Combination of Material Models
It is possible to combine many of the effects in an additive manner. The models based on elasticity all have the same structure where
1
An elastic strain is computed by removing all inelastic strains (for example, plastic or thermal strains) from the total strain.
2
An “elastic stress” is computed from the elastic strains.
3
Any additional stresses (for example viscous stresses, or initial stresses) are added to form the total stress.
This concept will give you a great freedom in combining effects. Some such useful combinations are
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Plasticity and thermal expansion
•
Plasticity and creep
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Thermal expansion and hygroscopic swelling
•
Viscoelasticity and creep