Numerical Modeling of Pile Groups Composed of Two Open-Ended Steel Piles

Abstract

Piles are often used as foundation elements to support different offshore structures founded by jacket foundation system, which consist mainly of space truss, supported in the four corners by driven steel piles. In each corner of the jacket construction, a single pile has to be driven through the pile sleeve. In the case of platforms with high vertical loads is could be favourable to use two piles which are closely placed to each other in each corner of the jacket. In this case, the expected pile group effect should be examined. This paper deals with the numerical modeling of pile groups composed of two open tubular steel piles embedded in mainly non-cohesive soil. A three-dimensional numerical model using the finite element system ABAQUS will be developed. In this model the material behaviour of the subsoil is described using an elasto-plastic constitutive model with Mohr-Coulomb failure criterion. Parametric studies will be done to investigate the structural behaviour under different conditions regarding the pile spacing. The results will be presented to examine the overall behaviour of pile groups.