The full-scale dynamic characteristics and fine-scale local damage of steel box girder are connected by the substructuring method to realize structural multi-scale damage analysis for a super-long-span cable-stayed bridge

Sutong Cable-stayed Bridge.The modal curvature index and modal strain energy index for damage localization of steel box girder are further comparatively studied.The analysis results show that:（i） the effect of the simulated damage in various components of the steel box girder on the dynamic characteristics of a super-longspan cable-stayed bridge should be properly considered in the structural damage analyses using the multi-scale numerical computation;（ii） in the absence of noise

modal curvature index can properly identify all structural damage cases of steel box girder

whereas modal strain energy index fails to identify some damage cases;（iii） modal strain energy index is the best in anti-noise compared with modal curvature index on the whole.