Experimental Study on Whole Wind Power Structure with Innovative Open-Ended Pile Foundation under Long-Term Horizontal Loading

Abstract

The offshore wind energy (OWE) pile foundation is mainly a large diameter open-ended single pile in shallow water, which has to bear long-term horizontal cyclic loads such as wind and waves during OWE project lifetime. Under the complex cyclic loads, the stress and displacement fields of the pile-soil system change continuously, which affects the dynamic characteristics of the pile foundation. Within the service life of the pile foundation, the pile-soil system has irreversible cumulative deformation, which further causes damage to the whole structure. Therefore, it is important to examine the overall dynamic characteristics of wind power foundation under high cycle. In this paper, in the dry sand foundation, taking the Burbo Bank 3.6 MW offshore turbine-foundation structure as the prototype, the horizontal cyclic loading model tests of the wind power pile foundation with the scale of 1:50 were carried out. Considering the factors such as loading frequency and cyclic load ratio, the horizontal dynamic characteristics of the whole OWE pile foundation are studied. The comparison results between the maximum bending moment of pile and the fitting formula are discussed. In conclusion, moment of OWE pile shaft is corresponding to the loading frequency (f = 9 HZ) and loading cycles by fitting formulas. The fatigue damage of the OWE pile does not occurs with low frequencies in high cycles.

Condition Diagnosis of Long-Span Bridge Pile Foundations Based on the Spatial Correlation of High-Density Strain Measurement Points

“…The deformation of pile foundations under vertical loading, lateral loading, and inclined loading has been studied [20][21][22][23][24]. The method for predicting the deformation of pile foundations has been widely studied [25][26][27], and a numerical model with greater load conditions and a wider range has been further developed [28][29][30][31][32]. The mechanical characteristics of pile foundations have been studied by many scholars, and the state of pile foundations can be judged by theoretical calculations and numerical models.…”

Experimental Data of Bottom Pressure and Free Surface Elevation including Wave and Current Interactions

“…Experimental force measurements help provide confidence in system design and are a crucial requirement for a wide range of ocean and coastal engineering problems. For instance, force measurements are used to quantify structural loading on breakwaters [1][2][3], as well as loading on complex systems, such as remotely operated vehicles [4][5][6][7], offshore wind turbines [8][9][10][11], sediment transport and bottom fluvial erosion [12,13] and tidal stream turbines (TSTs) [14][15][16][17][18]. To obtain vector force measurements experimentally, force plates are typically used and are integrated into the structure and/or foundation.…”