螺栓联接结构模态频率有限元计算的简化方法

螺栓联接是机械结构中广泛采用的联接形式，而螺栓预紧力是影响螺栓连接结构的模态频率值的主要因素。通过对经典螺栓理论进行研究，提出了一种模拟螺栓预紧力的简化方法，并使用有限元软件对简化前后的螺栓联接结构进行了模态分析。研究表明，该方法模拟螺栓联接预紧力所得的模态频率的结果与模态试验结果吻合较好，并且与简化前螺栓联接结构的有限元计算结果有很好的一致性，并且计算速度有很大提高。表明所提出的方法可行，能满足工程要求，具有一定的应用价值。

Simplified calculation of modal frequency of bolted structure by FEM

Bolted connection structure is widely used in engineering, and bolted pretension is the main factor that decides the value of modal frequency. Based on the classic theory of bolt, this paper proposes a simpli- fied method to simulate bolted pretension and uses FEM to carry out a modal analysis of the fact structure and the simplified structure. The modal results obtained from this method which simulate bolted preload not only agree well with the modal experiment results, but also has a good coherence with that of actual bolted structure. In addition, the calculation speed is greatly enhanced. These demonstrate the validity of the meth- od used, and the method has a value in engineering.