Viscoelasticity

Summary

Viscoelasticity is the behaviour of materials that respond to load partly like an elastic solid and partly like a viscous fluid. Their stress depends not only on the present strain but on the whole past history of strain, so they are materials with memory. They show creep under constant stress, stress relaxation under constant strain, and energy loss in cyclic loading. Polymers, biological tissue, asphalt and many soils are viscoelastic, and in the linear theory the response is fixed by one function, the relaxation modulus.