## 1 Introduction  
With the rapid expansion of road construction, there is a growing demand for embankment filling materials [1, 2]. Concurrently, significant engineering projects produce substantial amounts of excavated waste soil, posing challenges for disposal. Solidification technologies offer a viable solution to these issues. These treatment technologies not only make the best use of natural resources, but also reduce excavated waste soil and provide high-quality fill materials. Extensive research has been conducted to explore the feasibility of solidified soil as construction fill materials [3, 4]. [PERSON] et al. [3] found that cement and fly ash-stabilized sediment could meet the requirement of subbase materials in terms of unconfined compressive strength and resilient modulus. [PERSON] et al. [4] indicated that the shear strength of the solidified excavated soft soil increased with higher stabilizer content, and the solidified excavated soft soil exhibited excellent stability even after undergoing dry-wet cycles. Various laboratory experiments and field tests have demonstrated that the solidified soils could meet the specifications of fill materials, including the liquid limit, plastic limit, compaction, unconfined compressive strength, California bearing ratio, and resilient modulus. According to [PERSON] et al. [3], large amounts of hydration products, resulting from the hydration reaction, improve the bond strength between the clusters and soil particles. In addition, the cation exchange reaction (Ca\({}^{2+}\) replacing K\({}^{+}\)) contributed to larger clay particles, which lead to an increase in the friction angle between the clusters [5]. Compared with untreated soils, the cohesion and friction angles of solidified soils significantly increased due to the cementation bond [6]. According to [PERSON] and [PERSON] [7], the pond ash and cement solidified soils showed satisfactory strength, cohesion and stiffness. Therefore, the cohesions and friction angles of solidified soil are higher than those of conventional coarse fill or natural cohesion soils. [PERSON] et al. [8; 9] pointed out that the solidified soils incorporating fly ash and slag were suitable for backfilling railroad and road embankments in Serbia in terms of the strength and stiffness. According to [PERSON] et al. [10], the cement-solidified lead-contaminated soils could be reused as embankment fill materials in highway construction in terms of the contaminant leachability and strength properties. [PERSON] et al. [11] claimed that lime stabilization of clay soils, due to its economic and high performances, is becoming, if it is not already, one of the most used techniques construction for road and railway embankments. Solidified soils with industrial by-products, such as calcium carbide residue [12] and lignin [13], showed excellent performance, and could be used for highway subgrade. Lime-treated clay has been used as the upper subgrade fill for highways [14]. The cement-stabilized soil was used as embankment fill in the Beijing-Tianjin high-speed railway [15], while the deformation characteristics and load transfer mechanism of cement-solidified soil embankment were not studied. Pile-supported embankments have been widely applied in infrastructure projects [16]. A number of studies have been performed to investigate the soil-arching mechanism [17; 18; 19]. Due to the complexity of piled embankments, numerical modelling is considered an effective tool. The soil arching phenomenon in a pile-supported granular embankment was demonstrated based on the two-dimensional finite element modeling approach [20]. The large-scale physical model was also utilized to simulate the behavior of the piled embankment reinforced with the basal geosynthetic reinforcement [21]. However, in the literature review, most studies focus on the load transfer mechanism for coarse materials or cohesionless soils, and the effects of cohesion of embankment soils were not considered in pile-supported embankments [22; 23].