Energy Damage Detection Strategy Based on Strain Responses for Long-Span Bridge Structures

Abstract

An energy damage detection strategy through disposing strain responses has been developed. First, the strain-based energy dynamic indexes for a system with multiple degrees of freedom were derived from the frequency response function (FRF) of strain responses and energy spectra density. Then, the traditional mode-shape curvature strategy and the proposed strain-based energy damage detection strategy were both used to analyze a long-span cable-stayed bridge, and it was found through comparison that the proposed strain-based energy damage detection strategy solved the shortcomings of the traditional mode-shape curvature strategy. Finally, damage location, damage quantification, and noise pollution resistance analysis for a long-span cable-stayed bridge with different degrees of damage were carried out to verify the effectiveness of the proposed strain-based energy damage detection strategy. The numerical analysis showed that the proposed strain-based energy damage detection strategy can locate damage positions accurately, and it also has good damage quantification and noise pollution resistance abilities.