Sensitivity Study for Vibrational Parameters Used in Damage Detection

Abstract

A number of researchers have proposed using vibrational behavior to monitor structures. When significant damage occurs, there are changes in the structural stiffness. This causes changes in the vibrational information. The basic vibrational information normally collected in field monitoring are the natural frequencies and mode shapes. These can be further processed to modal flexibilities. This paper presents a sensitivity study comparing use of natural frequencies, mode shapes, and modal flexibilities for monitoring. The results demonstrate that modal flexibilities are more likely to indicate damage than either natural frequencies or mode shapes.