Science
- Geotechnical Engineering
- Environmental Engineering
- Waste Management
Background
- Landfill liners are critical for environmental protection.
- Sewage sludge ash (SSA) is a potential pozzolanic material for soil improvement.
- Investigating SSA-soil mixtures for sustainable landfill liner applications is needed.
Purpose Of The Study
- To assess the feasibility of natural soil and SSA mixtures as landfill liners.
- To investigate the impact of SSA content on the hydraulic conductivity and strength of soil.
- To determine the optimal SSA content for landfill liner applications.
Main Methods
- Laboratory testing of natural soil and SSA mixtures.
- Measurement of hydraulic conductivity (hydrodynamic diffusion coefficient).
- Soil triaxial tests to evaluate strength characteristics (initial tangent modulus, ultimate principal stress).
Main Results
- Increasing SSA content generally increases both hydrodynamic diffusion coefficient and strength.
- A minor increase in hydrodynamic diffusion coefficient was observed for SSA content up to 5%.
- Significant enhancements in initial tangent modulus and ultimate principal stress were noted with SSA inclusion, with optimal performance at higher SSA content.
Conclusions
- Mixtures containing 3% SSA demonstrate a significant strength enhancement with only a marginal increase in hydrodynamic diffusion coefficients.
- The study suggests that natural soil mixed with 3% SSA is suitable for landfill liner applications.
- This research supports the use of SSA as a sustainable additive in geotechnical engineering for waste containment.
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