V-H-T荷载空间内海上风机桶形基础破坏包络面特性分析

Failure envelopes of bucket foundation for offshore wind turbines in V-H-T loading space

与海上采油平台的基础不同,用于海上风力发电机的吸力式桶形基础不但承受着上部结构所传来的竖向荷载V、风浪等引起的水平荷载H,还承受着叶片等旋转机构传来的扭矩T。在swipe加载方法和固定位移比加载方法的基础上,建议了荷载-位移联合搜索方法。采用该方法对于桶形基础在V-H、V-T、H-T荷载平面内以及V-H-T非共面复合加载条件下的稳定性进行了三维有限元数值分析,得到了V-H-T荷载空间内的破坏包络面。由此可根据实际的受力状态与该破坏包络面之间的相对关系,评价实际荷载状态下海上风力发电机桶形基础的稳定性。

The suction bucket foundation for offshore wind turbines is subjected to not only vertical loading caused by structural weight and horizontal loading and moment due to wind- or wave-induced loading, but also torque from rotor blades, as opposed to the foundation for offshore oil production platforms. Based on swipe test loading method and fixed displacement ratio loading method, a combined load-displacement searching method is proposed. Utilizing the proposed method, three dimensional finite element numerical analyses are conducted to explore the failure mechanisms of bucket foundation in different loading planes, such as V-H, V-T, H-T and in V-H-T loading space under out-of- plane combined lading. The failure envelopes in different loading spaces are obtained. According to the relationship between the actual combined loading and the computed failure envelopes, the stability of bucket foundation could be evaluated.