Application of the SPH Finite Element Method to Evaluate Pipeline Response to Slope Instability and Landslides

Buried pipelines operating on active slopes can be subject to lateral and axial loads resulting from slope instability and landslides. The techniques to predict pipeline displacements, loads, stress or strains are not well described in design standards or codes of practice. Finite element analysis based soil-pipe interaction simulation has developed in recent years and is proving to be a useful tool in evaluating the pipeline behavior in response to slope movement. A description of the BMT pipe soil interaction modeling techniques, their validation against full scale trails and comparison to spring support models has been previously published. This paper describes the modeling techniques and demonstrates the application and versatility of the LS-DYNA 3D continuum SPH (Smooth Particle Hydrodynamic) model to evaluate pipeline behavior and pipeline strain demand. The effects of key parameters, including soil movement mechanism, pipeline geometry, material grade and soil conditions and properties are considered. The application and results presented in this paper are used to illustrate an advanced soil structure interaction numerical simulation technique combining the LS-DYNA nonlinear SPH formulation with Lagrangian formulation while satisfying all the principles of continuum mechanism . Keywords: LS-DYNA, SPH, soil-pipe interaction, slope movement, landslide, strain demand, strain relief, geo-hazards