复杂变截面梁的轴向自由振动分析的近似方法

介绍了带有附加影响的变截面梁轴向自由振动问题的求解方法－模态摄动法，这一方法在由等截面均匀梁低阶主模态函数组成的模态子空间中，将复杂梁的变系数微分方程的求解化为线性代数方程组的求解，从而简化了计算过程，通过与其它方法的比较，说明了本文方法的优越性。

Approach for Longitudinal Free Vibration of Complicated Beams with Variable Cross Sections

A simplified method,which may be called modal perturbation method,for solving the longitudinal free vibration of complicated beams with variable cross sections is introduced in the paper,In the method,the lower analytical longitudinal modal functions of the uniform beam are used to form an approximate solution subspace,Then the governing differential equation with variable coefficients for longitudinal modal analysis is given instead of a set of algebraic equations established in the subspace and thus,the computational procedure is simplified effectively.The numerical results show that the method has higher calculating precision.