某大桥桥墩防撞设计研究与应用

Research and Application on Anti-collision Design of Bridge Piers of a Certain Bridge

摘要:

为有效避免船桥碰撞以及降低撞击力对桥梁结构的影响，基于某大桥桥梁通航情况和桥墩形式的具体分析，提出了浮动式柔性钢套箱、浮动式钢覆复合材料结构，同时结合主动预警系统的复合桥墩防撞方案，并通过建立船桥碰撞有限元模型验证设计方案的可行性。结果表明：采用浮动式柔性钢套箱防撞方案的R4号桥墩其横桥向正撞船撞力由18.89 MN降至9.39 MN，顺桥向侧撞船撞力由9.45 MN降至4.54 MN，降幅均超过50%，下降后的船撞力未超过桥墩相应的横桥向抗力9.9 MN和顺桥向抗力5.1 MN，防撞设施效果显著；采用浮动式钢覆复合材料结构防撞方案的R3、R5号桥墩其船撞力经计算也分别下降超35%、37%，均未超过桥墩实际抗力；桥墩防撞设施安装工艺成熟、施工方便，配合桥梁防撞主动预警系统，显著提升了桥墩与航道的综合安全水平。

Abstract:

To effectively avoid the ship-bridge collisions and reduce the impact force on the bridge structure, based on the specific analysis of the navigation conditions and the pier form of a certain bridge, a composite bridge pier anti-collision scheme is proposed, featuring floating flexible steel casing box and floating steel cladding composite material structure, combined with an active early warning system. The feasibility of the design scheme is verified by establishing a finite element model for ship-bridge collision simulation. The results show that for Pier R4 equipped with the floating flexible steel casing, the transverse head-on collision force is reduced from 18.89 MN to 9.39 MN, and the longitudinal side collision force is reduced from 9.45 MN to 4.54 MN, both exceeding a 50% reduction. The post-reduction collision forces are below the corresponding transverse resistance of 9.9 MN and longitudinal resistance of 5.1 MN for the pier, demonstrating significant effectiveness of the anti-collision facilities. For Piers R3 and R5 equipped with the floating steel cladding composite material structure, the calculated collision forces are also reduced by over 35% and over 37%, respectively, and remain below the actual resistance of the piers. The installation process for the pier anti-collision facilities is mature and convenient for construction. Combined with the active collision warning system of bridge, the overall safety level of the piers and the waterway is significantly enhanced.