MODAL ANALYSIS OF A CONCRETE HIGHWAY BRIDGE - STRUCTURAL CALCULATIONS AND VIBRATION-BASED RESULTS.pdfVIP

The 6th International Conference on Structural Health Monitoring of Intelligent Infrastructure Hong Kong | 9-11 December 2013 MODAL ANALYSIS OF A CONCRETE HIGHWAY BRIDGE - STRUCTURAL CALCULATIONS AND VIBRATION-BASED RESULTS Shengfa Miao 1,3 , René Veerman 2 , Eddy Koenders 2,4 and Arno Knobbe 1 1. Leiden Institute of Advanced Computer Science (LIACS) Leiden University, Leiden, the Netherlands 2. Faculty of Civil Engineering and Geosciences Delft University of Technology, Delft, the Netherlands 3. School of Information and Engineering Lanzhou University, Lanzhou, China 4. COPPE - Programa de Engenharia Civil Federal University of Rio de Janeiro, Brazil ABSTRACT In the field of civil infrastructure, Structural Health Monitoring systems are implemented more and more frequently with the aim to safeguard the safety and service-life of structures such as bridges and tunnels. Changes in the integrity of the material and/or structural properties of this class of structures is known to adversely affect their performance, which can also be observed from the structures’ dynamic response, such as the natural frequencies, damping ratios and mode shapes. The procedure to obtain these response parameters is known as modal analysis. Two methods for obtaining these parameters are compared in this paper, one based on a careful analysis of measured vibration sensor data, and another one is based on a structural calculation using a Finite Element Method (FEM). The dynamic modal characteristics of a structure can be obtained by using vibration-based damage identification techniques such as Stochastic Subspace Identification (SSI). The SSI technique is capable of extracting modal parameters from output-only measurements, i.e. using raw data collected by simply monitoring a structure under its normal load. In this paper the application of SSI for the “Hollandse Brug”, which is a six-lane Dutch