本文视斜放四角锥网架结构为一交叉梁系,其基本微分方程式按有限差分法求解,得到了相应的差分方程式及各种边界条件下的开拓值。概念明确,推演简捷。在周边简支条件下,本文所得结果与日本学者提出假想弯矩法相同;并指出假想弯矩法实质上是一种差分解法。对于具有自由边界的情况,本文也推得了相应的方程式。 In this paper, the oblique quadrangular pyramid grid structure is a cross-beam system. The basic differential equations are solved by the finite difference method. The corresponding difference equations and the pioneering values ​​under various boundary conditions are obtained. The concept is clear and simple. Under the condition of simple surrounding support, the results obtained in this paper are the same as those of the hypothetical bending moment method proposed by Japanese scholars. It is pointed out that the virtual bending moment method is essentially a differential decomposition method. For the case of free boundaries, this paper also derives the corresponding equations.