新型旋转减冲装置对桩基局部冲刷防护试验研究

Experimental study on local scour protection of pile foundationsby a new rotary scour guard

为减轻海上风电单桩基础周围局部冲刷对其结构安全的影响,本文提出了一种新型旋转减冲装置。在波流水槽中开展物理模型试验,改变波流条件、装置安装高度、安装距离,记录桩周冲刷发展历时,运用激光地形仪扫描冲刷坑形态,分析各工况下冲刷坑形态差异,验证装置不同安装距离、安装高度下的冲刷防护效果,提出了不同安装位置下的防护效率公式。结果表明:新型旋转减冲装置具有较好的冲刷防护效果,本试验工况下,桩周最大冲刷深度可减小44%左右。装置安装距离对冲刷防护效果影响较小,波流作用下的冲刷防护效果受装置安装高度影响显著,冲刷防护效果随装置安装高度的增加而减弱。

In order to mitigate the effects of local scouring around offshore wind monopile foundations on their structural safety,a new rotary scour guard is proposed.Physical model tests were carried out in the wave flow flume.The development of the scour process and scour depth around the pile were recorded under various waves,flow velocities,different installation heights and distances.A laser scanner was used to measure the topography of the scour hole.The differences in scour pit patterns under various operating conditions were analyzed to verify the scour protection effect of the device at different installation distances and heights.The results show that the new rotating scour guard has a good protective effect and the maximum scour depth around the pile can be reduced by about 44%under the present test conditions.The installation distance of the device has little influence on the erosion protection effect.The anti-scouring effect of the combined wave and current action is strongly influenced by the installation height of the equipment,which decreases as the installation height increases.