<p>Main chemical components of phosphogypsum.</p>

To address these limitations, this study proposes an environmentally sustainable binder termed LSP (lime-sodium silicate amended phosphogypsum) based on the valorization of phosphogypsum (PG). Systematic laboratory tests were conducted to evaluate the engineering performance of LSP stabilized soil under drying-wetting cycles.

Results indicate that the expansive soil stabilized with LSP obtains a higher maximum dry density and a lower optimum moisture content. The swelling-shrink potential is weakened as well. However, the successive D-W cycles imposes detrimental impacts on the development of all the geotechnical indexes, including free swelling index, unconfined compressive strength (UCS), shear strength, compressibility and permeability.