主应力与主平面对应关系的两种直观判断法

A Method of TwO Intuitional Judgement on the Relation Between the Main Stress and the Main Plane

本文根据平面应力状态任意斜截面正应力对α角的变化率确定σ_α的增减性,再由σ_y、σ_x、和τ_x 的数量关系,找到较大主应力作用的截面方位,从而可以根据所得的结论直观判断平面应力状态的主应力与主平面的对应关系。

This paper suggests that the relation between the main stress and the main plane can be judged from the following result first determine the increase or decrease in σ_x from the changing ratio of the arbitrary inclined plane to the angle α under the plane stress,the find out the section attitude acted by the larger main stress from the value of σ_x,σ_y and τ_x.