Identification of Multiple Cracks on Beam using Fuzzy Logic

Abstract

Presence of damage in material will affect the structural behavior and this effect can be identified by vibration parameters such as frequency, mode shape and damping. Identification of damage using vibration parameters is gaining its importance in scientific and engineering community. In few cases, change in frequencies and mode shapes are very small, especially when the damage is very minor. In such cases it is very difficult to identify by using basic comparison methods. And identifying minor damages at the initiation stage of will stop the further propagation and also increase the service life of the structure. This study demonstrates the identification of multiple damages (4 cracks) on steel cantilever beam with help of vibration parameters. These parameters particularly have first three natural frequencies and are calculated by numerical approach (ANSYS 18.1) for all possible damage cases (Forward method) and train the fuzzy logic to predict location and severity of the damage (Invers method).