Talks and Poster Presentations (with Proceedings-Entry):

M. Kwapisz, M. Ralbovsky, S. Lachinger:
"Uncertainty of vibration properties of a concrete highway bridge in long-term monitoring";
Talk: ISMA/USD2016, Belgien; 09-19-2016 - 09-21-2016; in: "ISMA2016", (2016), Paper ID 279, 12 pages.



English abstract:
This paper proposes method of uncertainty quantification of modal parameters and presents results
acquired from monitoring of a 10-span highway bridge in Austria. Motivation for this research was to
ensure robustness of damage detection based on long-term monitoring data. Therefore, the variability due
to changing environmental and operating conditions was of primary concern. The proposed evaluation
method uses clustering of modal identification results obtained at different conditions. Stochastic subspace
identification (SSI) was used to identify modal parameters from ambient measurements. Besides the
variability due to changing conditions, the accuracy of parameter extraction (within one data block) was
also considered. The procedure contains 3 steps of data reduction: extraction of a set of modal parameters
from one data block, statistical properties of this set, and statistical properties all sets from all data blocks.
Compensation of temperature effects was performed by regression analysis. While the temperature
influence on eigenfrequencies was significant, the mode shape and damping values showed lower but
detectable sensitivity.
Results of this uncertainty quantification are intended for the use in probabilistic damage detection.

Created from the Publication Database of the AIT Austrian Institute of Technology.