Damage evaluation in high-rise buildings using one modal eigenpair

Abstract

A development of the ‘first-order storey pseudo-stiffness-based damage index’ of high-rise buildings is presented in this article. The proposed damage index is based on identification of an input set of one modal eigenpair, consisting of one modal frequency and the corresponding mode shape, overcoming the need and the difficulties of identifying multiple sets of eigenpairs in operational modal analyses of multistorey buildings. The calculation of first-order storey pseudo-stiffness-based damage index is expressed as a simple numerical procedure for comparison between the dynamic parameters of undamaged and damaged structures. The accuracy of the proposed damage assessment approach has been verified in two different tests – numerical and experimental. The numerical tests are based on the calculation of first-order storey pseudo-stiffness-based damage index in numerical models in which the structural damage is simulated with previously defined storey stiffness degradation. The experimental test consists of first-order storey pseudo-stiffness-based damage index accuracy test on the structure of the Urban Disaster Prevention Research Center, located in Tsukuba, Japan, and comparison to the results obtained by previously proven accurate damage detection method. The test results have shown that the proposed first-order storey pseudo-stiffness-based damage index index, based on the first modal eigenpair, can be applied as an instant damage detection method in structural health monitoring of multistorey buildings, providing the location and severity of structural damage.