Three-Dimensional Response of Buried Pipelines Subjected to Large Soil Deformation Effects: Part I—3D Continuum Modeling Using ALE and SPH Formulations

Abstract

Understanding the effect of soil-pipeline interactions in the event of large ground movement is an important consideration for the pipeline designer. Both experimental investigation and computational analyses play significant roles in soil-pipeline research. As part of this effort, a framework incorporating continuum soil mechanics and advanced finite element approach (i.e., ALE and SPH method) for modeling soil pipe interaction was constructed. The overall objective of this work is to develop, validate and apply 3D continuum modeling techniques to assess the performance of pipeline systems subjected to large soil displacements. The numerical models produced may subsequently be used to predict the wrinkle formation and post formation behavior of the pipeline considering the effect of the soil confinement. The aim is to develop a comprehensive wrinkle integrity assessment process. This is the first paper (Part I) in a series of two papers. In this paper a three-dimensional Continuum models using MM-ALE (Multi-material Arbitrary Eulerian Lagrangian) and SPH (smooth particle hydrodynamics) approaches are developed and employed using LS-DYNA. The results are compared with published experimental data of large-scale tests to verify the numerical analysis methods. In the second paper (Part II) the effects of soil restraint on the response of the pipe/soil systems (e.g., pipeline wrinkle and buckle, strain demand) are discussed.

Trends in large-deformation analysis of landslide mass movements with particular emphasis on the material point method

“…The operator-split ALE involves two stages: (a) Lagrangian step, where the governing equations for the saturated soil, the equilibrium equation and the continuity equation are solved by the traditional, updated Lagrangian method, and (b) the Eulerian step, which involves mesh smoothing and transfer of state variables. Many researchers have applied the ALE technique to solve geotechnical problems, which involve large deformations, such as a rough footing on an undrained soil layer (Nazem et al, 2009), consolidation problem (Nazem et al, 2008) and soilpipeline interactions (Fredj & Dinovitzer, 2010). Kardani et al (2011) implemented a refined h-adaptive finite-element technique in ALE to improve the numerical accuracy by continuously refining the mesh in the zone of concern.…”

Large deformation coupled analysis of embedded pipeline – Soil lateral interaction

“…However, for dynamic problems, the efficiency of the RITSS approach was reduced somewhat by the need for sufficiently small steps, comparable to those in CEL, thus negating the benefit of the implicit calculation approach. Other methods, e.g., the Smoothed Particle Hydrodynamics (SPH) [41][42][43], Material Point Method (MPM) [44,45], and Particle Finite Element Method (PFEM) [46,47], fall in the latter category.…”