材料力学是研究杆件在外力作用下的变形、受力和破坏的规律，为合理设计杆件提供有关强度。刚度和稳定性分析的基础理论和方法。材料力学研究的对象主要是杆件，在不同形式的外力作用下，杆件的基本变形有轴向拉伸（压缩）、扭转和弯曲三种形式。梁的弯曲变形是杆件基本变形的 Material mechanics is to study the law of deformation, force and destruction under the action of external force, and provide the strength for the rational design of the rod. The basic theory and method of stiffness and stability analysis. Material mechanics research is the main object of the rod, under the action of different forms of external forces, the basic deformation of the rod axial stretching (compression), twisting and bending of three forms. Beam bending deformation is the basic deformation of the bar