Erosional behavior of sandy soil stabilized with alkali-activated municipal solid waste incineration bottom ash and industrial by-products

This study explores the potential of alkali-activated binders formulated from municipal solid waste incineration bottom ash (BA), waste kaolin (WK), and red mud (RM) for the sustainable stabilization of sandy soil. The objective is to develop an eco-efficient method that enhances mechanical strength and dual-mode erosion resistance while valorizing industrial by-products. Cylindrical specimens containing 10% BA with 10% WK or RM achieved unconfined compressive strengths (UCS) of 3300 kPa and 3000 kPa, respectively, whereas the untreated soil showed negligible strength. Erosion performance was evaluated through simulated rainfall (30–120 mm/h) and wind tunnel tests (7–28 m/s). Treated samples exhibited more than 99.9% reduction in rainfall and wind-induced erosion, with erosion losses decreasing from 1193.9 kg/m 2 to 0.206 kg/m 2 and from 659.2 kg/m 2 to 0.994 kg/m 2 , respectively. Penetrometer tests confirmed substantial surface hardening (up to 90 N) due to the formation of dense geopolymeric gels (C–A–S–H, C–S–H, and N–A–S–H). The findings demonstrate that integrating BA with WK or RM provides a technically viable and environmentally sustainable approach for soil stabilization and erosion control in vulnerable geomaterials.