Embedded ultrasonic transmission sensors and signal processing techniques for structural change detection in the Gliwice bridge

International audienceThe present work is a part of a collaborative European funded research project named Infrastar, that aims to deal with advanced monitoring such as load, temperature and strain measurements for fatigue damage assessment in bridges and wind turbines. The main scope of this research is to develop an embedded monitoring system for durability assessment of bridges. The system must interface and integrate the original practice principally based on traditional sensors and combine the response of several diffuse ultrasonic sensors, installed on the structure to monitor the progress of changes, damage with improved realistic degradation models. The system and the embedded sensors were installed to analyze the parameters for the most important material degradation due to operational changes, corrosion of reinforcement, and alkali-silica reaction as well as to detect the abnormal structural nature: static deformation, strain, propagation of crack and transform to safety. The propagation of the several patterns of damage mechanisms can be computed by monitoring the primary environmental parameters of the material (such as thermal load, humidity for the concrete), and key operational parameters (such as strains, deflections, impulse). This paper presents recent advances in bridge structures using embedded monitoring system, which was tested on the real bridge located in Gliwice (Poland). The approach was based on using multiple embedded sensors of different types and based on the obtained measurement signals. The further signal processing was performed using the features of the acquired signals. The applied approach allowed to precisely observe various loading scenarios, which proves its superiority in structural health monitoring. Moreover, the applied sensor network reveals its durability and high measurement precision, which additionally proves the possibility of long-term monitoring of concrete structures