| dc.description.abstract | Due to that Taiwan possesses the long and narrow terrain and has very high density of population, offshore wind turbines should be developed along the coast line. Considering that western Taiwan’s long coast line and its comparatively higher wind velocity than that of inland area, it is essential to consider the horizontal ultimate load, horizontal displacement of pile, rotating angle together with the maximum bending moment into the design of pile foundations. In this study, the geotechnical centrifuge facility at NCU is used to conduct a series of centrifuge mode test on the offshore wind turbine mono-pile. The mono-pile subjected to a horizontal force to investigate the corresponding acts of a mono-pile while affected by horizontal pushover.
In this research, the pile foundation of Denmark’s offshore wind farm is used as the model in designing pile foundation model. First, 40% of its original size is reduced, and then the reduced model is scaled down in accordance with the scale rule, which is later on been put in centrifugal field of 80g for testing in which the researcher applies pressure regulating valve to control air pressures to apply the horizontal force to the pile. During the process, the researcher measures the horizontal displacement of pile, the distribution of bending moment along depths with its corresponding horizontal force and applies regression analysis to get the changes of shearing force of pile(V), coefficient of soil reaction(p), rotating angle of pile(θ) and last, of displacement of pile.
The test results reveals that the pile embedded in the saturated sand bed will cause more displacement than that in the dry sand bed under the same magnitude of horizontal force. And, the further the pushover applies to the pile, the greater the bending moment on the pile. As a result, the pile suffers the greater bending moment and the greater pile horizontal displacement. The testing outcome of the p/D-y curves on the pile measured from both the dry sand bed and the saturated sand bed we can conclude that increase in the depths would increase the soil reactions at the same horizontal displacement of pile head. | en_US |