Nonlinear dynamics and chaos in a pseudoelastic two-bar truss

Abstract

Stability aspects of structures are usually treated by archetypal models that provide globalcomprehension of the system behavior. The two-bar truss is an example of this kind ofmodel that presents snap-through behavior. This paper deals with the dynamical responseof a pseudoelastic two-bar truss, representing an archetypal model of a structural systemthat exhibits both geometrical and constitutive nonlinearities. Adaptive trusses with shapememory alloy actuators are examples of dynamical systems that may behave like thestructure considered in this paper. A constitutive model is employed in order to describethe SMA behavior, presenting close agreement with experimental data. An iterativenumerical procedure based on the operator split technique, the orthogonal projectionalgorithm and the classical fourth order Runge–Kutta method is developed to deal withnonlinearities in the formulation. Numerical investigation is carried out consideringfree and forced responses of the pseudoelastic two-bar truss showing complexbehaviors.