Equivalent continuum modeling of beam-like truss structures with flexible joints

Abstract

The paper investigated the equivalent continuum modeling of beam-like repetitive truss structures considering the flexibility of joints, which models the contact between the truss member and joint by spring-damper with six directional stiffnesses and dampings. Firstly, a two-node hybrid joint-beam element was derived for modeling the truss member with flexible end joints, and a condensed model for the repeating element with flexible joints was obtained. Then, the energy equivalence method was adopted to equivalently model the truss structure with flexible joints and material damping as a spatial viscoelastic anisotropic beam model. Afterwards, the equations of motion for the equivalent beam model were derived and solved analytically in the frequency domain. In the numerical studies, the correctness of the presented method was verified by comparisons of the natural frequencies and frequency responses evaluated by the equivalent beam model with the results of the finite element method model.