摘要
近年来,全球海上风电发展势头迅猛.单桩基础作为最早应用于海上风电的基础类型,在全球风场中占据主导地位.现有风机的寿命一般约为20年,预计未来10年将迎来大量风机退役,这使得海上桩基础的回收问题变得愈发重要.为更好地解决海上桩基础退役拆除问题,本文通过物理模型实验的方式对注水加压拆除法进行了研究.实验结果显示:大直径桩基础拆除时所需压强更小,更易通过注水加压拆除法进行拆除;桩基础初始倾角对注水加压拆除所需压强影响较小,但初始倾角越大基础越易倾倒;拆除过程中桩基础单位位移引起的舱内压强下降幅度始终相同,不受基础直径、入泥深度以及倾角的影响.根据物理模型实验数据,结合土力学、水力学相关理论,建立了注水加压拆除法全过程理论模型,可大致预测不同桩径、不同入泥深度桩基础的启动舱内压强与舱内压强-位移曲线,并且在此基础上,结合渗流计算,利用有限元模型对水泵在注水回收过程中可产生的最大舱内压强进行了预测,对比最大舱内压强与基础拆除所需的启动舱内压强即可判断此水泵能否用于注水加压拆除.本文所得结论可为海上风电桩基础的退役处理提供参考,有助于保障风场海床资源的可持续利用,具有一定的工程价值.
In recent years,the global offshore wind energy has kept a rapid growth.As the earliest foundation type used in offshore wind power generation,monopile foundations dominate in offshore wind farms worldwide.Since the existing turbines typically last around 20 years,a large number of them are expected to be decommissioned in the next decade,which illustrates the increasing importance of recovering offshore pile foundations.To address the prob-lem of decommissioning and demolishing offshore pile foundations,a water injection demolition method was studied in this paper based on physical model experiments.Experimental results indicate that when using the proposed water injection demolition method,larger-diameter pile foundations required lower pressure,and the initial tilt angle had a limited impact on the required pressure,although a large angle may increase the risk of toppling.During the demolishing process,the chamber pressure drop due to the unit displacement of the pile foundation remained consistent,which was independent of the influences of foundation diameter,mud depth and tilt angle.Based on the combination of experimental data,soil mechanics and the hydraulic theory,a theoretical model for the whole demolition process was established,which can be used to predict the initial chamber pressure and chamber pressure-displacement curves under conditions of different pile diameters and different mud depths.Moreover,with the incorporation of seepage calculations and a finite element model,the maximum chamber pressure generated by a water pump during the water injection demolition process was predicted,so that whether the water pump was proper for injecting water can be determined by a comparison between the predicted maximum chamber pressure and the required pressure for founda-tion demolition.The findings in this paper provide a reference for decommissioning offshore wind power pile founda-tions,which contributes to the sustainable utilization of seabed resources in wind farms and is of engineering signifi-cance.
作者
张浦阳
信连硕
丁红岩
乐丛欢
Zhang Puyang;Xin Lianshuo;Ding Hongyan;Le Conghuan(School of Civil Engineering,Tianjin University,Tianjin 300350,China;State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation,Tianjin University,Tianjin 300350,China)
出处
《天津大学学报（自然科学与工程技术版）》
EI
CAS
CSCD
北大核心
2024年第4期437-444,共8页
Journal of Tianjin University：Science and Technology
基金
国家自然科学基金资助项目(52171274).
关键词
海上风电
桩基础
拆除
注水加压
模型实验
offshore wind power
pile foundation
demolition
water injection
model experiment
