Structural causes of temperature affected modal data of civil structures obtained by long time monitoring

摘要

The paper is presenting data from health monitoring of a highway bridge in Berlin with the main attention to temperature affected modal data. The results cover measurements from a three years continuous monitoring process. Trying to understand what are the real technical causes for the environmental influence to the variations of measured natural frequencies sued for signatures to damage detection numerical simulations are performed. A;;oying adjusted dynamic and thermic finite element models damage scenarios and thermic sensitive parameters are used helping to clarify the structural behaviour doe to thermic loading. A proposal as made for applying a functional proportionality between temperature variations and changing natural frequencies for civil structures.