Experimental assessment of high-rate GPS receivers for deformation monitoring of bridge

The bridge engineer has long needed methods of accurate global displacement measurement for use in construction and more recently in the areas of bridge health monitoring. In this paper, the reliability and practicability of using high-rate carrier phase global positioning system (GPS) receivers are investigated to characterize dynamic oscillations of bridges. Initially, the short baseline trial is conducted to study the precision and characteristics of such kind of receivers as well as the potential applications of such a high-frequency data rate. After that, the performance of high-rate GPS receivers for dynamic response tracking is validated against accelerometers through controlled experimental tests and a novel kind of wavelet packet-based filtering method is also proposed. Finally, on-site dynamic experiments are carried out to measure the bridge deck oscillation induced by different external loads. Observed data are compared with predicted values derived from modeling undertaken with the finite element (FE) analysis software. The results of all the experiments proved to be very encouraging, and showed that high-rate GPS receiver is successful in quantifying both environmental induced bridge vibrations and high-frequency transient motion caused by vehicle loading, providing the ability for verification and/or improvement of structural design and modeling.

► The static trial was conducted to study the background noise of the GPS receiver.
► The performance of high-rate GPS receiver for dynamic response tracking is validated.
► A wavelet packet based filtering scheme is proposed.
► On-site experiments are carried out to study the characteristics of the GPS receiver.
► Observed data are compared with predicted values derived from FE method.