Damage Identification of Multistory Shear Structure from Sparse Modal Information

Abstract

This paper presents a procedure to identify the damage of multistory shear structure from sparse modal information. Practically, it is difficult and expensive to measure modal response at many locations. A method has been proposed to compute the full modal information of a particular mode simply by knowing the frequency value of that mode. Then the concept of the residual force vector along with genetic algorithm has been implemented to get the location and extent of damage. Frequencies at different number of modes with and without corresponding partial mode shape is used as input to the model and results are compared to find out minimum number of modal information and their locations required for the best result. Experimental data are simulated numerically by solving eigen value problem of the damaged structure with inclusion of random noise on the vibration characteristics. Reliability of the procedure has been shown by various examples of multistory structure with different damaged situations. The model is also validated with some published results in this area to show the efficacy of the methodology.