Vibration Analysis of a Cracked Beam on an Elastic Foundation

Batihan A. C., KADIOĞLU F. S.

INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS, vol.16, no.5, 2016 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 16 Issue: 5
  • Publication Date: 2016
  • Doi Number: 10.1142/s0219455415500066
  • Journal Name: INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Transverse vibration, Euler-Bernoulli beam, timoshenko beam, elastic foundation, edge crack, TIMOSHENKO BEAMS, NATURAL FREQUENCIES, ARBITRARY NUMBER, STABILITY
  • Middle East Technical University Affiliated: Yes

Abstract

The transverse vibrations of cracked beams with rectangular cross sections resting on Pasternak and generalized elastic foundations are considered. Both the Euler-Bernoulli (EB) and Timoshenko beam (TB) theories are used. The open edge crack is represented as a rotational spring whose compliance is obtained by the fracture mechanics. By applying the compatibility conditions between the beam segments at the crack location and the boundary conditions, the characteristic equations are derived, from which the nondimensional natural frequencies are solved as the roots. Sample numerical results showing the effects of crack depth, crack location, foundation type and foundation parameters on the natural frequencies of the beam are presented. It is observed that the existence of crack reduces the natural frequencies, whereas the elasticity of the foundation increases the stiffness of the system and thus the natural frequencies. It is also observed that the type of elastic foundation has a significant effect on the natural frequencies of the cracked beam.