Wind erosion control using alkali-activated slag cement: Experimental investigation and microstructural analysis

Area of Science:

• Soil Science
• Materials Science
• Environmental Engineering

Background:

• Wind erosion is a significant environmental problem causing soil degradation.
• Traditional methods for soil stabilization have limitations.
• Alkali-activated slag offers a novel approach for soil treatment.

Purpose of the Study:

• To evaluate the efficacy of alkali-activated slag in mitigating wind erosion of soil.
• To quantify the reduction in soil erodibility using alkali-activated slag.
• To investigate the crust strength and microstructural properties of treated soils.

Main Methods:

• Wind tunnel tests were performed on soil samples treated with varying percentages of alkali-activated slag.
• Erodibility was assessed under different wind speeds (7-28 m/s) and with sand bombardment.
• Crust strength was measured using penetrometer tests.
• Microstructural analysis was conducted using X-ray diffraction and field emission scanning electron microscopy.

Main Results:

• Soil erodibility significantly decreased with increasing alkali-activated slag content, reaching as low as 0.06% of untreated soil at 28 m/s wind speed.
• In the presence of sand bombardment, erodibility reductions ranged from 98.5% to 99.6%.
• Crust strength increased dramatically, 1300 to 6500 times greater than untreated soil.
• Formation of albite, anorthite crystals, and various hydrate gels (calcium aluminosilicate hydrate, sodium aluminosilicate hydrate, calcium silicate hydrate) was observed.

Conclusions:

• Alkali-activated slag is highly effective in reducing soil wind erodibility.
• The formation of robust crusts is the primary mechanism for erosion mitigation.
• This method provides a sustainable and efficient solution for controlling wind erosion and soil loss.