槽内水深对渡槽-水体耦合结构抗震性能的影响

Effects of Water Depth on Seismic Performance of the Aqueduct-water Coupling Structure

采用有限元数值计算方法,研究槽内水深的变化对渡槽-水体耦合结构抗震性能的影响。数值结果表明,水体的存在使得渡槽结构的振动频率降低,在地震作用下,"U"形渡槽中水体的晃动幅度十分显著,从而改变了槽身地震反应性态。槽内水体对渡槽结构的影响程度与输入地震波的谱特性有很大关系,当输入地震波的主频范围覆盖渡槽结构基频,且槽内水体的振动频率与渡槽结构基频相近时,槽内水体对渡槽结构可以起到类似调谐液体阻压器(TLD)的减震效应,并对槽内水体减震效应的条件进行了判别。

The effects of water depths in aqueduct on the seismic performance of aqueduct-water coupling structure are studied by using finite element method. The resuhs show that： （a） the vibration frequency of the structure is reduced due to the existence of water and the response wave of aqueduct body is changed as very significant sloshing amplitude of the water in U-shape aqueduct; （b） the effects has great relationship with the spectrum dynamic properties of the input earthquake wave, and water body in aqueduct can play TLD damping when the frequency scale of earthquake wave covers the structure fundamental frequency and the water vibration frequency is closed to the structure fundamental frequency. The approximate criterion is also put forward to adjudge.