Internal friction analysis for the viscoelastic constitutive models

Abstract

In this paper, the internal friction for the viscoelastic materials such as asphalt is analyzed theoretically. The variation of the strain energy and internal friction per period when an alternating stress is applied to the viscoelastic material is discussed which shows that the storage and release of the strain energy are alternately carried out. The internal friction per period is related to the loss modulus. However, it is independent of the energy storage modulus. In addition, the energy storage modulus, loss modulus, tangent of loss angle and internal friction for four viscoelastic constitutive models, i.e., Maxwell model, Kelvin model, Lessersichi model and Jeffreys model, are calculated from which we know that they are all the functions of frequency. When the frequency is zero, the internal friction for the Kelvin model and Jeffreys model are zero, while the Maxwell model and Lessersichi model are infinity.