Sustainable soil stabilization: a comprehensive review of green technologies, industrial by-products, and bio-mediated methods

Soil stabilization is fundamental to geotechnical engineering, yet traditional cement- and lime-based methods impose significant environmental burdens through high energy consumption and CO 2 emissions. This review systematically analyzes sustainable stabilization technologies, including bio-mediated techniques (microbially induced carbonate precipitation [MICP] and enzyme-induced carbonate precipitation [EICP]), industrial by-product utilization (fly ash, ground granulated blast furnace slag [GGBS], steel slag, and cement kiln dust [CKD]), geopolymer and alkali-activated binders, and bio-based additives (biopolymers and plant root reinforcement). For each technology, the review presents fundamental mechanisms, engineering performance data, environmental benefits, and current limitations based on a systematic literature survey of 187 studies from 2010 to 2026. A novel multidimensional decision matrix mapping soil type, environmental exposure, and structural requirements to optimal stabilization technology is presented. Life cycle assessment (LCA) methodologies are discussed with cradle-to-gate and cradle-to-grave boundary analyses. Comparative evaluations of durability, cost-effectiveness, and carbon footprint reveal that geopolymer binders offer 60%–80% CO 2 reduction versus Portland cement, while MICP achieves near-zero direct emissions but remains limited by scalability constraints. Critical knowledge gaps include scalability challenges (95% of MICP studies remain bench-scale), long-term durability concerns, standardization needs, and insufficient field-scale validation. Future research directions emphasize hybrid stabilization systems, carbon-negative geotechnics, smart monitoring technologies, and circular economy integration. This review provides an evidence-based reference for researchers and practitioners seeking to adopt sustainable soil stabilization practices aligned with global decarbonization goals.