Analysis of Suction Caisson Capacity in Clay

Abstract

The paper addresses analysis techniques and design parameters for suction caissons in clay for loading conditions ranging from horizontal to vertical. A three-dimensional upper bound approach is described for caissons undergoing significant horizontal motion or rotation, and the relative accuracy of the analysis is assessed through comparison with independent semi-analytical 3-dimensional finite element analyses. For vertical loading, design parameters for shaft friction and end-bearing are deduced from results of physical model tests, for both sealed and unsealed caissons and for short-term and long-term loading. Interaction between horizontal and vertical loading is discussed, and aspects such as strength anisotropy of the soil, mis-alignment of the caisson (vertically and in plane), and orientation of the applied load are considered.

Effect of Gapping on the Transient and Sustained Uplift Capacity of a Shallow Skirted Foundation in Clay

“…Clukey et al (1995) report results from a centrifuge study of the eŠect of gapping on the capacity of suction caissons in typical Gulf of Mexico normally consolidated soft clay under cyclic loading, but did not observe a critical load at which the caisson suddenly failed from gapping. Randolph and House (2002) considered the sustained uplift capacity of suction caissons through analytical studies validated against beam centrifuge tests in normally consolidated clay and recognised the possibility of a hydraulic leak down the side of the caisson, due to slight tilting during cyclic loading, that may allow tensile fracture at the caisson base. For this case, they proposed an intermediate mode of failure, between pure shearing along the skirt and the full reverse end bearing.…”

Installation Constraints of Suction Assisted Foundations and Anchors for Offshore Energy Development

“…However, despite these installation issues, suctions caissons are more widely used in clay soils (66%) among all other soil types. [13], [18], [19], [ …”

“…The risk of misalignment of the caisson during installation could affect the load-bearing capacity of the caisson due to the uneven load distribution because of either the improper levelling of the caissons after touch down, buckling of the caisson, or attaching the steel chain or mooring lines to the padeye above or below the optimal position [12], [18].…”

Study on the Capacity Degradation of Bucket Foundation in Liquefied Sand Layer under Cyclic Loads~!2009-07-18~!2009-08-23~!2010-02-02~!

“…Despite several studies about static capacity and stability in subsiding for bucket foundations have been done [1][2][3][4], the long-term bearing capacity of bucket foundation under cyclic loads has not clarified. Several approaches to evaluating soil bearing capacities under cyclic loads [5][6][7][8][9] supply good reference for us.…”

“…The inner size of the model box is 600mm 350mm 350mm. The fine sand is adopted in experiments whose specific gravity is 2.69, the average diameter is 0.14mm, and the permeability coefficient is 4 5 10 cm/s. The layout of centrifugal model is shown in Fig.…”