Mass loading and temperature compensation for long-term ambient measurement data of a freeway bridge

摘要

This contribution addresses the compensation of disturbing effects on performance indicators in the framework of structural health monitoring of bridge structures. Basis of this study is the ambient acceleration response of a freeway bridge located in the Austrian Alps, recorded in a long-term monitoring campaign over five years. The two investigated effects are the non-stationary added mass of the traffic volume and the exposure of the bridge to seasonal ambient temperature changes. In the first part, the impact of added mass on an identified natural frequency is quantified. With trucks crossing the bridge modeled as rigid lumped mass, the mass loading effect on the performance indicator is rather small. In the second part, three different black-box input-output models for compensating the influence of the ambient temperature on the identified frequency are developed. It is shown that the developed black-box models facilitate at least partially the desired compensation of the temperature effect on the considered bridge frequency.