A simple implementation of RITSS and its application in large deformation analysis

Large deformation finite element (LDFE) analysis is being applied increasingly in geomechanics as it allows numerical interpretation of problems in which the structural element moves a relatively long distance through the soil. The 'remeshing and interpolation technique with small strain' (RITSS) method for LDFE analysis, in which the soil domain is periodically remeshed with the stress and material properties interpolated from the old to the new within the standard Lagrangian finite element framework, has been successfully applied to a number of practical applications. It allows any standard finite element theory to be used in the Lagrangian analysis, and because the mesh topography and connectivity are not influenced by the previous deforming increment, large deformations are possible. The major barrier of the RITSS method is that the remeshing and interpolation requires specialised and user-dependent computer code. This has limited its application to specialists and hindered its routine application in engineering practice. This paper proposes a simpler, more practical method to implement RITSS for geotechnical applications. By utilising the ABAQUS in-built procedures for interpolation and remeshing, it avoids any need for user-defined code (although a piece of Python script can be used to automate the iteration instead of operating the ABAQUS user interface). A series of four example problems benchmarking this new approach show it to be robust and numerically accurate. (C) 2013 Elsevier Ltd. All rights reserved.