水电站地面厂房发电机层楼板高程以上存在排架结构。为研究厂房上部排架简化模拟方法对厂房振动特性仿真结果的影响,运用ANSYS软件建立了3种有限元模型,分析了厂房的自振特性和机组振动荷载作用下的响应特点。研究表明:在开展水电站地面厂房的自振特性分析时,当主要期望了解楼板、立柱等结构的自振特性时,为简化计算,可以将发电机层楼板高程以上的排架结构采用质量单元来模拟,或者直接省略掉,均不会对结果造成较大影响;在机组振动荷载作用下,排架结构的振幅和动应力并不是厂房结构中最大的部分,除非要了解排架结构的振幅和动应力,否则均可以将排架结构进行简化处理,该简化处理对厂房结构振幅和动应力的影响程度不大。

Bent is widely used above generator floor elevation in ground hydropower house. In order to study the influence of simulation method of bent on the simulation result of vibration characteristics of power house, we built three finite element models in ANSYS to simulate the natural vibration characteristics and dynamic responses of generator unit under vibration loads. The study shows if the focus was on the free vibration characteristics of floors and columns, the bent could be simulated by mass elements or be ignored because the vibration amplitude and dynamic stress of bent are not the most intensive. In conclusion, unless the vibration amplitude and dynamic stress of bent are main research object, the bent could be simplified, which would exert no impact on the dynamic response of powerhouse structure.