Numerical Assessment of Jackup Spudcan Foundations by varying Angle of Spud in 3d Fem in Geotechnical Engineering

Abstract

A jack-up structure is a bottom-mounted floating unit having an adjustable hull and movable legs. Particular jack-up structures are more susceptible to hazards under environmental loads during their operation and life cycle in the ocean. Authors attempted here to evaluate vertical load carrying capacity of soil and predicting its behaviour. Simulation of loaddeformation behavior under axial compression has been carried out for advancing research. The entire study has been carried out using three-dimensional finite element-based software Plaxis 3D A.E. 2017. The geometrical variation of substructure spud can have an inverted spud at the centre bottom from 1200 to 1800 studied for knowing behaviour under axial compression, axial tension and lateral forces. The simulated numerical model is used to develop empirical expressions for axial capacities estimation. The numerical analysis results indicate that spud can have an inverted angle of cone 1300 which is most beneficial under the static combined vertical, moment and horizontal loading (3D loading) in marine clay. The axial load carrying capacities in compression, tension and lateral loading follow the same sequence in ascending order from 1800,1750, 1500, 1300 and highest in 1200. Stiffness and undrained shear strength of soft clay contribute more than the diameter of the spud and embedment depth in compression and tension.