针对矩形截面悬臂梁受任意五次多项式分布载荷作用的情况,采用逆解法,构造一个既满足双调和方程,又满足边界条件的应力函数,并且运用此应力函数求解出了该情况下的各应力分量.此外,将该理论应用于一个工程实例中,理论计算与实验结果比较吻合.克服了矩形截面悬臂梁受五次多项式分布载荷作用时选取应力函数的盲目性,为选取矩形截面悬臂梁在更复杂载荷下的应力函数奠定了基础. Aiming at the problem that the rectangular cross-section cantilever beam is subjected to any quintic polynomial distributed load function, an inverse solution method is used to construct a stress function which satisfies the dual harmonic equation and satisfies the boundary conditions. The stress function is used to solve the stress in this case In addition, the theory is applied to an engineering example, the theoretical calculation is in good agreement with the experimental results, which overcomes the blindness of selecting the stress function when the rectangle-shaped cantilever beams are subjected to the quintic polynomial distributed load. The stress function under more complex loads lays the foundation.