TOWARD THE IMPLEMENTATION OF ON-LINE STRUCTURAL MONITORING USING RTK-GPS AND ANALYSIS OF RESULTS USING THE WAVELET TRANSFORM

The aim of this paper is twofold. First, it describes a pilot project in Singapore, in which an RTKGPS system has been installed for the purpose of monitoring the behaviour of a high rise building. This system will contribute to a project of monitoring that commenced in 1995 with the installation of two pairs of accelerometers and two UVW anemometers. The aim of this project is to capture the building loading and dynamic response during strong winds and remote earthquakes to aid local design code development. The GPS monitoring system installed on the Republic Plaza building (at 280m, the maximum height of any Singaporean building) generates on-line antenna coordinate measurements. These will complement and corroborate the acceleration data to provide the complete picture of the building displacement across the full spectrum of loading frequencies, allowing for direct estimation of lateral loads. The system design and installation is described. The second objective of this paper is to describe a wavelet analysis procedure that has been proposed for the extraction of both the high and low frequencies of the structural dynamics from the 'raw' RTK-GPS results. The results of tests of this time series analysis procedure will be presented.