Fiber Grating High-speed Weighing System Development

With the rapid development of economy these years, China witnesses serious Transportation overmarging and overloading, which have become a stubborn illness in the Transportation industry. Overloaded and overmarged vehicles have seriously shortened the service life of our roads and bridges and thus caused great damage to the traffic safety and the national economy. The currently widely used Weight-in-Motion system is weak in high-speed detection and durability. A new high-speed Weight-in-Motion system with reinforced durability is really in urgent need.The thesis develops a high-speed Wight-in-Motion system with better durability and stability- FBG Weight-in-Motion system in which FBG is used as the sensor to weight the vehicle passing by dynamically with bending plate Weight-in-Motion principle. This system can detect the traffic load parameters e.g. speed, axle load, complete weight, axle base, etc. The thesis proceeds in the following way:Firstly, elaborate the basic principles of FBG and its characteristics in strain and temperature measurement, and introduce the development of FBG and its application in civil engineering.Secondly, improve the weigh-in-motion principle of bending plate by: 1) proposing that the calibration coefficient of the system is a linear function with the independent variable speed, and its constant term is a parameter synthetically affected by pavement roughness; 2) proposing a complementary formula to repair the system output for improving the weighing precision in the case of wheel load acting at the marginal zone of the weighting plate.Thirdly, design an integrated FBG Weight-in-Motion system: 1) lay out the hardware of FBG Weight-in-Motion system; 2) program the FBG Weight-in-Motion system with Labview.Fourthly, finish the static load test and compare the performance of the FBG Weight-in-Motion system with the Resistance Strain Gauge; finish the dynamic load test and compare the precision of the FBG Weight-in-Motion system with another existing Weight-in-Motion system.Fifthly, apply the FBG Weight-in-Motion system in practical engineering, by investigating the axle load of Yangang Road, Shatian town, Dongguan city in Guangdong province.