材料力学中内力教学思考

材料力学中内力是一个非常重要的概念,分析和计算内力是研究构件变形的基础。截面法是计算内力最基本的方法。由于计算过程中涉及到内力正负号的规定与理论力学上外力正负号的规定不一致,导致学生在利用截面法计算内力时经常出错。文章在分析截面法计算内力基础上,提出求和法计算内力方法,经案例计算验证,可有效避免材料力学上内力正负号和理论力学上外力正负号的问题,为材料力学中内力计算教学提供参考。

The internal force is a very important concept in the mechanics of materials.The analysis and calculation of internal force is the basis of studying the deformation of components.Section method is the most basic method to calculate internal force.Due to the inconsistency between the internal force sign and the external force sign in theoretical mechanics,students often make mistakes when using the section method to calculate the internal force.Based on the analysis of internal force calculation by section method,this paper puts forward the method of internal force calculation by summation method,which can effectively avoid the problems of internal force sign in material mechanics and external force sign in theoretical mechanics,and provide reference for the teaching of internal force calculation in material mechanics.