Canadian Geotechnical Journal, Ahead of Print.
The majority of offshore wind structures are supported on large-diameter, rigid monopile foundations. These piles may be subjected to scour due to the waves and currents that causes a loss of soil support and consequently decreases the pile capacity and system stiffness. The results of numerical models suggest that the shape of the scour hole affects the magnitude of pile capacity loss; however, there is a dearth of experimental test data that quantify this effect. This paper presents a series of centrifuge model tests on an instrumented model pile that investigates the effects of scour-hole geometry on the response of a laterally loaded pile embedded in sand. The pile instrumentation allowed load–displacement and p–y (soil reaction – displacement) curves to be derived. Three scour geometries (global, local wide, and local narrow) and three scour depths (1D, 1.5D, and 2D; where D is pile diameter) were modelled. For all three scour types, pile moment capacity decreased almost linearly with increase of scour depth. Simple empirical relations were proposed to evaluate the detrimental influence of scour on the pile moment capacity. A new method has been developed to allow designers to quantify the effect of scour-hole shape and severity of scour on the pile response.

中文翻译：

---

冲刷对风力机单桩侧向阻力的影响：实验研究

加拿大岩土工程杂志，提前印刷。
大多数海上风电结构支撑在大直径刚性单桩基础上。这些桩可能会受到波浪和水流的冲刷，这会导致土壤失去支撑，从而降低桩容量和系统刚度。数值模型结果表明，冲刷孔的形状会影响桩容损失的大小；然而，缺乏量化这种影响的实验测试数据。本文介绍了对仪器模型桩进行的一系列离心模型试验，研究了冲刷孔几何形状对嵌入沙中的侧向荷载桩响应的影响。桩仪器允许推导出载荷-位移和 p-y（土壤反应-位移）曲线。三种冲刷几何形状（全局、局部范围、和局部狭窄）和三个冲刷深度（1D、1.5D 和 2D；其中 D 是桩直径）被建模。对于所有三种冲刷类型，桩弯矩能力随着冲刷深度的增加几乎呈线性下降。提出了简单的经验关系来评估冲刷对桩弯矩承载力的不利影响。已经开发出一种新方法，允许设计人员量化冲刷孔形状和冲刷严重程度对桩响应的影响。