复杂环境荷载下斜拉桥单塔结构随机响应与破坏机理分析

The offshore bridges will suffer different degrees of damage under the disturbance or action of wave and earthquake loads. Therefore, both the quantification of wave and earthquake loads and the establishment of reasonalble numerical simulation analysis method considering fluid-solid interaction for cross-sea bridge are under urgent need. From the perspective of theoritical and engineering practice, various research methods including model test, numerical analysis and simulation technology are utilized in this topic to discuss and study the response of bridge under the excitation of earthquake and wave loads with different perspective and weighted emphasis. Comprehensive model test in water pool for the single tower structure of cable-stayed bridge is conducted, and elaborating and reasonable finite element analysis model of the single tower structure of cross-sea cable-stayed bridge considering fluid-solid interaction mechanism is established. Numerical inversion for the extreme stochastic wave load acting on group-pile structure is carried out by means of combining both theoretical analysis and model test. The calculation of response power spectrum, especially the strain and stress spectrum for fluid coupled structure under the combining excitation of strong earthquake and extreme sea wave is achieved. The failure mechanism of cross-sea bridge structure under the action of harsh environmental loads is studied intensively, which offers the profound theoretical basis and effective analysis methods for the design and evaluation of bridge under wave and earthquake actions.

位于近海桥梁在波浪与地震荷载的干扰或作用下将遭到不同程度的破坏，因此，急需搞清波浪与地震荷载,制定规范合理的跨海桥梁流固耦合数值仿真分析方法。本课题从理论和工程实际的角度出发，利用模型实验、数值分析和模拟技术等各种研究途径和手段，从不同的角度分别有所侧重地对斜拉桥单塔结构在地震和波浪荷载作用下响应问题进行探讨和研究。进行斜拉桥主塔综合水池试验，建立精细合理的跨海斜拉桥主塔—水结构流固耦合有限元分析模型；采用理论分析与试验相结合的手段对作用于群桩结构的极端波浪随机载荷进行数值反演；实现流固耦合结构在强震和极端海浪共同作用下响应功率谱、特别是应变谱和应力谱的计算。深入研究复杂环境载荷作用下跨海桥梁结构破坏机理，为桥梁的抗波浪和地震设计和评价提供坚实的理论基础和有效的分析手段。

位于近海桥梁在波浪与地震荷载的干扰或作用下将遭到不同程度的破坏，因此，急需搞清波浪与地震荷载,制定规范合理的跨海桥梁流固耦合数值仿真分析方法。本课题从理论和工程实际的角度出发，利用模型实验、数值分析和模拟技术等各种研究途径和手段，从不同的角度分别有所侧重地对桥梁结构在地震和波浪荷载作用下响应问题进行探讨和研究。进行斜拉桥主塔综合水池试验，建立精细合理的跨海斜拉桥主塔—水结构流固耦合有限元分析模型；采用理论分析与试验相结合的手段对作用于群桩结构的极端波浪随机载荷进行数值反演；深入研究了复杂环境载荷作用下跨海桥梁结构破坏机理，为桥梁的抗波浪和地震设计和评价提供坚实的理论基础和有效的分析手段。