TY - JOUR
T1 - A numerical homogenization scheme used for derivation of a homogenized viscoelastic-viscoplastic model for the transverse response of fiber-reinforced polymer composites
AU - Liu, Y.
AU - van der Meer, F.P.
AU - Sluys, L.J.
AU - Fan, J. T.
N1 - Accepted author manuscript
PY - 2020
Y1 - 2020
N2 - With a classical notched configuration, the damage process in the transverse plane of fiber-reinforced polymer composites are studied by a direct numerical simulation model (DNS). However, to avoid high computational costs the region in which the fiber/matrix microstructure is explicitly modeled must remain small. Therefore, away from the notch tip, a homogenized model is needed to capture the far-field mechanical response without damage but with possibly rate-dependent nonlinearity. In this contribution, with a representative volume element (RVE), a step-by-step numerical homogenization procedure is introduced to calibrate a homogenized viscoelastic-viscoplastic (VE-VP) model with the same formulation as the VE-VP model used for describing the polymer behavior in the RVE model. The calibrated VE-VP model is used in a homogenized FEM model to describe the composite material response and compared against the RVE model. It is found that: (1) the homogenized model captures the viscoelastic deformation, the rate-dependent yielding, stress relaxation and unloading behavior of the polymer composite well, although the assumptions of a single plastic Poisson's ratio and pure isotropic hardening are oversimplifications of the composite behavior; (2) the novel step-by-step numerical homogenization procedure provides an efficient and accurate way for obtaining material parameters of a VE-VP model.
AB - With a classical notched configuration, the damage process in the transverse plane of fiber-reinforced polymer composites are studied by a direct numerical simulation model (DNS). However, to avoid high computational costs the region in which the fiber/matrix microstructure is explicitly modeled must remain small. Therefore, away from the notch tip, a homogenized model is needed to capture the far-field mechanical response without damage but with possibly rate-dependent nonlinearity. In this contribution, with a representative volume element (RVE), a step-by-step numerical homogenization procedure is introduced to calibrate a homogenized viscoelastic-viscoplastic (VE-VP) model with the same formulation as the VE-VP model used for describing the polymer behavior in the RVE model. The calibrated VE-VP model is used in a homogenized FEM model to describe the composite material response and compared against the RVE model. It is found that: (1) the homogenized model captures the viscoelastic deformation, the rate-dependent yielding, stress relaxation and unloading behavior of the polymer composite well, although the assumptions of a single plastic Poisson's ratio and pure isotropic hardening are oversimplifications of the composite behavior; (2) the novel step-by-step numerical homogenization procedure provides an efficient and accurate way for obtaining material parameters of a VE-VP model.
KW - Composites
KW - Numerical homogenization
KW - RVE
KW - Viscoelasticity
KW - Viscoplasticity
UR - http://www.scopus.com/inward/record.url?scp=85088916414&partnerID=8YFLogxK
U2 - 10.1016/j.compstruct.2020.112690
DO - 10.1016/j.compstruct.2020.112690
M3 - Article
AN - SCOPUS:85088916414
SN - 0263-8223
VL - 252
JO - Composite Structures
JF - Composite Structures
M1 - 112690
ER -