Numerical modelling of the keying process for a suction embedded plate anchor in spatially varying clays

Abstract

ABSTRACT As the exploration of oil and gas moves into deeper water, suction embedded plate anchors (SEPLAs) are developed to answer the growing demand for anchor-mooring systems. The keying process of SEPLAs has been extensively reported assuming a spatially homogeneous soil which is a departure from reality. This study conducts a comprehensive investigation of the keying process of SEPLA in spatially varying clay through a large deformation random finite element method coupled with the Monte Carlo simulations. The numerical model is validated with the results from the existing centrifuge test and numerical analysis. The spatial randomness of soil strength is assumed to be a three-dimensional (3D) random field to explore the failure mechanism and statistical characteristics of rotational response and pullout behaviour. The normalised factor of the upper 5% fractile of embedment loss is presented as an algebraic expression of the coefficient of variation of soil strength. The relationship between safety factor and failure probability is determined based on the requirement of pullout capacity. Finally, the applicability of the present results to different soil properties is verified.