Finite Element Analyses of Soil-Pipe Behavior in Dry Sand under Lateral Loading

Permanent ground deformations associated with earthquakes, liquefaction and landslides can introduce substantial axial and bending strains on buried pipeline systems. The analysis of the strains is largely dependent on the force imposed on the pipeline by relative displacement between the pipeline and surrounding soil. To advance state-of-the-art for soil continuum models, it is necessary to develop better simulation of soil-pipeline interaction. In this study, finite element analyses (FEA) of the soil-pipe interactions under lateral movement in dry sand are investigated. Mohr-Coulomb strength parameters applied in FEA are developed from direct shear test data and a subroutine was introduced to represent strain softening. The results show excellent agreement with large-scale 2D experimental results and the results are used to construct a dimensionless chart for various depth-to-diameter ratios for dry sand. The favorable agreement between analytical and experimental results marks a transition from characterizing engineering behavior through experimental results to characterizing that behavior on the basis of computational simulation. The guideline based on experimental results for estimating force induced by soil-pipeline interaction can be replicated with FEA.