Shear contribution on viscoelastic behavior of beams modeled using plane frame elements with Reissner kinematics

The development of a numerical formulation is presented to describe viscoelastic behavior considering shear effects. The nonlinear positional formulation of the Finite Element Method is used considering plane frame elements with Reissner kinematics. The description of the viscoelastic behavior is considered through the adoption of a stress-strain relation based on Boltzmann rheological model. The used kinematics allows to describe the decoupling between the rotations and the displacements in element cross-sections. This approach allows to evaluate the contribution of shear effects in viscoelastic behavior in an original way. Based on the developments and the results obtained, it is possible to observe that strains and displacements due to viscoelastic behavior are significantly superior to the results obtained considering Bernoulli-Euler kinematics hypothesis. It is possible to notice a better agreement between the obtained numerical results and the results in the literature. Results obtained from the developed formulation allow the assessment of the shear effects on the viscoelastic behavior of plane frames.

Automated summary

A numerical formulation is presented to describe viscoelastic behavior considering shear effects. The formulation uses a nonlinear positional method and a stress-strain relation based on the Boltzmann rheological model. The results show that considering shear effects leads to significantly increased strains and displacements due to viscoelastic behavior.