Behavior of soil slopes reinforced with composite-structural piles

Abstract

Slope stability is a key problem in geotechnical engineering, often addressed through reinforcement methods, such as reinforced concrete piles. However, they have limitations, including high costs and underutilization of steel and concrete properties. This study proposes a new type of composite-structural pile, combining two types of materials with different mechanical behaviors. Centrifuge model tests were performed to explore the deformation and failure behavior of slopes reinforced with the composite-structural pile under vertical loading conditions. The strains and soil pressure of the composite-structural pile were measured to analyze its stress characteristics. The composite-reinforced slope exhibited progressive failure from the top to the toe under vertical loading conditions, featuring a curved, discontinuous slip surface. The slope deformation increased with increasing load and developed to deformation localization. A clear coupling effect was observed between slope deformation localization and local failure. Finite element analysis was performed to evaluate the mechanical characteristics of the composite-structural pile under bending conditions. The strain distribution on the cross-section of the pile was linear for different material parameters. Based on these findings, a method for calculating the stress and strain of composite-structural piles was developed. Centrifuge model tests validated the reliability of the proposed method.