A New Approach to Force Estimation and System Identification in Beam-like Structures: Mode Description

Abstract

Structural health monitoring methods aim to identify the system and therefore the damage in the system during the operation of the structure, the building is exposed to ambient vibrations. The mode description method, which aims to estimate the mode variables according to the force position acting from two different degrees of freedom, uses the modal plot method in the system identification step. Modal plots are produced by a method applied in free vibration. In this study, it has been shown that a method used for system identification under free vibration can also be used for system under ambient vibrations. In ambient vibration analysis, the forces acting on the structure are not measured. However, knowledge about which points the force acting on the structure is an important piece of information for damage detection, because close to these zones, damage is more likely to occur. It has been shown that using modal plans in beam-like systems, force position estimation can be made under ambient vibrations without measuring force. For the system identification step to be performed with minimum error, the input force location must be close to the degree of freedom analyzed and the frequency of data sampling rate should be chosen according to the target frequency range. © 2022, TUBITAK. All rights reserved.