Setup of axial bearing capacity of open ended tubular steel piles driven in sand

This paper focuses on the setup of axial bearing capacity of open ended tubular steel piles that are used for offshore foundation systems such as those of wind turbines. A comparative evaluation of the most commonly used models for setup prediction shows an upper estimate bound and a lower estimate bound, which correspond approximately to a setup rate of 60% increase per log cycle of time and 20% increase per log cycle of time, respectively. This finding is validated with the results of case histories reported in literature, which show that the setup values of most case histories considered lie in the best estimate zone between the upper estimate zone and the lower estimate zone. The analysis results show a minimum setup factor of approximately 1.5 for 100 days following end of driving of open-ended tubular steel pile driven in sand.