船撞作用下斜桩基础动力响应研究

东海大桥100MW海上风电示范项目中风机采用斜桩基础,必须考虑船撞作用。本文利用有限元方法,研究了斜桩基础在船撞作用下的动力响应。模拟不同工况,研究船舶吨位、船舶速度、倾斜角、桩径、桩周土体等因素对桩基的动力响应的影响。研究表明:船舶吨位和船舶速度对斜桩的动力学响应影响最大;桩的倾斜角会影响最大桩项位移,最优倾斜角约为10°;在既定的土质条件下,桩径增大到某一值后,桩基动力响应基本不变;土体较软时,桩身的最大应力较小,但最大桩顶位移较大。因此,进行斜桩设计时,必须在理论分析的基础上,选取合适的倾斜角与桩径。本文研究结果对斜桩基础在考虑船撞作用下的设计和施工有一定参考价值。

Study on the Dynamic Response of Batter Piles under Ship Impact

The batter pile was adopted in project of offshore wind farms of DongHai Bridge in Shanghai. The dy- namic response of batter pile under ship impact should be studied, while finite element method was employed. Several factors including ship weight, ship velocity, angle of slope, pile diameter and characterization of soil around the pile were taken into account, and different working conditions were simulated. Some conclasions were explored ： the dynamic responze of the batter pile was affected by ship weight and ship velocity mostly ; the maximal horizontal displacement of the pile top was affected by angle of slope, and the optimal angel was about 10~; influence of the diameter of pile un- der given soil condition would keep unchanged, when the diameter of pile climbed to a certain value ; in the softer soil, yon-raise stress of pile body was small and the maximal horizontal displacement of pile top was large. So the angle of slope and the diameter of batter piles should be chosen appropriately during design on the base of theory analysis. Re- sult of the study in the paper could be reterred during the design and construction for batter pile under ship impact.