Effect of Pile Bending Stiffness on Static Lateral Behavior of a Short Monopile in Dry Sand


1 Phd candidate, university of Tehran

2 Associate professor, university of Tehran

3 Assistant professor, university of Tehran


Monopiles are common foundations for offshore structures such as wind turbines and they are commonly used as fender piles in port structures. In such structures, especially in OWTs, the ratio of pile length to diameter (L/D) is small which makes the pile behave as a rigid structure. However, the pile flexural (bending) stiffness still affects the pile load-displacement characteristics and maybe should not be ignored in the pile design. In this study, the effect of pile flexural stiffness on a short monopile subjected to static lateral load is investigated.  The modeled pile has aspect ratio of 5 (L/D=5) which is driven into medium sand. The main characteristics of pile static lateral behavior including lateral resistance, stiffness, deflections, bending distribution and toe-kick are investigated and results are discussed. Results show that in the studied case, the pile behavior pattern is in the middle of flexible and completely rigid pile and therefore bending stiffness has meaningful effects on some important parameters related to monotonic performance.


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