基于极限平衡法的箱筒型基础防波堤稳定性分析

Stability analysis of bucket foundation breakwaters based on limit equilibrium method

箱筒型基础防波堤是一种适用于软土地基和深水波浪条件的新型港口与海岸工程结构,依靠沉入地基中的筒型基础维持结构稳定。根据箱筒型基础防波堤极限状态下的结构运动模式,考虑箱筒型基础防波堤的三维空间几何特性、受力特点、极限状态转动点的位置等因素,建立了箱筒型基础防波堤稳定性计算的极限平衡法,通过与有限元结果对比,相互验证了正确性,与有限元法相比,极限平衡法计算速度快,效率高,更方便工程应用。结合天津港防波堤延伸工程,对箱筒型基础防波堤的稳定性进行了分析。结果表明,基础筒高8～10 m时,天津港延伸工程中的箱筒型基础防波堤的抗滑、抗倾和竖向承载力均具有较高的安全度。

The bucket foundation breakwater is a new type of port and coastal engineering structure suitable for soft foundations and deep water waves, the stability of which is sustained by the bucket foundation penetrated in soils. According to the motion mode of the bucket foundation breakwater in the limit state, a limit equilibrium method is established in consideration of its three-dimensional geometry, force characteristics and rotation point position. Compared with the finite element method, the limit equilibrium method is consistent in the calculated results. But the limit equilibrium method has faster calculation speed and higher efficiency. So it is more convenient in engineering application. According to the project of extending breakwaters in Tianjin Port, the stability of the bucket foundation breakwater is analyzed. The results show that when the height of the bucket is 8 to 10 m, the anti-sliding, anti-overturning and vertical bearing capacities of the bucket foundation breakwater in the project all have high degree of safety.