海底滑坡对海洋单桩冲击力试验研究

为了研究海底滑坡对海洋单桩的冲击力大小,首先通过调整高岭土、粉砂的不同含量,得到不同流变特性、不同密度的碎屑流,采用Herschel-Bulkley模型和幂率模型对流体流变性质进行描述;随后利用自制海底滑坡模型槽,模拟碎屑流在不同流速和黏度下对模型桩的冲击;并结合流体力学理论,建立阻力系数与非牛顿流体雷诺数之间关系表达式。试验数据表明:碎屑流黏度和流速是影响海底滑坡冲击力的主要因素,海底滑坡冲击力随着泥浆黏度和流速的增加而增大。同时,考虑碎屑流剪切稀释特性,得到管桩阻力系数随雷诺数变化的拟合公式,为海洋桩基础设计提供参考。

Experimental study of submarine landslide impact on offshore wind power piles

In order to analyse the magnitude of debris flow impact forces on offshore wind power piles, we adjusted the contents of Kaolin clay and sand to generate debris flows with different rheological properties and densities. The rheological properties of debris flows were described by H-B model and power rate model. At different flow rates and viscosities, the impact of debris flow on model piles was simulated by using a self-made submarine landslide model flume. Based on the theory of fluid mechanics, the relationship between the drag coefficient and the Reynolds number of non-Newtonian fluids was established. The results show that the viscosity and flow velocity of the debris flow are the main factors affecting the impact of the submarine landslide, and the impact force of submarine landslide increases with the increase of debris flow velocity and the viscosity. Considering the shear thinning of the debris flow, the fitting formula of the pile resistance coefficient varying with the non-Newton Reynolds number was obtained to provide a reference for the design of the submarine pile foundation.