Train overload and unbalanced load detection based on FBG gauge

This paper presents the application of the FBG sensing technology for train overload and unbalanced load monitoring. A type of FBG strain gauges is designed，which can avoid chirped FBG, and enhance sensitivity. A sensor installation method is worked out for nondestructive detecting, enabling sensors to adapt to adverse circumstance by installing FBG sensing device on steel rails, and making use of real time wavelength offset value of FBG sensors, and the dynamic detection of wheel axle load can be achieved. Comparing dynamic axle load distribution of the two tracks, the unbalanced load conditions of carriages can be obtained. The sum of axle load of a carriage turns out to be the total weight of the carriage. Meanwhile, the monitoring system possesses a function of monitoring wheel tread defect.