Simulation of Soil-Structure Interaction with Sheet Pile and Retained Soil-Paper

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This study examines how soil–sheet pile interaction affects the behavior of anchored excavation support and compares two- and three-dimensional finite element models.<br /><br />The authors model a sheet pile wall as an elastic structural liner and represent the surrounding soil as sand over medium clay, using a Mohr–Coulomb plasticity model. Joint elements between the wall and soil allow relative slip. Their material-dependent interface coefficient scales the interface strength according to the surrounding soil properties. Excavation is simulated in three stages, with anchors installed as excavation progresses. The analyses include a 2D model, a plane-strain-like 3D thin-slice model, and a fully extruded 3D model.<br /><br />The 2D and thin-slice 3D models show close agreement when the interface coefficient is 1, with maximum displacement of approximately 0.091 m. Lower coefficients permit more slip, increasing wall displacement and the wall’s bending-moment and axial-force demands. The fully extruded 3D model produces displacement patterns similar to the 2D model, although its reported vertical and horizontal displacements are higher: 0.10 m and 0.088 m, respectively, compared with 0.091 m and 0.053 m in 2D. At very low interface strength, the models fail to converge, attributed to interface failure and separation between the wall and soil.<br /><br />The study demonstrates that an interface element can efficiently represent slip and that wall response depends on the degree of soil–structure interaction, not solely on earth pressure. However, the interface behavior is linear, and the approach lacks experimental validation. The authors recommend empirical studies to validate the method and establish suitable interface values for different soils and applications.

Keywords

soil-sheet pile interaction

anchored excavation

finite element model

sheet pile wall

Mohr-Coulomb plasticity

interface element

soil-structure interaction

bending moment

axial force

3D modeling