Improvement of Strength of Expansive Soil Using a Combination of Industrial Bagasse and Low-Alkali Ecological Cement

The article is based on the presentation at the international conference “Soil Mechanics and Geotechnics in High-Rise and Underground Construction,” which was held in honor of Prof. Z. G. Ter-Martirosyan (Moscow State University of Civil Engineering, September, 2024). Cement is commonly employed to address issues associated with the deformation behavior of an expansive soil, but it has drawbacks, such as increasing soil alkalinity and failing to effectively prevent soil cracking under dry–wet cycles after stabilization. Additionally, it negatively impacts the ecological environment and the strength of the treated soil. This study introduces an innovative approach using low-alkali ecological cement (LAEC) and industrial bagasse (IB), a by-product of sugar production, to stabilize expansive soil. Through dry–wet cycle tests, soil–water characteristic curve tests, and direct shear tests, the effectiveness of this method in controlling crack formation, soil-moisture movement, and shear-strength changes was evaluated. Compared with traditional Portland cement stabilization, the proposed method results in a soil pH more conducive to plant growth. The tubular structure of IB offers the flexibility to accommodate soil deformation and reduces crack development. Furthermore, the water-retention capacity of the soil treated with LAEC and IB is significantly enhanced. A combination of 1.2% IBand and 7% LAEC demonstrates the highest shear resistance, maintaining greater strength than untreated expansive soil, even after five dry–wet cycles.