以一典型深水矩形空心高墩为例,采用完全数值法,基于势流理论建立了桥墩-水流固耦合数值分析模型,分析了墩身仅外有水、仅内有水,以及内、外均有水等3种情况下桥墩振动特性的变化规律.结果表明,墩-水耦合作用使得桥墩各阶振型周期有所增大,且墩身内、外均有水时增幅最大;当水深小于墩高一半时,桥墩低阶振型周期变化很小,但高阶振型周期变化较大;上部结构质量虽然会减弱流固耦合作用对桥墩低阶振型的影响,但会增大对桥墩高阶振型的影响.由于高阶振型对高墩底部剪力响应贡献较大,因此,水深不大时应当重视桥墩高阶振型周期的变化.%In this paper, a typical deep-water rectangular hollow high pier is taken as an example and the full numerical method is used to build the numerical models of pier-water interaction system based on the potential flow theory.The vibration characteristics of the deep-water pier are investigated for three scenarios including only with water outside the hollow pier, only with water inside the hollow pier, and with water both inside and outside the hollow pier.The research results indicate that the vibration periods of the pier increase due to the effect of pier-water interaction, with the maximum increase corresponding to the case of water both inside and outside the hollow pier.As the water lever is smaller than half of the pier height, the periods of low-order mode vibration of the pier change slightly, while the periods of high-order mode vibration change significantly.Although the mass of superstructure could mitigate the effect of fluid-structure interaction on the low-order modes of vibration of the pier, it would cause large effects on the high-order modes of vibration of the pier since the high-order modes of vibration contribute more significantly to the bottom shear of the pier, Therefore, great attention should be paid to the effect of pier-water coupling on the high-order modes of vibration of the pier when the water depth is not large enough.
展开▼
