Pavluyk Y. Nonlinear creep and relaxation of nonlinearly-viscoelastic materials under different nonstationary uniaxial loading regimes.

The Thesis is devoted to the derivation and experimental justification of a nonlinear one-dimensional viscoelastic model of hereditary type and to the solution of the problems prediction of creep strains and stress relaxation of nonlinearly-viscoelastic materials under different uniaxial nonstationary loading regimes. A nonlinear one-dimensional viscoelastic model of hereditary type with the time independent nonlinearity is developed. System of resolving equations of nonlinear creep under different nonstationary uniaxial loading regimes is formulated. The calculation results of creep strains and stress relaxation of some nonlinear-viscoelastic composites and their components under additional loading, partial and full unloading, alternation of loading and unloading as well as cyclic loading have been approved experimentally.