Nonlinear properties of Lamb waves under modulation of fatigue damage: Finite element simulation with experimental validation

Ming Hong, Chao Zhou, Zhongqing Su, Li Cheng, Xinlin Qing

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review

4 Citations (Scopus)

Abstract

Engineering structures under cyclic loads experience continuous accumulation of fatigue damage, deteriorating at an alarming rate. Most existing structural health monitoring (SHM) techniques use linear signal features, which may be unwieldy to the detection of fatigue damage in an initial stage. A dedicated finite element (FE) modeling technique for simulating nonlinear properties of ultrasonic Lamb waves under the modulation of fatigue cracks in metallic materials was established. Piezoelectric wafers were included in the model for exciting Lamb waves and capturing nonlinear characteristics. A nonlinearity parameter was constructed to calibrate the extracted wave nonlinear properties. Feasibility of the FE technique was experimentally validated, and the results showed satisfactory consistency in between, both revealing that (i) the developed FE modeling technique is able to faithfully simulate fatigue crack-induced nonlinear properties in Lamb waves, providing repeatable characterization for fatigue cracks; (ii) the defined nonlinear parameter decreases when the direct wave path offsets from the fatigue crack, nonlinearly subject to the offset distance from the crack to a sensing path; and (iii) a cumulative growth of the nonlinearity parameter against the wave propagation distance exists. All the observations enable quantitative characterization of micro-fatigue cracks using embeddable piezoelectric wafers, facilitating development of SHM technique with a capacity of quantitatively detecting damage small in dimension.
Original languageEnglish
Title of host publicationStructural Health Monitoring
Subtitle of host publicationResearch and Applications
Pages195-204
Number of pages10
DOIs
Publication statusPublished - 26 Jul 2013
Event4th Asia-Pacific Workshop on Structural Health Monitoring - Melbourne, VIC, Australia
Duration: 5 Dec 20127 Dec 2012

Publication series

NameKey Engineering Materials
Volume558
ISSN (Print)1013-9826

Conference

Conference4th Asia-Pacific Workshop on Structural Health Monitoring
CountryAustralia
CityMelbourne, VIC
Period5/12/127/12/12

Keywords

  • Fatigue crack characterization
  • Finite element method
  • Lamb waves
  • Nonlinear ultrasonics
  • Structural health monitoring

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Cite this