FBG sensing system to study the bridge weigh-in-motion for measuring the vehicle parameters

In this paper, an FBG based Weigh-in-Motion (WIM) sensing system is designed by using two FBGs, each one attached at the central span portion of the girder between two piers of a bridge model. The FBG's are pasted at an inclination of 45
^o
. Experiments were conducted to study the response of the designed WIM system varying the loads and velocity of the vehicle. The temporal response of the FBG's and shift in the wavelength is recorded using interrogator of resolution 1pm. The response of the sensor system for velocity and load showed a linear variation with a good correlation up to 150m/sec velocity and 5N weight respectively. The results reveal that the proposed system is capable of monitoring the dynamic response due to the changes in the load and velocity of the moving vehicle over the bridge.