|FINITE ANGULAR ROTATION
The rotation principal strains during deformation may vary and will describe fully how the aterial may behave during deformation. The diagram is from Ramsay and Huber 1983. The top shows that the angular rotation is zero, a condition of no rotation of principal strains. This is therefore a case of pure shear. But the principal strain ratio by an extension or stretch of 0.1. The second diagram shows that the principal strains rotate at each stage through 4 degrees, the total rotation being 40 degrees. This change also brings about an attendant increase in finite strain ratio. The rotation then is parallel to the asymptotes. The deformation is non-coaxial complex.