Structures oscillations monitoring with global positioning system and adaptive filtering techniques: Fid-Bau Portal

Structures oscillations monitoring with global positioning system and adaptive filtering techniques

Larocca, Ana Paula C. / Ernesto Schaal, Ricardo / Simões da Fonseca, Edvaldo

–

This paper aims to detect small dynamic displacements by analysis of L1 Global Positioning System carrier frequency using an improved method for collecting data and filtering techniques on monitoring large structures. It is proposed to analyze the phase residuals directly from the raw phase observable data collected in a short baseline during a limited time span, in lieu of obtaining the residual data file from regular GPS processing programs.

Design/methodology/approach –

The approach of this paper is an update on the method based on the interferometer idea for analyzing the Global Positioning Systems signals applying adaptive filtering techniques on the phase residuals computed through the double difference adjusted by the 3rd order polynomial. The method is based on the frequency domain analysis of the phase residuals resulted from the L1 double difference static data processing of only two satellites.

Findings –

This research improves the ability to characterize the dynamic behavior of large structures though the detection of millimeter-level data of structural amplitude oscillation response and its frequency value.

Practical implications –

Support of Civil Engineers by collaboration on monitoring oscillations of spans and towers of large bridges; determination of amplitude oscillations value and low-frequency modal values. The paper presents two trials to verify the proposed methodology for using GPS as a tool for monitoring large structures.

Originality/value –

The paper presents a comprehensive framework and implementation approach to demonstrate the capabilities of Global Positioning System as a tool for monitoring large structures providing accurate response data at high levels of precision.