As part of the thesis, we tested a system for permanent vibration measurements installed on the building of the Faculty of Civil and Geodetic Engineering, University of Ljubljana. In the first phase, we tested various accelerometers. Accelerometers are devices for detecting environmental vibrations in terms of accelerations and are suitable for use in determining the dynamic properties of structures. We describe and use three sensors: Dewesoft IOLITEiw 3xMEMS-ACC and IOLITEiw 3xMEMS-ACC-S, and the Kinemetrics EpiSensor Model FBA ES-T. Based on the understanding of the basic characteristics of the sensors, testing was performed on a shake table under various sinusoidal and seismic motion cases. The measurement results from different sensors at different sampling frequencies and for different excitation cases were compared by plotting acceleration spectra and Fourier spectra. In the second phase, we tested the system for permanent vibration measurements based on ambient and forced vibrations aimed at determining the vibration period of the Faculty of Civil and Geodetic Engineering building in the transverse and longitudinal directions. We found that the sensors IOLITEiw 3xMEMS-ACC-S and Kinemetrics EpiSensor Model FBA ES-T provided similar results for the building's vibration period. In the building's transverse direction, the vibration period ranged from 0.55 seconds to 0.58 seconds, and in the longitudinal direction, from 0.41 to 0.43 seconds, depending on the sensor used and the measurement of ambient or forced vibrations. Using the Dewesoft IOLITEiw 3xMEMS-ACC sensor, we were not able to distinctly determine the building's natural frequency due to the low intensity of vibrations.
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