Determination of the Creep Parameters of Linear Viscoelastic Materials

Abstract EN

Creep process of linear viscoelastic materials is described by the integral equation of Boltzmann-Volterra in which creep kernel is approximated by Rabotnov’s fractional exponential function.

The creep equation contains four unknown parameters: α , singularity parameter; β , fading parameter; λ , rheological parameter; and ε 0 , conditionally instantaneous strain.

Two-stage determination method of creep parameters is offered.

At the first stage, taking into account weak singularity properties of Abel’s function at the initial moment of loading, parameters ε 0 and α are determined.

At the second stage, using already known parameters ε 0 and α , parameters β and λ are determined.

Analytical expressions for calculating these parameters are obtained.

An accuracy evaluation of the offered method with using experimentally determined creep strains of material Nylon 6 and asphalt concrete showed its high accuracy.