8 documents found, page 1 of 1
Continuous dynamic monitoring of a prestressed concrete bridge based on strain,...
Álvaro Cunha; Wei-Hua Hu; Samir Said; Rolf G. Rohrmann; Jun TengThe Westend Bridge is located on the A100 Highway in Berlin. An integrated continuous dynamic monitoring system, composed of 20 velocity sensors, 5 temperature sensors, 3 strain gauges, 2 inclination sensors and 1 crack sensor was implemented by the Federal Institute for Materials Research and Testing (BAM) in 2000. The system runs continuously with occasional intermittence and leads to a huge amount of data ov...
Structural health monitoring of a stress-ribbon footbridge
Wei-Hua Hu; Elsa Caetano; Álvaro CunhaThis work describes the development and implementation of a structural health monitoring system on astress-ribbon footbridge. In a first part, it characterises the implemented continuous dynamic monitoringsystem and the application of automated operational modal analysis to analyse the variation of modalproperties estimates along several years. A correlation analysis is then conducted showing that environmental...
Continuous dynamic monitoring of a lively footbridge for serviceability assessm...
Wei-Hua Hu; Carlos Moutinho; Elsa Caetano; Filipe Magalhães; Álvaro CunhaThis paper aims at analyzing the feasibility of applying a vibration based damage detection approach, based on Principal Components Analysis (PCA), to eliminate environmental effects using the large amount of high quality data continuously collected by the dynamic monitoring system of Pedro e Ines footbridge since 2007. Few works describe real data, regularly collected along several years by reliable continuous...
LabVIEW toolkits for output-only modal identification and long-term dynamic str...
Wei-Hua Hu; Álvaro Cunha; Elsa Caetano; Filipe Magalhães; Carlos MoutinhoThis paper describes the development of computational tools for modal identification and long term dynamic monitoring in LabVIEW environment. These tools mainly consist of two individual toolkits for structural modal identification (SMI) and continuous monitoring (CSMI), respectively. The SMI toolkit implements the frequency domain Peak-Picking (PP) and Enhanced Frequency Domain Decomposition (EFDD) method, as ...
Temperature effects on modal variability of a stress-ribbon footbridge under op...
Wei-Hua Hu; A. Cardoso; F. Magalhães; E. Caetano; A. CunhaThis paper reports the environmental effects on modal properties of the stress-ribbon footbridge of FEUP Campus, based on experimental data acquired by a continuous dynamic monitoring system, with remote control through the Internet, working permanently since June 2009, which comprehends a set of piezoelectric accelerometers and temperature sensors. A toolkit in LabVIEW environment was developed to process all ...
Analysis and extraction of temperature effects on natural frequencies of a foot...
Wei-Hua Hu; Carlos Moutinho; Filipe Magalhães; Elsa Caetano; Álvaro CunhaThe development of efficient vibration based structural health monitoring systems requires distinguishing between abnormal changes in modal parameters caused by structural damage and normal changes due to varying environmental conditions. In this context, this paper is focused on the analysis and extraction of effects of temperature oscillations on natural frequencies of a footbridge, where a long-term dynamic ...
Implementation of a dynamic monitoring system at coimbra footbridge
Carlos Moutinho; Wei-Hua Hu; Elsa Caetano; Álvaro CunhaCoimbra footbridge is a new structure that connects both banks of Mondego River. Preliminary studies conducted during design stage indicated some vulnerability to vibrations induced by pedestrians, both for lateral and vertical directions. As result, it was decided to install Tuned Mass Dampers in 5 different sections of the deck, as well as a dynamic monitoring system to evaluate the vibration levels observed ...
A signal processing, result management and visualization system for evaluation ...
Wei-Hua Hu; Carlos Moutinho; Álvaro Cunha; Elsa CoutinhoThis paper describes a system developed in LabVIEW environment to monitor the long term dynamic behavior of bridges. This system comprises three main parts: an automated signal processing toolkit, including automated vibration level detection and system identification; a database to organize the results, in text and graph format, generated from the signal processing toolkit; and a user-friendly results visualiz...