Online damage diagnosis for civil infrastructure employing a flexibility-basedapproach

Abstract

Structural health monitoring (SHM) and damage detection have recently emerged as a newresearch area in civil engineering. Continuous and long-term monitoring of civilinfrastructure is desirable, because it allows the damage in the structure to be detected atan early stage so that necessary measures can be carried out to prolong and optimizethe associated service life and cost. In this paper, an approach which extends aflexibility-based damage detection technique, the damage locating vector (DLV)method, for continuous online SHM is presented. The essence of the proposedapproach is to construct an approximate flexibility matrix for the damaged structureutilizing the modal normalization constants from the undamaged structure. Thisextended DLV method can then be applied for online damage diagnosis. Numericalsimulation has been conducted using a 14-bay planar truss structure, with the resultsshowing that the proposed approach works well for both single- and multiple-damagescenarios.