Mohr’s circle is a graphical representation of a general state of stress at a point.
With the help of Mohr’s Circle, we can evaluate principal stress, maximum shear stresses, also normal and tangential stress at any plane.
Many questions come in exam related to principal stress and with help of Mohr’s circle they are solved in seconds.
Let’s see the rules and sign conventions to follow to make Mohr Circle:
When drawing Mohr’s Circle, always remember
- X-Axis shows Direct Stress
- Y-Axis shows Shear Stress
Tensile stress always considered positive and will be always plotted right side to origin O.
Clockwise Shear considered Positive.
If θ is in anticlockwise direction then θ will be taken positive & radius vector will be above axis .
Compressive stress always considered negative and will always be plotted on left side of origin O.
Anti-Clockwise Shear is considered Negative.
If θ is in clockwise direction then θ will be taken negative & radius vector will be below axis .