Detection of anomalous sequences in crack data of a bridge monitoring

Abstract

For estimating the remaining lifetime of old prestressed concrete bridges, a monitoring of crack widths can be used. However, the time series of crack widths show a strong variation mainly caused by temperature and traffic. Additionally, sequences with extreme volatility appear where the cause is unknown. They are called anomalous sequences in the following.We present and compare four methods which aim to detect these anomalous sequences in the time series. Volatilities caused by traffic should not be detected.