文中结合在固体火箭发动机立式推力台架设计中需要给出一定频率范围的工程实际问题,首先将推力台架结构简化成典型多层空间刚架模型,然后探讨了多层空间刚架结构的一般振动计算方法,最后在推力台架结构模型进行合理简化的基础上,依据角变形法从能量角度给出了推力台架关于固有频率的工程解析计算,并进一步确定了结构可调的立式推力台架固有频率的变化范围,为类似多层空间刚架结构的工程振动设计与计算提供了有价值的参考。

The free vibration equation for the horizontal elastic support multilayer structures is established by the flexibility method for the multiple frame of a solid rocket stand. The additional inertia force of the multilayer foot mass is taken into account. The natural frequency is shown to be a small varying scope. The horizontal elastic support affects the vibration modes. Especially for higher modes, the horizontal elastic support multilayer vibrates completely in accordance with the circular beam.