Breaking Wave Loads on a Slender Pile in Shallow Water

Abstract

The load of breaking waves distinguishes from the impact of non -breaking waves in the superposition of an additional, transient force of short duration. A simple method is presented to decompose the quasi -static force, the periodic part of the total measured force, and the dynamic component, which is the response of the cylinder due to the additional impact. The method is verified with large-scale model tests. The tests were carried out in the Large Wave Channel (GWK) with a slender, vertical and inclined cylindrical pile located at the end of a 1:10 slope. Finally the impact and the curling factor λ, an empirical coefficient to calculate the height of the impact area, is determined and compared to published data from laboratory deep water experiments.

Global slamming forces on jacket structures for offshore wind applications

“…They should therefore be considered in the design of offshore wind turbines, as 10 recommended by various standards and guidelines [2, 3,4].…”

“…Due to the strong nonlinearities of slamming forces, small-scale experiments or fullscale field measurements seem to be the most reliable method to quantify them. 20 To date, several experimental studies of slamming forces on vertical or inclined slender cylindrical structures have been carried out [9,10,11]. An on-site measurement regarding the slamming loads has also been conducted for a monopile wind turbine at the Blyth wind farm [1].…”

“…Two common methods to achieve this goal are frequency domain filtering and Empirical Mode Decomposition (EMD) combined with filtering [10]. However, these methods overestimate the quasi-static part in the region of the maximum load [10], thus leading to underestimation of the dynamic part.…”

“…However, these methods overestimate the quasi-static part in the region of the maximum load [10], thus leading to underestimation of the dynamic part.…”

Numerical Simulation of Breaking Wave Loading on Standing Circular Cylinders with Different Transverse Inclined Angles

“…It was presented that the total breaking wave force is the sum of the quasi-static force calculated by the Morison equations and the slamming force considering the duration of the impact. Irschik et al [3] employed the Fast Fourier Transform (FFT) low-pass filter and the Empirical Mode Decomposition (EMD) to separate the experimental data of breaking wave forces on a vertical cylinder into two components, i.e., the quasi-static loading and the dynamic force. They found that the calculation methods overestimated the quasi-static force in the region of the maximum impact.…”