在水电站厂房动力特性分析中,过去均不考虑机架的支撑和传力作用,更未考虑与机组的耦联作用。本文针对机组径向动荷载的作用方向不断改变,造成厂房、机墩等支撑结构的受力方式不断变化的特征,通过建立机组与厂房耦联振动模型,探讨了机组径向动荷载不同传递方式及其幅值是否随大轴摆度变化而变化对水电站厂房动力反应的影响规律,考虑导轴承油膜和机架支臂刚度变化的特点,提出了油膜和机架支臂刚度的合理模拟方法,为厂房结构动力反应计算提供了更为精确的分析方法。
In the analysis of structure dynamics of a hydropower house, the support and force transmission of the brackets as well as the coupling with the generator set are usually neglected. When the dynamic loads are considered, however, their direction change with time causes the changes in the forces on the hydropower house and its piers. In this paper, a dynamic response model of the power house and piers is constructed to simulate the coupling between the generators and the house structures and to study the influence of time variations of amplitude and transmission of the dynamic loads. Simulations of the oil-film and the bracket arm stiffness are also considered in the model. The proposed model and method can improve the accuracy of the dynamic response calculations of hydropower house structures.