A NATURAL FREQUENCY-BASED TECHNIQUE TO DETECT STRUCTURAL CHANGES
Dr. Suresh K, Sharanappa Sajjan
Department of Mechanical Engineering,
Government Engineering College, Talakal, Koppal-583238, India
Abstract: Structural changes within materials often indicate potential damage caused by design flaws, fabrication errors, overloading, natural events, or aging. Cracks, a common type of defect resulting from fatigue or mechanical stress, can propagate under cyclic loading and lead to structural failure if undetected. Monitoring natural frequency variations provides a reliable, non-destructive method for detecting such defects. This study investigates the influence of crack size on the natural frequencies of a cantilever beam using analytical, numerical, and experimental approaches. Analytical modeling is based on Euler–Bernoulli beam theory, numerical simulations are carried out in COMSOL Multiphysics, and experimental validation is performed using a copper cantilever beam subjected to both free and forced vibration tests. Results show that increasing crack size reduces the natural frequency due to local stiffness degradation. The close agreement among analytical, simulation, and experimental findings demonstrates the effectiveness of frequency-based monitoring as a practical tool for structural health assessment.
Keywords: Vibration, Condition Monitoring, Structural Health, Crack Detection, Natural Frequency, Cantilever Beam
VOLUME 9 ISSUE 11 2025: 49- 59