Numerical investigation to contribution of peripheral skirt and frame on undrained capacity of framed-tripod hexagonal bucket foundation in clay

The tripod bucket foundation (TBF) has become a well-established form of foundations in offshore engineering. Based on the traditional TBF, this paper innovatively proposes a tripod hexagonal bucket foundation (THBF), and presents a three-dimensional FE systematically investigates the uniaxial bearing capacity of the THBF, and explores the effects of bucket spacing, embedment depth, the different kinds of loading and soil strength heterogeneity. The loading bearing performance of THBF is compared with TBF in conjunction with displacement contours and the superiority of THBF in terms of uniaxial bearing capacity is demonstrated by the multiplicative relationship between the two. The multiplicative relationship between the uniaxial bearing capacity of the two is elucidated. In particular, a special failure mechanism for THBF under horizontal loading is also found. The modified form of adding the frame is innovatively proposed on the basis of THBF, which develops it into the framed-tripod hexagonal bucket foundation (F-THBF) with stronger performance, and the contribution from the frame between each bucket foundation to the bearing performance is evaluated, which provides a technical basis for further popularization and application of THBF and F-THBF.