23.3 : 主应力：解决问题

Two planes that are at right angles carry shearing stress along with tensile and compressive stresses. With known stress values, determine the principal planes, maximum shearing stress, and principal stresses.

The principal planes are determined using the relation where the principal plane equals the ratio of twice the shearing stress to the difference between tensile and compressive stresses.

Substitute the known values of shearing stress, normal stress, and compressive stress into the equation to calculate the principal plane values.

The average normal stress is then determined by calculating the average value of tensile and compressive normal stresses.

Next, calculate the maximum shearing stress by substituting the values of normal and shearing stresses into the equation.

Calculate the major principal stress by adding the average normal stress value to the maximum shearing stress.

The difference between the average normal stress value and the maximum shearing stress is the minimum principal stress.