Time domain method for bridge structural damage alarming when a train is running

Based on the correlation between bridge's damage state and train load when a train was running on a railroad bridge,a time domain method for bridge structural damage alarming was presented.Firstly,the structural damage sensitivity was analyzed to find out the vulnerable sections in the bridge.Then,the appropriate subdomains were selected from the time domain when the train was running on the railroad bridge,according to the damage state of the vulnerable sections.At last,by using the acceleration time domain data as the damage index,a support vector machine which was one of pattern recognition methods was used for damage alarming in each subdomain.A continuous girder was analyzed, and the results showed that this method has a preferable capability of identification and noise resistance.