Numerical Study of Traction at Grouser–Soft Seabed Interface Incorporating Experimentally Validated Constitutive Model

Abstract

This paper presents the tractive performance of different grouser shapes in extremely soft seabed soil using finite element analysis (FEA). Consequently, the deformation characteristics and pattern of shear failure in the seabed soil can be predicted, eliminating expensive full-scale experiments. A three-dimensional FEA with the incorporation of geometric nonlinearity of shear rheometry is performed using coupled Eulerian–Lagrangian (CEL) technique in ABAQUS Explicit. The Mohr–Coulomb criterion is used to define the constitutive behaviour of the seabed soil sample used. To validate the model, the CEL simulation results are corroborated with experimental observations. The study reveals that the Mohr–Coulomb model with the governing parameters is able to capture the maximum rotational moment obtained from the experimental results with a maximum error of 3.5%. The Mohr–Coulomb model is therefore used to determine the maximum traction developed from two distinct grouser profiles to evaluate their tractive efficiency. It is observed that a triangular grouser offers better traction than an involute grouser.