Simulation of the column bending test using an anisotropic viscoelastic shell model

Finite element simulation of the column bending test (CBT) is carried out using shell elements with anisotropic viscoelastic section properties. The CBT is an experimental method for evaluating the bending behavior of thin-ply high strain composites (TP-HSC), to support development of deployable composite booms for space structures. A linear viscoelastic shell formulation is derived and implemented using two solution techniques: quasi-elastic (QE) and direct integration (DI). The model inputs, namely Prony series of the ABD matrix, are obtained using Mechanics of Structure Genome. The model is implemented in Abaqus as a UGENS user-subroutine. Recent CBT experiments are briefly reviewed, and a shell element model is developed including the geometrically nonlinear features of the test. Comparisons of the test and analysis results show that the model is capable of predicting most of the measured trends. Nonuniform deformation is captured and emphasized in data reduction considerations. Although relaxation can be captured with QE implementation of the viscoelastic model, to capture the residual curvature DI implementation is necessary. Residual curvature measured in the tests, but not predicted by the present model, suggests that viscoplasticity should be considered. A demonstrative study also shows the potential of material model calibration using the virtual CBT developed in this work.