Study on Mechanical Properties and Curing Reaction Mechanism of Alkali-Activated-Slag Solidified Port Soft Soil with Different Activators
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View abstract on PubMed
Summary
This summary is machine-generated.Alkali-activated slag (AAS) effectively solidifies soft soil using Na2O·nSiO2 as the optimal activator, enhancing mechanical properties for eco-friendly foundation curing.
Area Of Science
- Geotechnical Engineering
- Materials Science
- Environmental Science
Background
- Soft soil foundations pose engineering challenges due to low strength and high compressibility.
- Alkali-activated slag (AAS) offers an economical and environmentally friendly alternative for soil stabilization.
Purpose Of The Study
- To investigate the mechanical properties and strength formation mechanism of AAS-solidified soft soil using different activators.
- To determine the optimal activator type, amount, and slag powder content for soft soil improvement.
Main Methods
- Orthogonal experimental design to optimize AAS parameters (activator type, amount, slag powder content).
- Mechanical testing (unconfined compressive strength, resilience modulus, shear strength, compression modulus) of solidified soil.
- Microscopic analyses (SEM-EDS, TG-DTG, FT-IR) to elucidate strength formation mechanisms.
Main Results
- The order of influence on unconfined compressive strength was activator type > activator amount > slag powder amount.
- Optimal parameters identified: Na2O·nSiO2 activator, 3% activator amount, 20% slag powder.
- Na2O·nSiO2 activator yielded superior mechanical properties and early strength compared to NaOH and Ca(OH)2.
- Hydration products (C-A-S-H, N-A-S-H, C-S-H gels) contribute to increased soil strength and cohesion.
Conclusions
- Alkali-activated slag with Na2O·nSiO2 is a highly effective method for solidifying and improving soft soil foundations.
- The solidified soil exhibits favorable engineering characteristics, particularly with a 0.7-modulus Na2O·nSiO2 activator.
- AAS technology presents a sustainable and viable solution for soft soil stabilization in civil engineering applications.
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