Foamed lightweight soil (FLS) is frequently used for roadbed backfilling; however, excessive cement use contributes to higher costs and energy consumption. Desulfurized gypsum (DG), a by-product of industrial processing with a chemical composition similar to natural gypsum, presents a viable alternative to cement. This study evaluates the potential of DG to replace cement in FLS, creating a new material, desulfurized gypsum foamed lightweight soil (DG-FLS). This article is conducted on DG-FLS with varying DG content (0-30%) to assess its flowability, water absorption, unconfined compressive strength (UCS), durability, and morphological characteristics, with a focus on its suitability for roadbed backfilling, though its performance over the long term in engineering applications was not evaluated. Results show that as DG content increased, flowability, water absorption, and UCS decreased, with values falling within the range of 175-183 mm, 8.24-12.49%, and 0.75-2.75 MPa, respectively, all of which meet embankment requirements. The inclusion of DG enhanced the material's plasticity, improving failure modes and broadening its applicability. Durability tests under wet-dry and freeze-thaw cycles showed comparable performance to traditional FLS, with UCS exceeding 0.3 MPa. Additionally, the incorporation of SO42- in DG-FLS reduced sulfate diffusion, decreased C-S-H content, and increased calcium sulfate content, improving sulfate resistance. After 120 days of exposure to sulfates, the durability coefficient of DG-FLS surpassed 100%, with a 25% improvement over traditional FLS. A sustainability analysis revealed that DG-FLS not only meets engineering strength requirements but also offers economic and environmental benefits. Notably, DG-12 showed a 20% reduction in environmental impact compared to conventional FLS, underscoring its potential for more sustainable construction.

来源平台：ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING