Wavelet-based analysis technique for the monitoring of tall structure under normal loading using GPS

With the development of GPS receiver technology for high recording rate, it allows reliable monitoring of engineering structures, such as suspension bridges, towers and tall buildings. The distinctive advantage is that relative displacements can be measured to access the stress and drift of engineering structures, but accuracy of GPS positioning is affected by many error sources or biases, e.g. satellite and receiver related clock error, orbital errors, atmospheric delay, and multi-path. The relatively smaller amplitude of structure vibration may usually be hidden from view. The paper presents a wavelet-based analysis technique for this application and results from field experiment data acquired at a tall building (309.95m from ground level) shows that small amplitude of 1 - 2mm at normal loading condition can effectively be identified.