冲刷深度对海上风电复合筒型基础结构安全性的影响分析

Impact Analysis of Scour Depth on the Security of Composite Bucket Foundation of Offshore Wind Turbines

结合某海上风电工程,通过开展复合筒型基础的数值模拟,研究了冲刷深度对复合筒型基础结构安全性的影响,包括对基础变形、极限抗倾覆承载力、结构应力和整机固有频率的影响。研究结果表明,随着冲刷深度的增加,基础变形和筒体结构应力增加,而极限抗倾覆承载力和整机结构固有频率降低。以筒径36 m、筒长10 m的复合筒型基础工程为例,当基础顶所受弯矩M=389×106 N·m、基础周围土体冲刷为4 m时,基础顶转角增加11.7%,基础极限抗倾覆承载力降低23.2%。此外,相比于基础变形、极限抗倾覆承载力,结构应力和整机结构固有频率受冲刷深度影响相对较小。

In combination with an offshore wind power project,the numerical simulation of composite bucket foundation is carried out,and the impact of scour depth on the security of composite bucket foundation is studied,including the impact on foundation deformation,ultimate anti-overturning capacity,structural stress and natural frequency of the whole structure.The results show that,with the increase of scour depth,the deformation of foundation and the stress of bucket increase,while the ultimate anti-overturning capacity of foundation and the natural frequency of the whole structure decrease.Taking the composite bucket foundation used in a project with a diameter of 36 m and a bucket length of 10 m as example,when the bending moment is 389×106 N·m on the top of the foundation and the soil erosion depth around the foundation is 4 m,the angle of foundation top increases by 11.7%,and the ultimate anti-overturning capacity of foundation decreases by 23.2%.In addition,compared to the deformation and the ultimate anti-overturning capacity of foundation,the structural stress and the natural frequency of the whole structure are less affected by scour depth.