Experimental verification for detection of damage of sensor-arrayed truss domes using afocusing strategy

Abstract

A damage detection scheme using a focusing strategy, developed for the purpose ofmaintaining structural integrity of truss domes during their service life, that estimates thelocation and extent of damage on the basis of vibration monitoring and systemidentification is presented. The main idea of the focusing strategy is to reduce the numberof unknown physical parameters as much as possible by shifting from global tolocal damage detection gradually. The scheme is divided into three stages: global,intermediate and local damage detection. In the global damage detection, the centralconcern is whether the damage occurs in the superstructure or substructure. Inthe intermediate damage detection, possible damaged regions are located in thesuperstructure. In the local damage detection, damaged members or joints are located inthe damaged regions. Finally, the extent of member, joint or support damageis quantified in terms of member stiffness reduction ratios. Depending on thedamage detection levels, different probing forces are used and different damageindices are defined. To verify the overall damage detection scheme, a series ofshaking table, vibration generator and impact hammer tests have been carried outfor a small-scale experimental model. On the basis of the damage identificationresults, the effectiveness and limitations of the proposed scheme are discussed.