桥墩柔性自浮式防撞装置基本结构尺度研究

Study on Basic Structural Scale of Flexible Self-Floating Anti-Collision Device for Bridge Piers

为对柔性自浮式防撞装置的结构尺度进行合理设计,提出了该类装置的桥墩抗撞方向截面总宽度最小保障尺度、中间保障尺度和完全保障尺度3种基本结构尺度的概念,并以此确定其合理取值范围。针对设防等级为3000吨级船舶的柔性自浮式防撞装置,采用放样统计的方法,按85%保证率确定不同截面高度防撞装置的最小保障尺度取值;基于机械能守恒原理及有限元法给出完全保障尺度的经验计算公式;结合完全保障尺度及最小保障尺度的取值,考虑桥墩维修量及桥梁安全,给出中间保障尺度的建议值。提出防撞装置的基本结构尺度不应小于最小保障尺度,宜优先满足完全保障尺度,如无条件实现完全保障尺度时,可采用中间保障尺度。

To determine the reasonable structural scale of the flexible self-floating anti-collision device,the concepts of three basic structural guarantee scales associated with the full width of the impact surfaces of the pier,namely the minimum guarantee scale,intermediate guarantee scale and complete guarantee scale,are proposed.The flexible self-floating anti-collision device must be capable of resisting impact forces of 3000-t ships,in this case,the minimum guarantee scales of the anti-collision devices for piers with different impact surface widths are calculated taking into account 85% guarantee rate.Following the principle of mechanical energy conservation and finite element calculation,the empirical formulas to calculate the complete guarantee scale are presented.Considering the complete guarantee scale and minimum guarantee scale,as well as the repair work of the piers and bridge safety,the intermediate guarantee scale is given.It is recommended that the basic structural guarantee scale of the anti-collision device be no less than the minimum guarantee scale,and must first fulfil the requirements of complete guarantee scale,while if impossible,implement the intermediate guarantee scale.