水-振动台相互作用竖向动力试验研究

Vertical dynamic tests on the interaction between water and shaking table

水下振动台在设计制造过程中,需要考虑水与振动台间的动力相互作用,其产生的动水附加质量对振动台台面尺寸、台面形状、作动器能力、振动台控制方法的确定有重要影响。鉴于现有流固耦合作用相关理论不能用于水-振动台相互作用,本文通过试验方法,研究动水附加质量随振动台激励幅值、激励频率、水深的变化规律。试验结果表明,动水附加质量在水深较小时随着激励幅值的增大而减小,水深较大时随着幅值的增大先减小后增大;动水附加质量随激励频率的增大而减小,随水深的增大先增大后减小。通过公式拟合,建立水-振动台相互作用产生的动水附加质量的经验公式,为水下振动台系统优化设计提供依据。

During the design of underwater shaking table system,the interaction between water and shaking table needs to be considered because the added mass derived from it has great influence on the design of the dimension and shape of the table,the capacity of actuators,and the control algorithm of the shaking table.As the existing theory of fluid-structure interaction cannot be used to calculate the interaction between water and shaking table,this study chooses to investigate the changing rule of added mass with the excitation amplitude,the excitation frequency,and the water depth by dynamic tests.The results show that the added mass decreases with the increase of the amplitude of the excitation at low water depth,while it first decreases and then increases with the increase of the amplitude of the excitation at high water depth.The added mass decreases with the increase of the frequency of the excitation,and first increases and then decreases with the increase of the water depth.An empirical formula is proposed to calculate the added mass caused by the interaction between water and shaking table,which can guide the design of underwater shaking table system.