自由表面波和水体压缩性对深水桥墩地震动水压力的影响

Influence of Free Surface Wave and Water Compressibility on Earthquake Induced Hydrodynamic Pressure of Bridge Pier in Deep Water

地震时深水桥墩会受到动水压力作用,深入分析深水桥墩地震动水压力具有重要意义.基于辐射波浪理论建立深水桥墩地震动水压力计算公式,分析自由表面波和水体压缩性对动水压力的影响.研究表明:自由表面波仅在荷载激励频率较低时影响水面附近的动水压力;水体压缩性仅在荷载激励频率较高时影响动水压力.因此,在长大桥梁地震灾变过程模拟中可忽略自由表面波和水体压缩性对深水桥墩地震动水压力的影响.

Hydrodynamic pressure is applied to bridge pier in deep water under earthquake excitation.It is of great significance to analyze earthquake induced hydrodynamic pressure of bridge pier in deep water.Earthquake-induced hydrodynamic pressure formulary was established using radiation wave theory.The influence of free surface wave and water compressibility on hydrodynamic pressure of bridge pier was studied.The results indicate that free surface wave will only influence hydrodynamic pressure in the vicinity of water surface under low-frequency load excitation.Water compressibility only has an effect on hydrodynamic pressure under high-frequency load excitation.In conclusion,the influence of free surface wave and water compressibility on earthquake induced hydrodynamic pressure can be ignored in earthquake hazard simulation of long and huge bridge.