After reducing the strain gage rosette data, the following normal and shear strains have been determined:

εx   =   +770 με

εy   =  -350 με

γxy   =   +1,940 μrad


For the normal stress in the x direction:

σx=E(1-ν2)(εx+νεy)=70,000MPa(1-0.332)[0.000770+(0.33)(-0.000350)]

=51.41MPa

Note: The strain values must be converted from με to dimensionless values (i.e., mm/mm) before performing the calculation.

Principal stresses from rosette data