The use of stabilized soft clay as subgrade filling material has garnered significant attention in recent years for the effective management of engineering spoil. Nonetheless, under moisture change conditions, the hydro-mechanical performance of embankments constructed with treated soil remains uncertain due to the lack of field monitoring data. This study presents two years of monitoring data from a large-scale instrumented embankment model built with chemically stabilized soft clay. The hydrological and mechanical responses of the embankment were evaluated under two fluctuating moisture conditions: seasonal variation and a rising water table. The findings revealed that the maximum accumulated vertical strain of the embankment during the observation period was below 0.1%, which is considered acceptable for Chinese highway subgrades, thereby supporting the feasibility of employing soft clay in subgrade construction. The relationship between water content and suction in the embankment differed from that typically seen in fine-grained materials, displaying characteristics more similar to coarse-grained soils due to the stabilization effects. Additionally, the stabilization process mitigated particle displacement during suction changes, resulting in reduced embankment deformation compared to non-stabilized soil slopes. Significant deformation was observed when suction decreased to 60 kPa or when changes in horizontal earth pressure increased up to 15 kPa. These conditions corresponded to a degree of saturation of 70%, indicating that the wetting process below this saturation level in embankments constructed with stabilized soft clay necessitates greater attention in engineering applications. • A large-scale chemically stabilized soft clay embankment was built and monitored. • Hydro-mechanical behavior under two levels of variations in moisture was reported. • Chemically stabilized soft clay showed the soil-water characteristic curves (SWCC) mirroring coarse-grained soils. • More deformations occurred in the wetting path before the saturation level up to 70%.
Wang et al. (Sun,) studied this question.