I am modeling FEA of compression of Glass at high temperature assuming viscoelastic material model. The viscoelastic relaxation is considered only in shear and the bulk is assumed constant and incompressible (constant vol.). The shear relaxation times are of the order of milliseconds.
Now at the end of the analysis, I have stresses arising from the bulk or volume part. Ideally, the stresses would be 0 because of very quick relaxation. I am not sure how to interpret these stresses due to bulk. What do they mean? Do these stresses mean springback can occur once the load is removed?
Any suggestion is appreciated!