An improved dynamic Monte Carlo damage microscopic numerical constitutive model incorporating thermo-mechanical coupling for unidirectional GRP under tensile impact

The phenomenon of thermo-mechanical coupling exists in the adiabatic process of unidirectional glass/epoxy composite (GRP) under tensile impact loading. In the present paper, the frictional work generated by matrix breakage or interfacial debonding is taken into account in order to improve the iteration calculation of thermo-mechanical coupling. An improved dynamic Monte Carlo damage microscopic numerical constitutive model incorporating thermo-mechanical coupling is set up. By means of this improved model, the deformation, damage and failure process of unidirectional GRP under tensile impact is simulated numerically. The apparent tensile stress/strain relationships of GRP at different high strain rates are predicted. The numerical results are in good agreement with the experimental data, which proves that the improved model is reasonable and effective. It also reveals that the dominant physical mechanisms of the non-linearity of the stress/strain curve for GRP are the temperature and strain-rate dependence of the mechanical properties of glass fiber and the thermo-mechanical coupling. The frictional work must be considered during the iteration calculation of the thermo-mechanical coupling and its contribution to the transient temperature rise of GRP under tensile impact cannot be neglected.