%0 Journal Article
%T Bridge Assessment and Health Monitoring with Distributed Long-Gauge FBG Sensors
%A Chunfeng Wan
%A Wan Hong
%A Jianxun Liu
%A Zhishen Wu
%A Zhaodong Xu
%A Shu Li
%J International Journal of Distributed Sensor Networks
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/494260
%X Most sensors for structural testing and health monitoring are ˇ°pointˇ± sensors which strongly limit the ability to correct damage detection and structural assessment. In this paper, long-gauge FBG sensor which can sense the whole area within the gauge length is introduced. Bridge assessment and health monitoring with the microstrain distribution acquired by the distributed long-gauge FBG sensor are also studied. Experiments were conducted and application to a real prestressed box bridge was also implemented. Static and dynamic testing results show that distributed long-gage FBG sensing technique can obtain not only the global information such as bridge deflection and natural frequency, but also the local parameters such as strain and modal macrostrain to detect damage of the bridge. It shows that structural assessment and health monitoring based on the proposed technique have great potential in maintenance of civil engineering infrastructures. 1. Introduction Bridges are the most important facilities for many cities and countries. These infrastructures provide the necessary communication and transportation conditions for the residence. However, progressive deterioration of the civil infrastructure begins once they are built and subjected to normal continuous and occasional excessive loading, or adverse environmental conditions. For the purpose of protecting and maintaining these infrastructures, prompt and intensive monitoring of structural system becomes extremely important. Nowadays, most Structural Health Monitoring (SHM) research has focused either on global damage assessment techniques using structural dynamic responses or on limited local independent damage detection mechanisms. Vibration-based global SHM using typical acceleration measurements still faces some challenges for the reason that structural modal parameters seem too ˇ°globalˇ± to detect the damage that is an intrinsically local phenomenon in structures. On the other hand, although relatively reliable, local inspections are cost, labor-intensive, and too ˇ°localˇ± to obtain the integrated information for the overall structure. Under this background, the concept of distributed long-gage FBG sensing techniques, which is dedicated to catching and utilizing the strain distribution throughout the full or some partial areas of structures to detect damage, has been proposed to develop an integrated SHM strategy [1]. As a typical local measurement, strain has been verified to be very sensitive to damage. However, for the health monitoring of large-scale civil structures, strain measurement always
%U http://www.hindawi.com/journals/ijdsn/2013/494260/