The efficiency of high-rate RTK for structural health monitoring

Abstract

The purpose of Structural Health Monitoring (SHM) is to monitor the conditions of important structures, to determine natural behaviors, and to take necessary precautions in advance by determining the possible accidents. In recent years, Global Navigation Satellite Systems (GNSS) are widely used because of their high accuracy and ease of use in SHM applications. The purpose of this study is to show that high-rate RTK GNSS measurement methods can detect the behavior of engineering structures with high accuracy and to investigate that they can be used effectively in SHM. Experiments were carried out with a single-axis shake table to determine the performance of the RTK GNSS method in SHM studies. The shake table was moved harmonically to simulate possible structural movements and it is aimed to determine these movements with the 20 Hz multi-GNSS equipment. The obtained data were analyzed 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. As a result of experiments, it was determined that the high-rate RTK GNSS method can be used in observing the behavior and natural frequencies of engineering structures with a precision of a few mm.