Principal Stresses

Principal stresses are the maximum and minimum levels of internal force per unit area that a material experiences when subjected to external loads. Imagine a block of material being pushed or pulled from different directions; these stresses vary inside the material. Principal stresses are the specific orientations where the shear (sideways) stresses are zero, leaving only normal (direct) stresses. They help engineers understand how a structure will handle forces without breaking, allowing for safer and more efficient designs. Essentially, they identify the most critical stress points within the material under complex loading conditions.