Abstract
In recent years, geodetic methods have been preferred due to their high accuracy and ease of use in the Structural Health Monitoring (SHM) Surveys. In this study, harmonic oscillation tests were carried out on a single-axis shake table to examine the usability of the Single Base and the Network RTK GNSS method in Structural Health Monitoring studies. The shake table was moved harmonically at different frequencies and amplitudes to simulate possible structural movements and it is aimed to determine these movements with the 20 Hz multi-GNSS equipment. The obtained data were evaluated by time series analysis and fast Fourier transform techniques, and the frequency and amplitude values of the movements were calculated. The accuracy of the results was determined by comparing GNSS displacements with the results obtained by LVDT (Linear Variable Differential Transformer) which is the position sensor of the shake table. So the advantages of the two RTK methods over each other were determined by comparing the amplitude and frequency differences. In addition to comparing the methods with each other, the consistency of the methods was checked by collecting data when the shake table was stationary. As a result of all experiments, it was determined that the Single Base and the Network RTK GNSS method can be used in observing the behavior and natural frequencies of engineering structures with a precision of a few mm.