Nonlinear Vibrations of a Beam with a Breathing Edge Crack Using Multiple Trial Functions


Batihan A. C. , CİĞEROĞLU E.

34th IMAC Conference and Exposition on Structural Dynamics, Florida, United States Of America, 25 - 28 January 2016, pp.1-9 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1007/978-3-319-29739-2_1
  • City: Florida
  • Country: United States Of America
  • Page Numbers: pp.1-9
  • Keywords: Breathing crack, Euler-Bernoulli beam, Galerkin's method, Harmonic balance method, Nonlinear vibrations

Abstract

In this paper, a beam like structure with a single edge crack is modeled and analyzed in order to study the nonlinear effects of breathing crack on transverse vibrations of a beam. In literature, edge cracks are generally modeled as open cracks, in which the beam is separated into two pieces at the crack location and these pieces are connected to each other with a rotational spring to represent the effect of crack. The open edge crack model is a widely used assumption; however, it does not consider the nonlinear behavior due to opening and closing of the crack region. In this paper, partial differential equation of motion obtained by Euler-Bernoulli beam theory is converted into nonlinear ordinary differential equations by using Galerkin's method with multiple trial functions. The nonlinear behavior of the crack region is represented as a bilinear stiffness matrix. The nonlinear ordinary differential equations are converted into a set of nonlinear algebraic equations by using harmonic balance method (HBM) with multi harmonics. Under the action of a harmonic forcing, the effect of crack parameters on the vibrational behavior of the cracked beam is studied.