弯扭组合作用梁的一种新型实验方案

A Novel Experimental Scheme of Beams under Bending and Torsion

基于梁的弯曲、轴的扭转和应力应变分析等理论,设计了一个创新型弯扭组合实验方案。利用梁的弯曲变形理论计算横向外载荷引起的横截面上的正应力和切应力,利用轴的扭转理论计算外力偶矩引起的横截面上的周向切应力,结合切应力互等定理和广义胡克定律计算出梁外表面上任意点任意方向的应变,并与实验测试值进行比较。教学过程及教学效果表明,该实验方案能够使学生增强对基础理论的理解,提高对知识的运用能力。

Based on the theories of analysis on beams subjected to the combined action of bending and torsion,stress and strain,an innovative experiment of beams under bending and torsion was designed. Beam bending located on the cross-section deformation theory is employed to calculate the normal stress and shear stress caused by the lateral force. The shaft torsion theory is adopted to calculate the circular shear stress on the cross section caused by the external moment of couple. Then,the shear stress reciprocal theorem and the generalized Hooke＇s Law are used to calculate the strain appearance of arbitrary direction of an arbitrary point on the surface of the beam,and are compared with the experimental values. Teaching practice shows that this experiment scheme can improve the understanding of basic theories of students and their ability to use the theoretical knowledge.