Numerical Analysis of Pile-Supported Reinforced Embankments in Deep Soft Soil Regions Based on Soft Soil Creep Parameter Optimization

Abstract

When analyzing the engineering characteristics of pile-supported embankments in deep soft soil regions, the creep behavior of soft soils cannot be overlooked. In previous numerical analyses, empirical formulas were often used to determine related parameters, which limited the accuracy of the calculations. This study validated the reliability of the soft soil creep (SSC) model using measurement data and proposed an optimized process for SSC parameter selection, aiming to improve both accuracy and practical applicability. A numerical model was established based on actual engineering to study the effects of different pile lengths and spacing on settlement, soil arching, and reinforcement material stress. Key findings include as follows: (1) The SSC model outperforms the Mohr–Coulomb and soft soil models in predicting settlement and stress concentrations. (2) An optimized SSC parameter selection process is proposed, providing reference values for typical soft soils in Zhejiang, China. (3) Settlement increases significantly when pile spacing exceeds 2.8 m in this project, suggesting the existence of a threshold effect of pile spacing on settlement. (4) Increasing pile length reduces differential settlement and the tensile force on reinforcement material, with differential settlement decreasing from 0.268 to 0.114 mm and tensile force dropping from 106 to 89 kN/m as pile length increases from 24 to 30 m. This finding shows the importance of balancing pile length and reinforcement material strength, which can reduce project costs while ensuring the stability and quality of the embankment. This study provides a theoretical basis for the design of pile-supported reinforced embankments in soft soil regions.