关于《材料力学》中两个重要问题的商榷

On the Discussion of Important Problems in the Strength of Materials

本文对用最简单的方法推导基本公式和“设正法”用于材料力学中两个重要问题提出商榷。从平面假设,变形几何关系,物理及静力平衡条件出发,根据变形的直观性,引进比例常数C,使推导基本的应力公式得到优化处理;采用“设正法”的思想,将它应用于材力中写内力方程,作内力图,既简便、又准确,使材力中很关键的一部分内容——危险面的确定,得到优化处理。

Two important problems i.e.using the simplest method to de- rive basic formula and using the plus assumption method in the strength of materials were discussed in this paper.Beginning with plane section assum- ptions,physics and statics balancing conditions,and according to the audio- visual characters of deformation,a proportional constant C was introduced to optimize the processing in deriving basic stress formula.Adopting the plus assumption method in the strength of materials would make the internal force equation set and internal force figure drawing more simple and more exact,and make the definition of the dangerous seetion—the key part cour- se in the strength of materails—be processed optimally.