Strength of Materials

2.5 MOHR’S CIRCLE

If a plot is made with normal stresses used as abscissas and shearing stresses as ordinates, and if points are plotted to represent stress coordinates for all possible values of θ, it is found that the locus of these points is a circle, as shown in Figure 2.11.

 

 

Fig. 2.11 Mohr’s stress circle.

 

This circle has its centre on the x-axis, and cuts it at abscissas of σ₂ and σ₁. Any point on the circle represents the coordinates of stress on some plane. Thus, point C in Figure 2.11(a) is for the θ value as given in Figure 2.11(b). This circle is the graphical representation of the state of stress in a lucid form which is known ...