Maximum shear stress theory states that failure will occur if maximum shear stress equal to or greater than maximum shear stress when perform failure test to uniaxial tension. The formula can be shown as follows:
| σ1 - σ2 | ≥ | σf |
| σ2 - σ3 | ≥ | σf |
| σ3 - σ1 | ≥ | σf |
Where:
σf = uniaxial tensile strength
σ1, σ2, σ3 = main stresses
Graphical representation of maximum shear stress theory is shown is Figure 1 below:
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| Figure 1: Graphic of Maximum Shear Stress Theory |