Undrained Capacity of Suction Piles Subjected to Moment Loading

Abstract

In this study, undrained capacity of suction piles subjected to moment loading is examined using three-dimensional finite element analysis. The model was initially validated against well-established results in literature. The model was then used to investigate the effect of moment loading on vertical and torsional capacity by performing a sensitivity analysis by varying soil heterogeneity and suction pile geometry. The parametric study was carried out for suction piles with length to diameter ratios (L/D) varying from 1 to 7 embedded in soils with constant and linearly varying shear strength. The failure envelopes presented provide a better understanding and a simpler and quicker design method that can be readily used for the design of suction piles.

Undrained capacity of circular shallow foundations on two-layer clays under combined VHMT loading

“…The undrained soil Poisson’s was taken to be 0.495. Since the soil Young’s modulus, E u , affects only the evolution of the load-displacement relationship but not the calculated collapse loads (Yun and Bransby, 2007), a sufficiently large E u / s u0 ratio equal to 10,000 was selected to minimize mesh distortion (Abyaneh et al, 2015). The foundation was assumed to be a rigid body, and a load reference point (LRP) was used to apply prescribed displacements or loads, located at the bottom center of the foundation.…”

“…Similar to the horizontal capacity, the torsional capacity is also determined only by the surface soil strength, therefore, the T-V failure envelopes share similar features with increasing s u0 /s ut and t c /D to the H-V envelopes. The analytical equations proposed by Feng et al (2014) (see equation ( 7)), Abyaneh et al (2015) (see equation ( 8)) and Feng et al (2015) (see equation ( 9)) are compared to the FE results in Figure 10b and 10d. The comparison shows that the formula of Abyaneh et al (2015) gives reasonable and conservative predictions for the normalized failure envelope.…”

“…The analytical equations proposed by Feng et al (2014) (see equation ( 7)), Abyaneh et al (2015) (see equation ( 8)) and Feng et al (2015) (see equation ( 9)) are compared to the FE results in Figure 10b and 10d. The comparison shows that the formula of Abyaneh et al (2015) gives reasonable and conservative predictions for the normalized failure envelope.…”