Modal Analysis of Structural Vibration

Abstract

Modal analysis is a powerful tool to identify the dynamic characteristics of structures. Every structure vibrates with high amplitude of vibration at its resonant frequency. It is imperative to know the modal parameters — resonant frequency, mode shape and damping characteristics of the structure at its varying operating conditions for improving its strength and reliability at the design stage. The paper elucidates the behavior of a two storey metallic structure modeled to understand its dynamic characteristics of structure with the help of vibration dynamic signal analyzer, accelerometer, impact hammer and post-data analysis software. Single reference testing method has been used for the experimental analysis. Frequency response functions (FRFs) have been analysed with the help of modal analysis software. The theoretical modal analysis technique has also been investigated using finite element method (FEM). The results obtained from the theoretical and experimental analysis have been compared to draw the conclusion.